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ENGLISH EDITION Magazine num. 8 Nurstech – December 2009
Research Leaf Diagnosis
Olives and Olive OilHigh Yield, Low Cost and Best Oil Quality
CultivationSuper High Desity Olives – Mechanical Harvesting
Orchard ManagementSalinity in Olive Groves
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Editorial, page 3A Refuge in Time of Crisis
Orchard Management, page 4Salinity In Olive Orchards
Orchard Management, page 9Productive Development
Research, page 15Leaf DiagnosisA Method of Monitoring Proper Nutrition in Olive Plantations
Olives and Olive Oil, page 23High Yield, Low Cost and Best Oil QualityWhat can it do for you
Cultivation, page 27Super High Density OlivesMechanical Harvesting
Cultivation, page 32Water Management For Oil Olives
News, page 35 NursTech Mini-Camp AttendeesA Grower’s Trip to ChileNursTech Announces New Distributors
The views expressed in this issue are those of the authors and are not necessarilly the opinion of Olint Magazine or NursTech, Inc.
High density olive orchards magazineEditor/Art Direction: Jeffers Richardson
E-mail: [email protected]://www.olint.com
Edition:
NURSTECH
612 East Gridley RoadGridley, California 95948 (USA)
Phone: 530 846 0404Fax: 530 846 2549
http://www.nurstech.com
Cover photo: Courtesy of Brady Whitlow of Corto Olive Oil, Lodi, CA
Summary
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EDITOrIaL
For the past year, we have heard the word “crisis” bantered around in the press, in reference to the financial crisis, the housing slump, job losses, etc.
Evidently, the glory days of huge sums of money moving from one sector to the other are over. The agriculture sec-tor, however, appears to have weathered the storm better. For better or for worse, agriculture is not a place where one becomes rich over night, but neither is it a place that suffers the huge downturns that other sectors do. True, we have our issues regarding the use of water, but the land’s value remains the same or increases only slightly, and the crops value, remains relatively consistent as well. Fortunately, the super high-density (SHD) sector has been growing rapidly throughout this past year’s economic crisis. Are the olive orchards a place to take refuge from these stormy times? Are current cultivation techniques truly worth their value? Given SHD’s efficient use of the land and water, its proven record of a good return to the grower, as well as an increas-ing demand for quality extra virgin olive oil, we believe that the answer is “yes” to both these questions. Super
a refuge in Time of Crisishigh-density olive orchards offer a sound and economic alternative to an economic downturn that has affected other sectors.
That is why, in this edition, we offer reliable information on the cultivation of SHD olive trees, the harvesting of olives, and the production of high quality olive oil. For example, we explore the possibilities of foliar diagnoses as a guide to olive fertilization, ways to deal with salinity in olive groves, and water management in the orchard for maximizing yields and oil quality. Without taking our eyes off the steps we must take in the field for maximum yield and quality, we dive into efficiencies at the mill as well as some improve-ments to olive harvesting equipment. Also, in this edition, we go out into the field to observe in detail the different states of the olive from the bud to its full development. Because of its efficiency, production of high quality extra virgin olive oil, good return on investment and increasing consumer demand, we believe the SHD olive sector can be a refuge during these stormy times.
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SOIL EC ds/m0 2.7 3.8 5.5 8.8 14
120
100
80
60
40
20
0
% p
rodu
ctio
n
Salinity in Olive GrovesOrCHarD maNaGEmENT
Xavier rius Agronomist. Director of Agromillora Iberia, S.L.
S alinity is a serious problem that concerns olive grow-ers in many countries, so knowing its implications and proper management are of vital importance to
the future of affected plantations. Inadequate irrigation can worsen salinity problems, causing higher local water tables, bringing salts to the surface, concentrating them through evaporation and also leading to higher saline content in rivers.
Olive trees’ capacity to tolerate salinity levels without harvest-ing losses depends on the salinity of irrigation water, soil drainage characteristics, local rainfall levels to wash away salts, and the soil’s current salinity.
ThE EffECTS Of SALINITy ON AN OLIvE GROvESaline soils (CE > 2 dS/m, PIS < 7) are those whose salt content leads to increased osmotic pressure of the soil
Trees with high levels of defoliation due to salinity
solution and prevent much of the water in the soil from being absorbed by the trees. Saline soils do not degrade the soil’s physical properties; their main consequence is a reduction in plant growth (or plant death) due to a lack of water. EC: Electric conductivity of soil when saturated. PIS: percentage of interchangeable sodium.
The roots, which act as a semi permeable membrane, need to make a greater effort (the more saline the soil, the greater the effort) to overcome the tendency of the water to leave the xylem in order to equalize the osmotic pressure against the water in the exterior. The symptoms of salinity are therefore similar to those of drought.
The symptoms of chloride and sodium toxicity begin with a yellowing of the edges of leaves which extends towards the center as stress increases, eventually killing the leaves.
fIGuRE 1. RATIO bETwEEN % PRODuCTION AND SOIL EC (SATuRATED PASTE)
MASS & hOffMAN, 1977
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Salinity is expressed as electric conductivity (deciSiemens per meter: dS/m) in an extract of paste-saturated soil. A dS/m is the equivalent of an osmotic pressure of 36 kPa. (See Figure 1.)
In most irrigated plantations, irrigation water is the main source of salts in the root area. An olive grower annually applying a total irrigation of 2 Ml/ha with a moderate irrigation-water saline level of 0.60 dS/m will be adding about 0.7 tons of salts per hectare/year.
Irrigation-waterSalinty: dS/M
Annual Volume of Irrigation: Ml/ha
0.3
0.6
1.5
1.9
1
0.3
0.6
1.5
1.9
2
0.6
1.3
1.9
3.8
4
1.3
2.5
3.8
7.7
TAbLE 1. APPROxIMATE AMOuNT IN TONS Of SALT ADDED PER hECTARE ThROuGh IRRIGATION uSING DIffERENT AMOuNTS Of wATER, ACCORDING TO ThE SALINITy Of ThE wATER uSED.
Most salts are highly soluble and remain dissolved when irrigation water is applied and percolates into the soil.
An environmentally sustainable agriculture in saline water and soil conditions must consider the possibility of applying washing fractions. The washing dose needed to keep soil salinity levels at a level that will not lead to a reduction of olive yields of more than 10% is:
ECiwLR = ---------------------- 5* EC10% - ECiw ECiw: electrical conductivity of irrigation water
EC 10% electrical conductivity in saturated-paste soil leading to a 10% harvest decrease.
Examples Of Different Irrigation-WaterSalinity Levels And Washing Needs
EC iw (dS/m)
1.5
2.1
3.5
Washing Fraction %
8.5
12.4
22.5
Sodium soils (CE < 2 dS/m, PIS > 7) show high sodium levels in the soil’s ex-change capacity in relation to calcium and magnesium, and degrade the soil’s physical properties.
Sodicity occurs when sodium ions are absorbed into clay and organic material particles. It directly affects the physical and chemical properties of the soil, leading to greater soil compacting, dispersion, hardening, crust formation and flooding. These conditions are inappropriate for root growth and limit plants’ water absorp-tion and respiration, leading to lower growth and yields.
Physically degraded soils that are watered using low-quality water tend to ac-cumulate more salts and provoke higher sodicity levels, thus reducing the soil’s
“In most irrigated plantations,
irrigation water is the main source
of salts in the root area”
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210X295_olint_USA 31-07-2009 16:39 Pagina 1
physical properties and generating a degrading cycle. Moreover, if the soil is cultivated intensively it may show signs of compacting and tillage pan. In such conditions flooding is more frequent, deep drainage is limited and salts tend to accumulate at a faster rate.
Infiltration problems caused by the sodicity of irrigation water also depend on the type of irrigation and soil management. When soil structure is weakened by the effects of sodium, spontaneous clay dispersion may not take place.
To recover such soils it is necessary to replace the sodium in the exchange capacity by adding calcium. Washing irrigation may have a negative effect, since it lowers the concentration of other salts.
Saline-sodium soils (CE > 2 dS/m, PIS > 7) show high levels of dissolved salts and a high percentage of sodium in the soil’s exchange capacity. To recover them, calcium must be added, followed by washing irrigation.
wAyS Of MANAGING SALINITyHigh concentrations of salts lead to a physical degradation of soil; the soil be-comes compacted, there is little aeration and flooding occurs. To improve the
TAbLE 2. GuIDE fOR INTERPRETING ThE quALITy Of IRRIGATION wATER. (AyERS & wESCOT 1994)
Degree Of Use Restriction
dS/m
mg/l
meq/l
meq/l
mcq/l
mcq/l
mg/l
mg/l
mcq/l
None
<0.7
<450
>0.7
>1.2
>1.9
>2.9
>5.0
<3
<3
<4
<3
<0.7
<5
<1.5
Light/Moderate
0.7 - 3.0
450 - 2000
0.7 - 0.2
1.2 - 0.3
1.9 - 0.5
2.9 - 1.3
5.0 - 2.9
3 - 9
>3
4 - 10
>3
0.7 - 2
5 - 30
1.5 - 8.5
Severe
>3.0
>2000
<0.2
<0.3
<0.5
<1.3
<2.9
>9
-
>10
-
>2
>30
>8.5
UnitsPotential Irrigation Problem
Salinity (Affects the plantations water availability)
Water EC
TDS
SAR Water EC
Specific Toxic Ions (They affect sensitive crops)
Sodium (Na+)
Surface Irrigation
Spray Irrigation
Chlorides (Cl-)
Surface Irrigation
Spray Irrigation
Boron (B)
Miscellaneous effects (Affecting sensitve crops)
Nitrogen (NO3-N)
Bicarbonates (HC03-)(Spray irrigation)
PH
Infiltration (Affects the ratio of water infiltrationinto the soil. Assess using water EC and sodiumabsorption rate, SAR, jointly)
0 – 3
3 – 6
6 – 12
12 – 20
20 – 40
Normal range 6.5 — 8.4
“when soil structure is weakened by the effects of sodium, spontaneous clay dispersion may not take place”
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210X295_olint_USA 31-07-2009 16:39 Pagina 1
8
soil’s mechanical properties and facilitate washing salts away from the root area, it is necessary to maintain and if possible create appropriate porosity (different sized pores) in the root area. Soils with the right physical structure are loose, well aerated, drain easily and provide adequate water retention for a plant.
Larger diameter pores play a fundamental role in drainage, aeration and root penetration (0.075–5 mm diameter). Smaller pores storage water for absorption by the plant (0.03–0.0005 mm), whereas extremely fine pores should be kept to a minimum (< 0.0005 mm). To achieve this kind of porosity, the following soil management strategies are recommended:
•Subsoiling (deep tilling) the soil when the moisture content is appropriate for breaking up compacted sods and creating small aggregates to improve deep drainage and root penetration.
•Add gypsum to reduce sodium content and improve drainage.
•Establish a green cover between planting rows during the winter months to maintain adequate porosity and improve infiltration and deep drainage.
•Avoid tilling the soil and machinery traffic•Consider making ridges/berms in planting rows to
increase root depth in the soil area with the lowest salinity levels.
•Avoid excessive irrigation, but irrigate sufficiently to wash away and control the accumulation of salts. Monitor drainage by using moisture sensors at dif-ferent soil depths and an additional sensor below the root area.
•Monitor annual salinity and sodium trends in each irrigation unit by taking soil samples. Samples should be taken at three different depths, for instance 0–12, 12–30, 30–45 inches. Soil salinity results, sodium and chlorine concentrations in leaf analysis, and soil mois-ture and water table levels will provide indications for good irrigation and salinity management.
Subsoiling to increase aeration and drainage.
Green cover to increase soil porosity.
Making ridges/berms.
0-2525-5050-75
Months
10/9
6
1.4
1
0.8
0.6
0.4
0.2
0
EC d
S/em
1.2
1.6
1.8
3/97
11/9
7
4/98
10/9
8
5/99
10/9
9
5/00
11/0
0
11/0
1
5/02
11/0
2
5/03
11/0
3
4/04
Salinity Levels
Depth
fIGuRE 2. vARIATION IN SALINITy LEvELS IN SOIL EC (DS/CM) AT DIffERENT DEPThS
9
Productive DevelopmentOrCHarD maNaGEmENT
alberto Hormazabal araya Ing. Agrónomo P.u.P
máximo Galvéz ahumadaIng. Agrónomo M.S.C. P.u.P
T his article will focus on the variables that influence an olive tree’s reproductive process under the super-intensive system and how they affect tree response,
since such variables are tools that can be and are used for different production purposes.
Olive tree flowers develop from a simple, lateral bud opposite another on the knot of the previous year’s stem, and produce a panicle inflorescence. The flower is occasionally apical and very rarely appears on second-year stems. It is also uncom-mon to find flowers from a mixed lateral or terminal bud in one-year stems, which leads to a flower sprout that is very characteristic of other persistent species.
Flowering is initiated due to a series of environmental stimuli and internal responses in the plant at a stage known as induction; these responses lead to a differentiation of the meristematic tissue at the bud, and if this differentiation does not take place, it leads to the generation of vegetative matter (stem and leaves).
The first event in the flowering process is floral induction (of inflorescence) which generally occurs in the season prior to flowering: the process lasts about 7 or 8 weeks from full bloom, and ends with the hardening of the fruit stone or pit. The floral induction stage can be negatively affected by an excess of fruit, which decreases the potential number of flowers and therefore the expected yield. This can be offset by thinning during ON years. Physiologically this effect is due to the direct inhibition of the seed (embryo) which produces inhibiting hormones (gibberellins). One method
of eliminating a flowering season or producing an OFF year is therefore to apply gibberellic acid (GA3) to stems between the end of spring and the beginning of summer or inducing synthesis by strengthening the plant. A contrary effect can be achieved by decreasing synthesized gibberellins in the roots by reducing or restricting irrigation, which prevent gib-berellin growth and therefore the centers of neoformation in the induction is also negatively affected by excessive shade, which is due to excessive plant growth generated by excess fertilization. If shading is produced early it affects induction and blooming, and if it is late, affects the development of inflorescence with sterile flowers.
Induction is also negatively affected by excessive shade, which is due to excessive plant growth generated by excess fertilization. If shading is produced early it affects induction and blooming, and if it is late, affects the development of inflorescence with sterile flowers.
The process of floral differentiation calls for a period of dormancy that requires a certain number of hours of cold. During this state of apparent absence of activity and growth,
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the induced bud goes through cellular changes that make up the actual pro-cess of floral differentiation of the flow-ers during inflorescence, which begins at the end of winter in post-dormant flower buds.
As a result of that process small, acti-nomorphic and symmetrical flowers with persistent greenish-white sepals, four yellowish-white petals, two op-posing stamens with short filaments and a large anther appear on the olive tree. Pollen develops six weeks prior to blooming; the ovary is superior with two locules, each with two ovules, and the embryo sac inside the ovary ma-tures some three weeks before flower-ing (incomplete development).
During the process of flower differentia-tion and development there is strong competition over assimilated nutrients, which has a negative effect on the pro-cess. Ringing watered, vigorous plants at the end of fall promotes greater and better flower differentiation (greater flowering).
The best-quality flowers are obtained through average winter temperatures ranging between 2 and 4°C (35.5–39°F) and a maximum of 15.5 to 19°C (59.6–62.2°F), since such temperatures do not stimulate plant activity or the expres-sion of growth. We can conclude from this that in sub-tropical climates the same effects of this temperature range can be achieved through cultivation management by reducing the nutri-tional content of nitrogen sources and limiting or restricting irrigation.
On individual branches, the inflores-cence consists of 1 to 4 flowers with a short peduncle, but can contain more than twenty. The flowers can be perfect (hermaphrodite) or with stamens alone (male), and these conditions depend on whether it is an on or off year and also on their location in the tree: the highest proportion of perfect flowers is found in the medium third of the floral shoot on the tree’s sunniest side.
Flowering occurs on short shoots which begin to develop naturally when vigor-ous growth of the branches on young trees diminishes, fruit forms on them, the original branch of two or more years’ age bends and a sucker sprouts, thus renewing the cycle.
When strong flowering takes place, the resulting fruit load lowers the level of free sugars (mannitol and stachyose) and reserve sugars (starch) in the branch, which affects the potential development of short sprouts where flowers should form. This nutritional deficit, which affects the following year’s flowering, can be mitigated by ap-plying amino acids, even though sprout growth may be greater as a result. A recommendable cultural practice for increasing blooming is ringing during the fall and winter, which momentarily sequesters in the crown the photo as-similates needed to form the next year’s flower-bearing shoots.
For flowering to take place both buds and the stem, but not the leaves, must be exposed to cold temperatures, the stimulus is not translocatable, and a daily fluctuation is more important than the total hours of cold temperature; trees exposed to a constant temperature of 7°C or 16°C (44.5ºF or 61ºF) practi-cally do not give flowers, and at 12.5°C (54.5ºF) (compensation temperatures)
produce only stamen (male) flowers, whereas a sinusoidal fluctuation of between 2ºC and 15°C (35.5°F–59°F) induces a good formation of perfect flowers, as mentioned above.
Vernalization is effective when growth has ceased and average daily tem-peratures stand at 12.5°C (54.5ºF), the average maximum at 18°C (64.5ºF) and the minimum at 7°C (44.5ºF) re-spectively for a period ranging between 17 to 22 days or the compensation point between fall and spring. A high winter temperature above 20°C (68ºF) for 2 to 3 weeks makes it difficult for flower buds to open and a high fruit load requires greater cold for flower expression. It has been pointed out that cold modifies the hormone content of flower buds, with increased gibberellins and a reduction in inhibitors: this does not occur in vegetative buds, since the highest level takes place at the end of the first month of spring, a little before the new sprouting; applying GA3 at that time promotes the development of in-florescence, whereas applying abscisic Ac inhibits it.
The accumulation of cold signals the end of flower-bud dormancy; the gib-berellin produced during the accumula-tion of cold stimulates the development of inflorescences and their sprouting. A deficiency of cumulative hours of cold makes buds abort due to incomplete development.
Most varieties of olive are partly self incompatible and their setting and yield improve with cross pollination. This self incompatibility arises because in adverse environmental conditions the vigor of the pollen tube diminishes, thus hampering the double fertiliza-tion of the ovule. Nevertheless, there is widespread evidence of highly self com-patible cultivars that do not require the support of pollinizers, among them the Picual (Andalusia), Chemlali (Tunisia) and Arbequina (Catalonia) varieties.
To improve the pollinization-setting percentage in partly self compatible varieties, it is advisable to provide good leaf nutrition using boron and calcium during the period from flower buds to 10% open flowers. Both elements help to establish proper elongation of the pollen tube, which culminates in the double fertilization of the ovule, since
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they help the synthesis and integrity of the plasma membrane and the physi-ological inactivation of the callous walls of the pollen tube, thereby inhibiting the response to pathogen resistance.
It has also been noted that since pol-linization is wind-borne, rows should be oriented to increase pollen liberation transport and capture, in such a way that rows face the prevailing winds at least during anthesis until fertilization. It should be borne in mind that stigmas are receptive for about 10 days, but the number of receptive stigmas reaches 80-90% for only two days. Ten percent of the flowers produced set, but only 2% reach the harvesting stage. The word olive means fruit with oil: it is a drupe 1 to 4 cm (.39 to 1.6 in) in length and 0.6 to 2 cm (.24 to .79 in) in diameter. Its cumulative development forms a double sigmoid curve which follows three well-defined stages.
During the first stage the endocarp is what develops the most before harden-ing, and is strongly affected by water affliction; the mesocarp grows consider-ably during the third stage, particularly with abundant watering, to form the oleic pulp.
Cell division lasts up to 6 to 8 weeks after flowering and the number of cells produced characterizes different-sized varieties.
The formation of a seed (one) is es-sential to the fruit’s normal growth, although parthenocarpy can take place leading to small fruit, without value, known as “zofairones”. The embryo starts to develop in 3-4 weeks after flowering and cotyledons are formed completely in 8 weeks.
Competition between the growth of all flowers and then between all the small fruit leads to a strong demand for nutrients, initially between the panicles themselves and then mainly between inflorescences, which produces abscis-sion for up to 6-8 weeks; non-pollinated and abnormal flowers fall off two weeks after flowering, when fruition reaches around 15%, without having an impor-tant effect on production.
Thinning out the fruit between 20 and 30 days after flowering reduces com-petition and favors the growth of the remaining fruit, which grow to a greater size. Conversely, thinning the flowers or inflorescences increases fruition but reduces the final size of the fruit.
Final fruition amounts to about 1-4% of total flowers.
Ringing carried out during the fall favors both fruition and the growth of fruit, whereas if it is carried out 30 days prior to flowering, it only benefits fruit growth.
Olive fruit hormones follow different patterns to those of other species. It has been reported that gibberellins diminish gradually until the end of the fruit growth or black coloring and that cytokinins increase as the fruit ripens, as in the case of kiwi.
The use of aminated compounds ap-plied during full flowering, or prior to flowering, has increased production in self compatible varieties, since these substances inhibit ethylene synthesis, thus reducing an undesired natural load adjustment.
Ethylene has little effect on growth and on olive ripening; in its natural form very little is produced, increasing a little towards the end of the maturation process. Nevertheless, it has a strong stimulating effect on fruit abscission, as do ethylene-generating products such as ethephon and cycloheximide.
ON year Off year
wind
pollen
Rows facing the prevailing wind
During an ON year, the excess flowering-setting determines a low replacement of potential inducing-differentiating buds, which means that the following year both flowering and yield will be poor (Off year)
Allowing a more balanced flowering-setting leads to lesser hor-monal inhibition and better distribution of photoassimilates, and therefore similar flowering-setting from one year to the next.)
flowersfruitshoots
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Flowering involves 3 well-defined stages, these being induction, bloom-ing and differentiation, which are gov-erned by endogenous and exogenous factors, the latter being relatively easy to manage.
Excessive shading affects the grove’s productive growth; if it takes place too early it hampers flower induction and blooming, and if late it hampers the development of inflorescence, produc-ing sterile flowers.
The process of differentiation and flow-ering provokes strong competition be-tween photosynthates, which can lead to defective flowers or excessive flower abortion: this can be offset through the cultural practice of ringing the trunk.
The best-quality flowers are obtained through winter temperatures between 2 and 4°C (35.5–39°F) and a maximum of 15.5 to 19°C (35.5–39°F).
Flowering occurs on short shoots formed during the previous season; in years of excessive fruit load the level of
free sugars (mannitol and stachyose) and reserve sugars (starch) drops, potentially affecting the development of productive shoots. This nutritional deficit can be mitigated by applying
amino acids and free sugars.
Pollinization-setting of self compatible varieties benefits from applying boron and calcium to foliar nutrition.
Photoassimilates are more strongly attracted by fruit, to the impairment of shoots.
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roberto ruilopeDirector of Agrolab Analítica, S.L.
rESEarCH
T he generalized belief that any kind of soil is suitable for olive growing is not borne out by the reality. Al-though this crop is well known for adapting to areas
with very different characteristics, this does not mean that it can develop fully anywhere, regardless of soil conditions, climate and other land factors. As with vineyards, soils with high clay, saline and/or gypsum content are not suitable for olive plantations.
Apart from watering needs one of the problems that most affects good olive-tree development is fertilization. This is traditionally done as a routine task, without taking into account crop needs or the type of soil where olive trees are growing. Fertilization should be planned in keeping with soil fertility, the plantation’s nutritional levels, the trees’ vegeta-tive condition, water availability in the soil, fertilization in previous years, the existence of visual symptoms that can
Leaf Diagnosisa method of monitoring Proper Nutrition in Olive Plantations
Olive trees have been adapted
to a wide range of soils and their
hardiness also enables them to
grow in very poor soils and sub-arid
climates. The number of plantations
has increased significantly for a
number of reasons. Olive production
has been stepped up through
greater tree density; drip irrigation
has become the norm and olive trees
are now being planted in marginal
areas not traditionally associated
with olive growing.
be attributed to nutritional deficiencies, and a plantation’s average yield both in pounds of olives and in olive oil.
Another important consideration is that new olive-tree grow-ing systems considerably increase nutritional demands and symptoms of deficiencies occur more frequently. All these factors mean that the plantation’s response to conditions that are often adverse is unknown, so additional controls need to be taken to achieve one’s aim in all agricultural activities and therefore in superintensive olive groves: maximizing profits by improving income through maximum quality production and keeping costs to a minimum.
In view of those considerations, determining the nutritional state of olive trees through leaf analysis or “leaf diagnosis” is an objective, practical method of programming fertiliza-tion by detecting nutritional anomalies and monitoring the
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plantation’s nutritional state and needs, to be in a position to program fertilization the following year.
LEAf DIAGNOSISThe information resulting from leaf analysis complements soil-analysis data, thus rounding out information on the set of factors that have a bearing on nutrient assimilation.
AIMS• Deciding on fertilization practices, mainly as regards
microelements, since it is difficult to determine their availability in the soil.
• Confirming nutritional alterations that have been diagnosed visually.
• Early detection of nutritional imbalances that do not show specific symptoms but translate into progres-sive reduction of tree strength or yield.
• Knowing to what extent the nutrients already in the soil or those added through fertilization are used by trees and validating and adjusting the fertilization plan.
SAMPLINGSampling is the first step in the process of leaf analysis, and it is crucial to meet a number of conditions for the end result to be valid, representative and comparative to ensure correct data interpretation.
SAMPLE-TAKING PERIODS AND TIMEfRAMELeaf composition changes as leaves develop, so sampling should take place during periods when the concentrations of the elements to be sampled are at their most stable. Fol-lowing-up on nutrient levels requires taking samples twice during the year, one in summer and the other at the end of winter. Certain circumstances in crop management may require additional sampling to verify how trees are respond-ing, but at least one sample a year should be taken:
1) Summer. The period from the end of June to the beginning of August, although the second half of July is preferable.
The data and information gathered during this period are the most useful since this is when olive trees are at their most important phase. Apart from suggesting corrections to previous fertilization campaigns, this period allows us to act in time to correct nutritional needs and ensure a good harvest in terms of yield and quality.
SAMPLE TAKINGIt is essential to sample a uniform area of the plot, where trees are visually similar, growing in the same kind of soil and subjected to the same growing techniques. It is impor-tant to ensure a standard sample that shows the average for the plot.
Sample taking depends on the type of tree guidance. In a traditional olive grove it is recommendable to cross the area to be sampled diagonally, and to pick leaves facing all four
directions – north, south, east and west. If trees are guided on a trellis in intensive or superintensive growing, the best approach is to sample several rows by taking exterior leaves from both sides and avoiding internal areas, since they re-ceive less light so their composition may differ.
Sampling should be avoided after applying leaf treatments or using growing techniques that could lead to variations in nutritional content.
PART Of ThE TREE TO bE SAMPLED AND quANTITy Of LEAvESFresh, complete, fully developed leaves should be picked, including the leaf stem, while avoiding severely damaged leaves or those with necrotic areas. Leaves should be picked around the tree in all four directions, at eye level, from shoots without olives chosen at random, ignoring shoots with strong vertical growth.
“Leaf composition changes as leaves develop, so sampling
should take place during periods when the concentrations of the elements to be sampled are at
their most stable.”
Figure 1. Olive tree leaf for sampling
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Pick leaves from a shoot (Figure 1) pertaining to the year chosen, located half way down the year’s shoot: the 3rd or 4th pair of leaves from the tip is preferable.
A minimum of 100 leaves should be picked per sample, preferably between 100-250 complete leaves picked ran-domly from some 60-100 trees.
SENDING Of SAMPLES TO ThE LAbPlace the complete leaves with stems, without pressing them, in PAPER bags or envelopes, although they can also be put in clean, open plastic bags without holes. They can also be wrapped in aluminium foil for better conservation. Whichever method is chosen, they must be labeled for easy identification.
Once picked, plant tissue decomposes rapidly and loses weight. It is advisable to send samples for analysis as soon as they have been gathered, while avoiding their exposure to sun and heat: keep the samples in a cool environment. If delivery to the lab takes longer than 12 hours, samples should be kept at a temperature of 4ºC.
The lab should be contacted in advance so as to know under what conditions samples should be transported while also establishing the conditions needed at the lab for washing and preparing them for analysis.
To determine the nutritional state once the content of the elements of greatest interest in olive tree leaves has been analyzed, we should compare results with reference values or levels.
The optimum nutrient levels for ol-ive-leaf samples picked in summer (2nd half of July) in accordance with the standards mentioned above are contained in Table 1, which shows the levels estimated by different authors, with minor differences.
For over five years AGROLAB has been conducting systematic research on leaf diagnosis in olive trees, thus adding to the extensive data gathered in vineyards using this kind of analysis and interpretation of results. A research and development project has led to the development of a work methodology to
“To determine the nutritional state once the content of the elements of greatest interest in olive tree leaves has been determined, we should compare our results with the
reference values or levels.”
OLIVAR MEDITERRÁNEO/Author Bouart-1955 Fernández-Escobar 1999
Determinations Units Minimum Optimum Maximum Deficient Adequate Toxic
Nitrogen (N) g/100g 1.01 1.77 2.55 1.40 1.5-2.0
Phosphorus (P) g/100g 0.5 0.12 0.34 0.05 0.1-0.3
Potassium (K) g/100g 0.22 0.80 1.65 0.40 >0.80
Calcium (Ca) g/100g 0.56 1.43 3.15 0.30 >1
Magnesium (Mg) g/100g 0.08 0.16 0.69 0.08 >0.1
Sodium (Na) mg/Kg >2000
Iron (Fe) mg/Kg 40.00 124.00 460.00
Copper (Cu) mg/Kg 1.50 9 78.00 >4
Manganese (Mn) mg/Kg 4.00 23.50 84.00 >20
Zinc (Zn) mg/Kg 5.00 36 164.00 >10 84.00
Boron (B) mg/Kg 2.00 11.7 24.50 14.00 19-150 185.00
OLIVAR MEDITERRÁNEO/Author Recalde 1975 Horticulture and Food Research Institute Soyergin 2002
Determinations Units Correct Height Deficient Optimum Excess Correct Height
Nitrogen (N) g/100g 0.68-2.20 <1.40 1.50-2.00 1.60-2.00
Phosphorus (P) g/100g 0.13-0.42 0.13 0.15-0.18
Potassium (K) g/100g 0.21-0.80 <0.40 0.80 0.60-0.90
Calcium (Ca) g/100g 1.00-1.51 1.50-1.80
Magnessium (Mg) g/100g 0.10-0.14 0.19-0.22
Sodium (Na) mg/Kg >2000
Iron (Fe) mg/Kg 90-130
Copper (Cu) mg/Kg 40-50
Manganese (Mn) mg/Kg 43070.00
Zinc (Zn) mg/Kg 80-140
Boron (B) mg/Kg <14 19-150 >185 12-16
Determinations Units Very Low Low Normal High Very High
Nitrogen (N) g/100g <1.40 1.40-1.60 1.61-200 2.01-2.50 >2.50
Phosphorus (P) g/100g <0.05 0.05-0.10 0.11-0.20 0.21-0.30 >0.30
Potassium (K) g/100g <0.40 0.40-0.60 0.61-0.90 0.91-1.10 >1.10
Calcium (Ca) g/100g
Magnessium (Mg) g/100g
OLIVAR MEDITERRÁNEO/Author Generalitat Valenciana. Integrated Yeild 2002
All results and reference values are for dry matter.
TAbLE 1. CRITICAL NuTRIENT LEvELS IN OLIvE LEAvES ACCORDING TO DIffERENT AuThORS
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Determinations Units Deficient Low Correct Height High Elevated
Balance N-P-K <2.1 2.1-2.5 2.5-3.0 3.0-3.5 >3.5
%N in the balance <53 53-58 58-63 63-68 >68
%P in the balance <4 4-5 5-6 6-7 >7
%K in the balance <27 27-32 32-37 37-41 >41
Antagonism K/Mg <3.8 3.8-6.3 6.3-9.4 9.4-11.9 >11.9
Antagonism Cations Divalents <0.2 0.2-0.4 0.4-0.7 0.7-1.0 >1.0
Vegetative ratio <0.35 0.35-0.70 0.70-1.1 1.13-1.49 >1.49
Nitrogen (N) g/100g <1.20 1.20-1.49 1.49-1.84 1.84-2.12 >2.12
Phosphorus (P) g/100g <0.09 0.09-0.13 0.13-0.17 0.17-0.21 >0.21
Potassium (K) g/100g <0.64 0.64-0.83 0.83-1.06 1.06-1.25 >1.25
Calcium (Ca) g/100g <1.00 1.00-1.64 1.64-2.40 2.40-3.04 >3.04
Magnesium (Mg) g/100g <0.10 0.10-0.12 0.12-0.15 0.15-0.18 >0.18
Sodium (Na) mg/Kg <120 120-173 <250 239-292 >292
Iron (Fe) mg/Kg <66 67-90 90-117 117-140 >140
Copper (Cu) mg/Kg <5 13636 37-91 91-135 >135
Manganese (Mn) mg/Kg <23 23-33 33-45 45-55 >55
Zinc (Zn) mg/Kg <12 42339 15-18 18-20 >20
Boron (B) mg/Kg <16 16-23 23-30 30-36 >36
All results and reference values are for dry matter.
TAbLE 2. CRITICAL OLIvE-LEAf NuTRIENT LEvELS, ACCORDING TO ThE AGROLAb DATA bASE
“The idea is to assess which values are most removed from optimum levels so as to correct them, since they can
also affect others that are at the right levels by decompensating them.”
interpret data with greater accuracy in our olive plantation and in superinten-sive cultivation in particular.
Using the above commonly used refer-ence values, we have gradually devel-oped an extensive data base based on our analyses of recent years; this has strengthened year-on-year information on olive-leaf intervals and critical nutri-ent levels, as shown in Table 2.
Each new analysis is leading to more statistically significant data on estab-lished intervals, which may or may not help to strengthen the data base. If the differences for each nutritional element under analysis are within acceptable ranges, they will be included, modifying those intervals as applicable on gather-ing variables due to differences in soils, different weather conditions, availability of water in the soil, tree conditions, dif-ferent crop management, etc.
Information on other values and relationships between the different
elements under analysis is also being collected to improve data interpreta-tion. Thus, high values in the vegetative ratio indicate that the balance between nutrients is being decompensated, with higher nitrogen, phosphorus or potassium levels or all at the same time, and weaker or barely sufficient calcium and/or magnesium levels, leading to greater plant growth which can com-promise yields.
Next to those figures are ratios for each of the essential nutrients, which show us which elements have deficient levels or those that are decompensated through deficiency or excess, which will have repercussions on nutrition in other fundamental levels.
In the final analysis, the aim of this methodology is to assess which val-ues are most removed from optimum levels so as to correct them, since they can also affect others that are at the right nutritional levels by decompen-sating them.
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ExAMPLE 1. PITILLAS, NAvARRAOne of the first intensive olive planta-tions in the area was showing a general lack of growth, although the problem was worse in the eastern half of the plantation. Two batches of leaf samples were taken, separating the better devel-oped area from the half showing clear
Figure 2: Example of leaf samples in Pitillas, Navarra.
CLIENT: Agrovanguardia, S.LAPPLICANT: Emilio LorenteSAMPLE: Leaf/FoliarCROP: OliveVARIETY: ArbequinaLOCATION: Pitillas (Navarra)SAMPLING DATE: 7/23/2008
Proper Development Drier, Yellower Plant
LIMITATIONS Of DATA INTERPRETATION
Although the information it provides is very useful, this type of analysis only shows which nutritional elements are required and must be incorporated into our fertilization plan. It does not automatically tell us the amount that must be added to the soil or irrigation water, or the best way of applying it.
Identifying a lack or excess of a given element is just the first step in recommending the kind of fertilization required. This depends on soil char-acteristics, its fertility, the plantation’s general nutritional state, the trees’ vegetative condition, water availability in the soil, fertilization in previous years, the existence of visual symptoms that can be attributed to nutritional deficiencies, the quality of irrigation water, and the plantation’s average production level.
Determinations “Normal”Development Assessment Yellowish
Olives Assessment Deficient Low Adequate High Elevated
Nitrogen (N) 1.46 Low 0.91 Very Low <1.20 1.20-1.49 1.49-1.84 1.84-2.12 >2.12
Phosphorus (P) 0.13 Low 0.14 Adequate <0.09 0.09-0.13 0.13-0.17 0.17-0.21 >0.21
Potassium (K) 0.59 Very Low 0.73 Low <0.64 0.64-0.83 0.83-1.06 1.06-1.25 >1.25
Calcium (Ca) 2.35 Adequate 1.91 Adequate <1.00 1.00-1.64 1.64-2.40 2.40-3.04 >3.04
Magnesium (Mg) 0.19 Excess 0.14 Adequate <0.10 0.10-0.12 0.12-0.15 0.15-0.18 >0.18
Sodium (Na) 279 High 260 High <120 120-173 <250 239-292 >292
Iron (Fe) 210 Excessive 232 Excessive <66 67-90 90-117 117-140 >140
Copper (Cu) 12 Low 16 Low <5 13636 37-91 91-135 >135
Manganese (Mn) 39 Adequate 30 Low <23 23-33 33-45 45-55 >55
Zinc (Zn) 12 Low 13 Low <12 42339 15-18 18-20 >20
Boron (B) 20 Low 19 Low <16 16-23 23-30 30-36 >36
TAbLE 3. INTERPRETATION Of RESuLTS Of SAMPLES TAKEN IN PITILLAS, NAvARRA
deficiencies, poor development and strong yellowing, with leaves showing symptoms of dryness, as can be seen in Figure 2.
The analysis (Table 3) shows a general lack of CALCIUM which is hardly nor-mal in a chalky soil, so the lack of cal-cium in the leaves shows that the root
system is not functioning properly and is therefore not providing the necessary nutrients at the required rate.
The problem applies to the entire plot but is worse in the yellowing area, which is in an area where such soil problems are greater.
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GRAPh 1. bALANCE Of ESSENTIAL NuTRIENTS. SAM-PLE PLANTATION wITh PROPER DEvELOP-MENT IN PITILLAS, NAvARRA
GRAPh 2. bALANCE Of ESSENTIAL NuTRIENTS. DRIER, yELLOwER SAMPLE IN PITILLAS, NAvARRA
TAbLE 4. INTERPRETATION Of SAMPLING RESuLTS fROM MENDIGORRíA, NAvARRA
The curve in Graph 1 shows the average value of the dif-ferent reference values (green), which serve as a reference and/or base line for comparing the sample data, in orange. The higher values expressed above the green line show the excess nutrient in the balance. The lower values, below the dark orange line, show the deficiency or lack of each nutri-ent in the balance.
The soil is excessively compacted, perhaps due to excess humidity and water, and has a strong, heavy texture rich in mud and clay, which lead to root asphyxiation and weaken the tree. Essential nutrients are lacking due to sluggish root activity. As shown in Table 3 and as is also reflected in Graphs 1 and 2, the most important deficiency is the visually appar-ent lack of nitrogen in the sample, associated to a marked weakening and a general lack of trace elements, although not too decompensated.
We recommend improving the soil’s properties by facilitating aeration through deep tillage with a subsoiler, ending in the part of the plot where excess water drains out naturally, and ensuring that the coulters pass through the areas of greatest soil compacting due to the frequent passage of machinery.
That task, which we consider crucial, should also include applying elements such as root development activators, aminoacids, humic acids, etc., to the soil to improve the plantation’s general development.
ExAMPLE 2. MENDIGORRíA, NAvARRAAs in the previous example, in this plantation in Mendigor-ría, Navarra, the leaves on a high percentage of olive trees were also yellowing. Two samples were taken, separating the area with poor development from another sample area we defined as “normal”, where leaves from trees with no appar-ent symptoms were taken from the ground. (Table 4)
Values shown in green indicate the reference value estab-lished by AGROLAB as the average of the optimum interval for each nutrient. The normal sample is shown in dark
orange, to the left, and the yellower olive trees are expressed in light orange in the middle.
Determinations proper Developmemt Assessment Drier
Yellower Assessment Deficient Low Adequate High Elevated
Nitrogen (N) 1.54 Adequate 0,98 Very Low <1.20 1.20-1.49 1.49-1.84 1.84-2.12 >2.12
Phosphorus (P) 0.14 Adequate 0,18 High <0.09 0.09-0.13 0.13-0.17 0.17-0.21 >0.21
Potassium (K) 0.74 Low 0,97 Adequate <0.64 0.64-0.83 0.83-1.06 1.06-1.25 >1.25
Calcium (Ca) 1.76 Adequate 1,59 Low <1.00 1.00-1.64 1.64-2.40 2.40-3.04 >3.04
Magnesium(Mg) 0.16 High 0,11 Low <0.10 0.10-0.12 0.12-0.15 0.15-0.18 >0.18
Sodium (Na) 299 High 196 High <120 120-173 <250 239-292 >292
Iron (Fe) 97 Adequate 91 Adequate <66 67-90 90-117 117-140 >140
Copper (Cu) 200 Excess 234 Excess <5 13636 37-91 91-135 >135
Manganese (Mn) 36 Adequate 29 Low <23 23-33 33-45 45-55 >55
Zinc (Zn) 15 Low 14 Low <12 42339 15-18 18-20 >20
Boron (B) 8 Very Low 14 Very Low <16 16-23 23-30 30-36 >36
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We have circled the elements that show differences against the optimum reference value; the entire plantation shows a general, marked potassium deficiency, which is stronger in the olive trees considered normal. There is also a strong deficiency of nitrogen content, which is more marked in the yellower sample.
Conversely, iron levels are too high and disproportionate, and may generate a significant imbalance. This is a clear example that analysis of iron content in leaves, in this crop and others, is of little use, since paradoxically the level is much higher in more chlorotic leaves than in those considered normal. We
should not dismiss the possibility of a possible erroneous diagnosis, whereby efforts have been made to correct an apparent iron deficiency through chelates, when everything indicates that the problem is not due to a lack of iron.
In this case it would be advisable to correct the imbalance through fertilization to make up for the lack of potassium and nitrogen and subsequently –or as part of the same treat-ment—improve the plantation’s overall nutrition by applying a 2:1 mixture or solution of manganese and zinc to the leaves. This would correct the deficiencies in those elements that are present throughout the plantation.
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High yield, Low Cost and Best Oil QualityWhat can it do for you
Dr. Steffen m. HruschkaProduct Manager, GEA westfalia Separator Process Gmbh Phone +49 2522 77-2220, [email protected]
T raveling around the world, from ancient olive oil pro-ducers to the youngest olive oil nations, there is one feeling you get everywhere: nearly every producer is
very proud of his product and the slogan “This is the best oil of the world” is omnipresent.
No matter if the owner of the mill is a business man or an idealist, a scientist or a cook, a son of an olive dynasty, an aristocrat or a newcomer, everybody has to make at least a little profit. That means people measure the volume of oil they get from their olives, they estimate the production costs and they check the oil quality and the market in order to achieve the highest prices.
This article is written as a tool to help ease the mill owners’ life. It is not intended to compete with all the literature which has already been published.
KEEP AN EyE ON ThE RAw MATERIAL Given that I am working for an olive line producer let me focus this article on the oil room. Of course, the oil miller can only maintain the oil quality he gets from the oil-containing olives, but on the other hand he has to keep this quality. As-suming that the planting was right, the harvesting was also at the right moment, then it is most important to have the right logistics between harvesting and processing.
The quantity of harvested olives has to match the processing capacity. It is a beneficial, if the capacity of the mill is not limited to the volume of olives which are delivered to the mill or, vice versa, not more olives are harvested than the olive mill capacity permits.
Sometimes there is a need to store olives. In that case it is always better to use small units like bins, sacks etc., instead of big silos. The cold fresh air should circulate instead of having big tanks where the olives easily get damaged from the weight of the fruits stacked above. If these olives are damaged, fermentation will commence automatically. That is, enzymes find ideal conditions and start to split the fatty acids from the oil, meaning the olive oil Triglycerides are
OLIVES aND OLIVE OIL
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sometimes reduced to diglycerides and free fatty acid (FFA). But the free fatty acid (FFA) content is strictly limited, by IOC standards, to be less than 0,8% for “Extra Virgin”.
Fermentation also means changes in the aroma of the oil. And the higher the temperature, e.g. in the storage tank, the easier this will occur. But in practice, we also find excellent olive oil extracted from healthy olives stored in bins for 3-4 days, in the shade, in a cool environment. Furthermore, differ-ent fruit qualities should be processed separately.
PREREquISITEwAShING AND CLEANING Depending on the harvesting method the volume of impurities will vary. So, for instance, olives collected with a mechanical harvester contain consid-erably more leaves than olives struck down with bars and collected from the ground. If the ground is covered with grass the olives are normally cleaner
than when collected from earthen ground. This can be seen even more clearly if the ground is very clayey. Olives sucked from the ground with a vacum often contain many small, dry sprigs. Given that the density of the wood is similar to the density of the oil, even the clean oil phase will con-tain sprig particles left in the oil phase throughout the process.
The cleaning steps are as follows, de-pending on the harvesting method: In the first stage it is essential to remove the leaves with the leave blower-clean-ing machine prior to crushing. Should there be too many leaves left in the product, oil-soluble components such as the green chlorophyll, bitter agents and waxes, originating from the leaf surface, will also seep into the oil. That impairs the taste and overlaps the typi-cal taste of the variety.
In the second stage, the goal is to rid the olive surfaces of dust or sticky clay (when processing earth-collected olives) and of microorganisms adher-ing to the olive skins, using a washing machine. This is why a clean wash water in the washing machine essential for obtaining a pure oil. For very dirty olives, experience has shown that the water should preferably be cleaned of its coarsest impurities by passing it through external settling tanks. Nor-mally, it will be sufficient to change the cleaning water once a shift or once a day. Too heavily soiled olives will
convey sand particles into the decanter. Sand, in turn, can give rise to wear which ends up as a repair cost.
EvERy OLIvE MILL CuLTIvATES ITS TyPICAL AROMA Once the olives are cleaned, they are transported into the oil room as olives or as a paste after crushing. Let me comment the oil room in general first. Closing my eyes, I still remember the smell of all many mills I have visited around the world. It is quite similar to the wineries. That is, if you step into a winery, each one smells differently. And if you open a bottle of wine, that smell comes out of the bottle. No matter if it is Chardonnay, Riesling or Cabernet Sauvignon - the fragrance of the cellar is caught in the bottle.
And that is similar to the olive oil pro-cess. The aroma substantially depends on factors including cleanliness in and around the premises of the oil mill. This means that it is absolutely necessary for all the machines and plants to be easy to clean.
AN ART IN ITS OwN RIGhT: CRuShING AND MALAxINGPreparing the mash comprises crushing and malaxing. In the crushing step it is important to reduce the olives to par-ticles as fine as possible and to prevent emulsion. For this purpose the mesh size has to be adapted to the product and water might need to be added. The individual mill type or whether to use one or two perforated plates, disks, etc is, however, less essential. Minor oxygen absorption can never be absolutely excluded because an interior surface is always created.
The purpose of malaxing is to create conditions where the fruit-inherent enzymes will soften the cell walls. The material mass is moved in such a way that the cells are broken up and the oil droplets thus released are united to form a continuous phase. The oil-in-wa-ter emulsion (fine oil droplets are found in the fruit water) must be transformed into a water-in-oil emulsion containing a supernatant oil phase that still holds water droplets.
The general rule is: the longer the malaxing time, the more aroma com-ponents will be disintegrated. In the same manner that an apple turns
Every olive mill cultivates its typical aroma
An art in its own right: crushing and malaxing
“This is the best oil of the world”.
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brown after having been cut, because the polyphenols get oxidized, the olive paste oxidizes as well; part of the poly-phenols which essentially support taste and shelf-life properties are destroyed. Under these aspects even inert gas blan-keting will fail to be helpful because air has penetrated into the mass as early as the crushing stage. But assuming that everything has been done correctly, gas blanketing will have a positive effect on the yield as well as on the oil quality.
This means that the malaxing concept has to be technically implemented in such a way that the process steps can be configured variety-specifically, and quantity-specifically in a batch process respectively, within a very short time. Even the best decanter will only be able to compensate for part of the yield loss that results from insufficient malaxing. Any loss in quality will be irreversible. INTENSIvE, MILD TASTE IS ObTAINED by uSING 2-PhASE TEChNOLOGy In the past, olives used to be crushed, stirred, slightly heated up, pressed by means of hydraulic column presses, and then the press juice was split up into oil and water phase by means of small disk centrifuges or static sedimen-tation vessels: a very time-consuming procedure with low capacities.
In the early nineteen-eighties, more and more decanters and high capac-ity separators were used. This 3-phase technology consisted in diluting the olive mash with water in order to reduce the viscosity. The decanter separated the mash into the valuable oil phase, coarse-particle loaded effluents and the pomace. This was an economi-cally attractive, continuous process, but generated relatively large volumes of effluent.
In the early nineteen-nineties, GEA
Westfalia Separator introduced the 2-phase system which needs consider-ably less or even no water additions and produces less effluent. Today, this method is getting established to a larger and larger extent. For the 2-phase separation process, GEA Westfalia Separator developed a decanter with a special scroll separating the mash into oil and pomace.
Olive oils produced by way of the 2-phase technology generally have a more intensive taste due to the lower water volumes added, and thus less flavor-bearing substances and components get washed out.
For plant owners who for certain rea-sons want to make use of the 2-phase process as well as of the 3-phase pro-cess, GEA Westfalia Separator devel-oped a dual-purpose scroll enabling both techniques to be implemented. Conversion of this special scroll merely takes one hour. And there will not be any changes in yield or throughput when comparing this process to a pure 2-phase or 3-phase scroll con-figuration.
The decanter process can be comple-mented by a downstream separator acting as oil polisher. This separator requires only small volumes of water, produces very small oil loss, is self-cleaning and noticeably enhances the olive oil quality. The essential feature is the self-ejecting function. For an ejec-tion the bowl has to open and close. The crucial point is: the opening times must be extremely short so that no oil can escape or can get lost with the eject-ed solids. It is also the polishing-water volume that has to be kept as small as possible in order to prevent the oil from being washed out. It should go without saying that these technical challenges can only be met with a highly efficient separator.
The bottom line is that the yield contin-ues to be the most important parameter in the olive-oil recovery process – of course, along with the required quality standard and with the storage capabil-ity needed. A very important benefit of the 2-phase process is its function with-out water. In a 3-phase process, part of the polyphenols get washed out of the oil with the water phase. Another posi-
tive feature of this process is its stability even when having to process different raw materials - an habitual challenge faced in oil mills.
GEA Westfalia Separator is well known to be a provider fulfilling these criteria, the yield obtained with the processes is excellent, the stability of the processes is very high, and the quality of the oil obtained is recognized as ‘best of class’ and all this with a fair price/perfor-mance ratio..
Although GEA Westfalia Separator is undoubtedly capable of supplying best class equipment for the recovery of high quality olive oil, the best know how will be of no avail unless it is properly imple-mented. And this implementation can only be successfully achieved in close cooperation with the customer, and with the passion of the oil mill owner praises his product: “This is the best oil of the world.”
“This is the best oil of the world”
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Most olive oil industry operations have a common goal in mind. Produce an outstanding, recognizable product with a well, thought out plan and part of
that plan must be harvest.
Throughout the world, olive oil production has been a way of life for many – from planting and nurturing the trees, to milling or extracting the oil from the olive. For most of olive production history, hand labor has been a way of life from start to finish, involving all members of a family and many town folk plus hired labor to assist in the production and har-vesting. With the growth of world population, the demand for olive oil has increased, with the most dramatic demand over the past 10 years. Not only has olive oil become more popular for cooking and consumption, it has been proven that there are more and more health benefits, thus increasing the push for further production of olive oil around the world.
Today, many of the largest operations throughout certain areas of the world, produce and harvest olives mechanically. Standard machine operation procedures now include land preparation, post installation and trellising, tree planting, trimming and weed abatement. No longer are there hundreds of hands manually tending to the huge trees and the crops, as had been done in times past. The harvesting of olives, which
was once done entirely by hand, has more recently (in the last 30 years) employed the gigantic machines for picking the somewhat smaller trees. The more intensive High Density systems (20 feet by 20 feet) and even higher density plant-ings (16 feet by 16 feet) use machines that are very large and complex and which are very expensive. These are or have been considered more modern systems. However, in many areas, these somewhat intensive systems are still harvested by some sort of hand held shakers and rakes which take many hands to get the olive crop harvested and to the mills. Surprisingly, or maybe not, there are many of these systems still producing olives for oil production in many parts of the world today.
Now something new, even more intensive systems that have been planted world-wide including California and Chile. This more intensive system is simply called “Super High Density Olive Systems” (SHD). There are several planting spacings being used, but most range from 5 feet to 7 feet in the rows with row spacing from 12 feet to 14 feet being the most com-mon row widths. The main varieties are Koroneiki, Arbosana and Arbequina. These newly developed olive plantings allow for the farming of these SHD olive systems to be much more “equipment friendly” and boost the mechanical means of the operation to nearly 100%. While there are still some certain pruning that may need to be done by hand, most all operations are accomplished with some type of machine, including harvesting.
These systems have only been in the United States for a short time. The SHD was first planted at the California Olive Ranch near Gridley, CA in 2000.
This initial planting was harvested first with Gregoire G-120 Grape Harvesters operated by North Coast Harvesting and a
Super High Density Olivesmechanical Harvesting
CuLTIVaTION
Dave aldenCalifornia Sales, blueline MfG and Equipment
west Coast Importer for Gregoire harvesters
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Braud 680 that was leased by California Olive Ranch in 2004. To my knowledge, these were the first machines ever to harvest Super High Density olives in the United States.
Prior to that first mechanical harvest, not much was known about many aspects of the harvest with machines, at least here in California. The number one lesson learned from this experi-ence was that, harvesting olives takes a
lot more time to harvest and requires a lot more energy to pick in comparison to harvesting grapes. Until that time, grapes were the only other crop picked with a grape harvester.
These harvesting machines literally shake the daylights out of the trees and branches to get the olives off the trees, into the gondolas or bins which then go directly into the presses. This operation worked pretty well actually.
These grape harvesters are equipped with bow rods that squeeze down on the trees and shake back and forth about 460 shakes per minute to shake the olives off and out of the trees. The olives fall onto the floor (catcher assem-bly) then roll into the conveyor belts that carry the olives to the top of the machine where fans clean off the leaves and sticks and then are transported on another conveyor out to the gondola being pulled along side by a tractor. Not really all that complicated.
However, while machine harvesting was beginning to happen here in California, other olive growing operations, mostly in Spain were using grape harvesters, of various brands, to use in both grapes and olives. While these worked with a high degree of satisfaction there were some problems that came to light.
1)The first problem was; the young trees are susceptible to marking on the bark from different parts of the picking or collecting sys-tem from these grape harvesting machines and it’s advisable not have any or at the least, very little barking or damage to the limbs and especially the trunks, and there was some.
2)The second problem was; the tree structures were growing so rapidly that the large wood de-veloping in the trees were ham-pering some of the shaking and the harvesters were breaking off some of the large limbs. ( Some of that will happen anyway). Plus, these grape machines just did not do the best job in these “getting larger” trees.
3)The third problem; these super high density systems, while they seemed to be compact, liked to grow to height in about 3-4 years and constantly trimming or pruning the new growth back, was a needed or “have to” situa-tion because the grape harvesters that were being used, no matter what brand of harvester, were only 7 ft tall (some less) on the picking head and now height had became an additional handicap.
The Gregoire Harvester Company in France was extremely involved in the Spanish SHD olive oil operations early on in the new system developments.
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The Gregoire Company was studying these harvesting needs and devoted an engineer to develop a machine that would accomplish all the needs of this new SHD system.
The prototype machine was built with a lot of adjustable features to allow for learning what was going to be needed in a production model.
After 3 years of field development, the current Gregoire Olive Harvester was put into production, the Gregoire G 167. While other harvester companies have looked at the new olive indus-try evolution with little emphasis in addressing a new larger machine, in 2005, 2006 and 2007 there were many of the new Gregoire G 167 machines dispatched to Super High Density Olive operations throughout Spain. Since then, these new olive oil production op-erations in Portugal, Morocco, Greece, Italy, Chile and the US have all engaged this new taller and wider, more power-ful Gregoire Olive Harvesting machine for picking olives, in these new SHD systems. It was the only way. In the past year some of the other harvester companies are again looking at the olive oil plantations and working on design possibilities for picking the new SHD systems. The Braud company for one, is planning to have a demo machine out sometime for the 2009 harvest season and the AGH company in California also has a working model that’s taller for olives.
So after that explanation, harvesting olives doesn’t seem so complicated after all…..does it? In theory it really is not complicated and after all, doesn’t everything work in theory?
During this past harvest season there have been a lot of observations, of coarse some of these are partial ob-servations of mine. Lets start with the basics. Most grape harvesting machines will pick olives at least when the trees are young, just remember not to mark up the trees.
But wait, there are a lot of other condi-tions. Here are some questions that could be asked;
“Will the trees fit in the harvester and still get the olives off the trees?” Simply ex-plained, maybe- but not all. Some may
and some may not. That will depend on the trees, the variety and the timing and there could even be more variables.
“My operation has long skirts full of olives, what machine will do that?” That issue will probably take some trial and error. Some of the machines used to date will not pick the skirts well or not at all. Some grape harvesting machines have lower collections systems that will pick low hanging olives. If that is not an op-tion then an operation called “skirting the trees” might be advised to basically cut off that part of the production area and move the lower part of the tree higher. This operation however, will cut off some of the production area.
“Our trees are nearly 12 ft tall to the top of the new growth. What machine will do that and or how much will we have to trim off?” Very good variable question. Right now if using a grape harvesting machine, the hardwood part of the tree (where it has been repeatedly topped) cannot be higher than the maximum picking height of the actual picking head. The new growth can then be taller. It will be best to trim the new growth back at sometime prior to harvest, to reduce the amount of vegetation that goes through the machine. Experience will be the best gauge.
“We have some real big limbs in our trees,
what machine will do the best harvest for us?” I would have a biased opinion on that questions, however, for any ma-chine there will be some limitations. If the trees have not been pruned or trained properly and not pruned for machine harvesting it would be logical to expect a poor job of harvesting and fair amount of broken limbs.
“Is our maturity going to allow us to har-vest with any machine?” Maybe or maybe not. There is a point early on that olives can just be too green and immature. Possibly when maturity is that little, the oil content will be too low to be economically justified to harvest.
“If I water more or less does this effect the harvesting?” I don’t know the answer but it is being looked at to aid in better harvesting conditions.
“We saved a lot of money last year because we did not prune, can we use a harvester to pick?” Hard to say without looking at the orchard. If there is too much big heavy wood some or all harvesters may have a problem. For sure the likely hood of breaking more limbs exists along with some chance of a diminished job of shaking all the olives out of the trees.
Harvesting can be challenging. Every year may prove to be a bit different
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Wasco 661-758-4777
Paso Robles 805-237-8914
Modesto 209-523-8036
Santa Rosa 707-542-5510
800 • 499 • 9019 www.VintageNurseries.com
Vintage Nurseries Is Now OfferingSuper-High Density Olive Trees
The nursery you’vegrown to rely upon isnow growing anotherquality product.Vintage Nurseriesintroduces NursTechsuper-high density(SHD) olive trees inthree popularvarieties! Offeringversatility fordifferent soil andclimate conditions,they reflect ourdedicated philosophyof better quality,prices and service.Call Vintage today forour current list ofolive tree prices andavailabilities. And seehow many ways youcan benefit from thefruits of our labor.
ArbequinaSweet-style extra-virgin olive oil.Delicate and fragrant, with intensefruitiness but low levels ofbitterness and spiciness. The oil isharmonious and can be marketedas a single variety or blended.
Koroneiki i-38A green-style extra-virgin oliveoil which is very complex andwith high stability. It ispersistent and high inastringencies. The oil has acharacteristic dark-green color.
Arbosana i-43Green-style extra-virgin olive oil with a strong character,harmonious in aroma and highlevels of bitterness, spicinessand astringency. Persistent.
Tree Varieties
NursTech: The only source of certified origin olive trees in North America
052-VINTAGE NURSERIES_8-27x11-69clr_VN 10/30/09 9:19 AM Page 1
but some things we do know. Every area and block seems to have it’s own personality. What might work perfect in Corning may not work perfect in Gridley or Lodi or a hillside in Spain or rolling hills in Greece. There is going to be a lot of learning involved.
We do however, know a few things. Skirts are fine and in fact add a lot of production in the early years as long as the machine being used for harvest is able to pick them up and process that part of the tree. On some har-vester machines the collection system is just not built to go down that low.
In this case, the only options are to waist the production from that part of the tree or prune off those low parts. That could affect an easy 10%-15% of the crop, so choosing the correct harvester could mean a lot. As olive trees get older, pruning out the heavy wood and keeping the trees more supple and “fluffy” will aid some in better harvesting. Taller trees don’t develop the large wood as rapidly, so there should be some benefit from taller, somewhat thinner trees V.S. trees that are cut
back severely year after year.
In fact, I speculate, taller trees will equal more production and if the taller trees are picked with an olive harvester able to pick the skirts on the bottom that should result in a significant increase in overall production.
There maybe some other un-thought-of variables at harvest. Take for instance soil conditions. Rocky areas are going to mature at different times than deep soil. Not profound, but when it comes to harvesting with machines, and part of the field or row is ready and part is not, don’t expect to get all the olives off the
immature trees. Rolling hills may have some interesting spots in them at har-vest. And at the end of the day maybe something as simple as “day harvest” V.S. “night harvest” could make all the differences in some varieties in some area under some type of pruning style with some special irrigation regime. We just don’t have all the answers today.
The whole SHD system for olives har-vesting story has yet to be written. The first chapter has been the planting. We are now in the second chapter, the learning phase where narrowing the variables for growing the right kind of olives for premium oil production. The third chapter has also begun. The mechanical harvest for Super High Density Olive Systems.
This was a very brief summary about mechanical harvest for Super High Density Olive Oil Production. It’s a little clearer than mud. We have already learned a lot but we still have a lot to learn.
��
Wasco 661-758-4777
Paso Robles 805-237-8914
Modesto 209-523-8036
Santa Rosa 707-542-5510
800 • 499 • 9019 www.VintageNurseries.com
Vintage Nurseries Is Now OfferingSuper-High Density Olive Trees
The nursery you’vegrown to rely upon isnow growing anotherquality product.Vintage Nurseriesintroduces NursTechsuper-high density(SHD) olive trees inthree popularvarieties! Offeringversatility fordifferent soil andclimate conditions,they reflect ourdedicated philosophyof better quality,prices and service.Call Vintage today forour current list ofolive tree prices andavailabilities. And seehow many ways youcan benefit from thefruits of our labor.
ArbequinaSweet-style extra-virgin olive oil.Delicate and fragrant, with intensefruitiness but low levels ofbitterness and spiciness. The oil isharmonious and can be marketedas a single variety or blended.
Koroneiki i-38A green-style extra-virgin oliveoil which is very complex andwith high stability. It ispersistent and high inastringencies. The oil has acharacteristic dark-green color.
Arbosana i-43Green-style extra-virgin olive oil with a strong character,harmonious in aroma and highlevels of bitterness, spicinessand astringency. Persistent.
Tree Varieties
NursTech: The only source of certified origin olive trees in North America
052-VINTAGE NURSERIES_8-27x11-69clr_VN 10/30/09 9:19 AM Page 1
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Olive (Olea europaea L.) is considered drought toler-ant and trees can survive on shallow soils with little supplemental water beyond winter rainfall. The
economic survival of the orchard operation does not depend solely on survival of the trees. Maximizing oil yield and qual-ity are key components of oil olive production that must be maintained if an orchard is to remain economically viable. Adequate water is critical to maintain orchard productivity since olive is extremely responsive to irrigation in terms of maximizing shoot growth, fruit size, fruit yield and total oil yield per acre.
OLIvE PhySIOLOGyOlives bloom and bear the crop on one year old shoots. With a notorious tendency to produce a heavy crop one year followed by a light crop the following year, the produc-tion of annual shoot growth is critical to help even out the olive trees natural alternate-bearing tendency. Adequate soil moisture provided as either rainfall or irrigation during the spring helps generate new shoot growth for the following year’s bloom and fruit production. In addition, olive flowers are developing on the one–year-old shoots in early spring so avoiding moisture stress during that time helps develop a stronger bloom. Adequate moisture throughout the bloom period helps improve fruit set during the current year. Studies have confirmed that water management affects many physi-ological processes and characteristics of olives from year to year, including infloresence growth, the percent of perfect flowers, and fruit set. Dr. Hartmann of UC Davis showed that inflorescence growth can be reduced from twenty to twelve mil-limeters when trees are continuously moisture stressed during March. In addition, the percentage of perfect flowers (those capable of setting a fruit) and the percentage of fruit set were reduced dramatically by water stress during this critical month
(Hartmann and Panetsos, 1961). This illustrates the need for a carefully planned irrigation strategy to optimize the perfor-mance of olive trees particularly under drought conditions.
OLIvE wATER uSEBefore any sort of regulated deficit irrigation strategy can be managed the timing and amount of what constitutes full olive irrigation must be understood. Water is lost from an olive orchard to both evaporation and transpiration (the combination of which is referred to as evapotranspiration, or ET). ET is affected by a myriad of fac-tors, including humidity, temperature, wind, solar radiation (day length), and the percent canopy cover (the percentage of ground shaded by trees). Reference evapotranspiration (ETo) is based on the ET of a reference grass crop. To acquire real time ETo data through the previous day visit the Department of Water Resources California Irrigation Management Infor-mation System website: www.cimis.water.ca.gov. You’ll note that the ETo in figure 1 below is driven by both day length and temperature and is highest in July followed closely by June and August.
fIG. 1. AvERAGE MONThLy REfERENCE EvAPOTRANSPIRATION (ETO)
Water management For Oil OlivesCuLTIVaTION
Joseph Connell, farm Advisor, university of California Cooperative Extension, Oroville, California
Stephen Grattan, Plant-water Specialist, Dept. Land, Air, and water Resources, university of California, Davis
maria Jose Berenguer, formerly visiting scientist, Dept. Land, Air, and water Resources, university of
California, Davis
Paul Vossen, farm Advisor, university of California Cooperative Extension, Santa Rosa, California,
Vito Polito, Professor, Plant Science Dept., university of California, Davis, California
Source: Beede and Goldhamer, 2005
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Crop water use of mature olives (ETc) is determined by multiplying the refer-ence ETo by the olive crop coefficient (Kc) of 0.75 (Goldhamer, 1994). The resulting average water requirements of olive trees at full ETc can be met by a combination of rainfall and irrigation. Olive crop water use ETc in a clean cultivated orchard or where weeds are completely controlled is in table 1.
Increasing the amount of water applied past this amount showed little to no increase in yield (yield components in-cluding shoot growth, bloom, fruit size, fruit load, and oil content). Altering the Kc used in irrigation scheduling also did little to increase the value of the fruit, and thus the overall revenues collected). Goldhamer’s study showed that table olives perform best under these optimal conditions, but will survive extremely water-stressed conditions, as they are naturally drought tolerant trees.
OThER fACTORS AffECTING fuLL CROP wATER uSE Full ETc is reached once canopy cover exceeds 50% of the orchard surface. In young orchards with less than 50% canopy cover, crop water use will be reduced but not by the amount of the cover reduction. Increased reflection from the soil surface and advective heat from unshaded areas between rows increases young tree water use. If canopy cover is less than 50%, water use is estimated to be twice what the canopy cover percentage would sug-gest. For example, 10% cover would mean multiplying full ETc by 0.2 (or 20%), 30% cover means multiplying full ETc by 0.6.
IRRIGATION SChEDuLINGIf flood or sprinkler irrigation is used the soil water holding capacity must be
assessed to determine when to irrigate and how much water to apply. With low volume irrigation, drip emitters or micro-sprinklers are used to replace the water a tree uses daily or over two or three days. In this case, the water hold-ing capacity of the soil is less important and since a relatively small amount of water is being applied uniformly, deep percolation is usually not a concern.
Water application run time should be calculated by using the calculated daily ETc for the orchard, uniformity of the system, the application rate of the emitters, and the number of days since the last irrigation. Drip emitters or the wetted pattern should be at least two to three feet away from the tree to avoid crown rot. See the California Irrigation Management Information System website:www.cimis.water.ca.gov for additional information on optimum irrigation scheduling.
OPTIMuM OIL OLIvE IRRIGATIONIrrigation management has a profound influence on olive oil production and on olive oil quality but with some flexibility over a rather broad range below full ETc. Since the price received for olive oil is not related to fruit sizes oil olives can be irrigated less than table olives and still produce good olive oil.
A comparative study evaluating the in-fluence of seven different levels of water applied by drip irrigation to ‘Arbequina I-18’ olive trees grown in a super high density orchard (670 trees per acre) in the Sacramento Valley of California was conducted in the early 2000’s (Grattan et al, 2006). Full ETc was met in the Spring by annual rainfall and a fully recharged soil profile until the irrigation season began in late April to early May.
Jan Feb Mar April May June July Aug Sept Oct Nov Decinches/month 0.92 1.22 2.14 3.41 4.60 5.51 6.36 5.47 4.07 2.69 1.19 0.75gal/acre/day 801 1178 1872 3089 4027 4983 5571 4789 3686 2352 1079 657
inches/month 0.78 1.22 2.49 3.68 5.00 5.81 6.35 5.51 4.09 2.60 1.12 0.60gal/acre/day 683 1186 2181 3333 4375 5261 5564 4822 3700 2280 1011 526
Sacramento Valley
San Joaquin Valley
Olive Crop Water Use When Fully Irrigated
TAbLE 1. wATER uSE Of MATuRE OLIvES (ETC) whEN fuLLy IRRIGATED AND CLEAN CuLTIvATED.
Source: Beede and Goldhamer, 2005
“Increasing the amount of water applied past this amount showed
little to no increase in yield”
“Irrigation management has a profound influence
on olive oil production and
on olive oil quality”
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The reduced percentages of ETc applied were imposed during the irrigation season from roughly May to October at which time seasonal rainfall once again began to contribute to ETc demands in all treatments prior to harvest.
Similar to table olives, oil olive trees show reduced vegetative growth and have smaller fruit size as the percentage of ETc is reduced. Since oil olives are grown in hedgerows where small tree size must be maintained, once the trees are mature (filled their space), discour-aging excessively vigorous growth by controlling water is a desirable result. Fruits per branch, fruits per inflores-
First and second harvesty = -1E-07x 2 + 0.0005x + 0.125
R2 = 0.8705
y = -9E-08x 2 + 0.0004x + 0.2957R2 = 0.7051
0.0
0.2
0.4
0.6
0.8
1.0
0 500 1000 1500 2000 2500 3000 3500 4000
Irrigation water applied (L/tree)
Tota
l oil
(Kg/
tree)
fIGuRE 2. TOTAL OLIvE OIL PRODuCTION PER TREE IS OPTIMIzED ROuGhLy bETwEEN 40 AND 70% ETC.
Source: Grattan et al, 2006
cence, fruit density, and fruit set were all increased as applied water increased up to 71-89% ETc. Fruit retention was unaffected by irrigation treatment. Olive fruit weight increased as water applications increased with fruit yield approaching a maximum at about 71% ETc. Trees with higher irrigation levels were first to show color changes in fruit maturity but once fruits on water stressed trees began to mature they did so at a much faster rate.
The percentage of olive oil extracted from fruit decreased in a linear fashion at three of four harvest dates as the amount of applied water was increased.
ReferencesHartmann, H.T., Panetsos, C. 1961. Effect of soil moisture deficiency during floral development on fruitfulness in the olive.
Proc. Amer. Soc. Hort. Sci., 78: 209-217.
Goldhamer, D.A., J. Dunai, and L. Ferguson. 1994. Irrigation requirements of olive trees and responses to sustained deficit
irrigation. Acta Horticulturae 356: 172-176.
Beede, R. H. and D. A. Goldhamer. 2005. Olive irrigation management. In: Olive Production Manual, Second Edition, G. S.
Sibbett and L. Ferguson, eds. University of California Publication 3353. pp. 61-69.
Grattan, S.R., M.J. Berenguer, J.H. Connell, V.S. Polito and P.M. Vossen. 2006. Olive oil production as influenced by different
quantities of applied water. Agric. Water Mang. 85 (1-2): 133-140.
Berenguer, M.J., P.M. Vossen, S.R. Grattan, J.H. Connell, and V. S. Polito. 2006. Tree irrigation levels for optimum chemical
and sensory properties of olive oil. HortScience 41 (2): 427- 432.
The reduction in oil extraction with in-creased applied water is somewhat offset by increased fruit yield. Hence, total oil yield per tree reached a maximum at 70-75% ETc (Fig. 2) but is optimized over a rather broad range.
A companion study on oil quality mea-sured fruitiness, bitterness and pungen-cy of oils produced at various levels of water stress. Results showed that stress-ing olives to between 33 and 40% ETc produced oils that had a better balance of pungency and bitterness, were pleas-antly fruity, held both ripe and green character, had more complexity and depth, and boasted higher polyphenol content. High levels of irrigation lowered oil extractability and produced bland oils with significantly less fruitiness and almost no bitterness or pungency. Trees under the greatest water stress produced oils with excessive bitterness, very high pungency, and woody herbaceous fla-vors. Although all irrigation treatments produced oils of “extra virgin” quality, oil chemical and sensory characteristics indicate that intermediate irrigation (33-40% ETc) provided the best overall balance in oil quality (Berenguer et al, 2006).
Excellent olive oil yield can be achieved when in-season deficit irrigation is held at 70% ETc or a 30% reduction compared to full ETc. If water is supplied at 40% of ETc, olive oil quality is maintained but oil yield will begin to suffer. Based on oil olive irrigation research, optimum irrigation for producing olive oil ranges between the 33-40% ETc that maximizes olive oil quality and the 70-75% ETc that maximizes olive oil production. Therefore the optimal irrigation strategy depends on whether the objective is to optimize oil quantity or quality.
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NursTech, Inc. sponsored two two-day mini camps the first week of November, 2009. One day was spent at NursTech learning the fundamentals of our clean plant and mother block olive tree propa-gation system—the only one of its kind in North America. The second day focused on cultural practices with experts in the field, touring orchards and mills. Attendees from our distribution network now have access to the knowledge and experience that only NursTech, Inc. can offer.
For more information, contact Jeffers Richardson at NursTech, Inc. at (530) 846-0404.
NursTech mini-Camp attendees
NURSTECH
NEWS www.olint.com
a Grower’s Trip to ChileIn February of this year, 2009,
NursTech, Inc. led a group of eleven people, representing super high
density distributors, growers, olive oil processors, and consultants, to Chile to visit our “brethren” to the South. The trip offered a great opportunity to visit the different and diverse olive growing regions in Chile, from the arid north to the verdant fertile central valleys south of Santiago. It was universally noted by all what a beautiful country is Chile. What stood out among the group’s members were the different condi-tions in which the olives were grown, whether it was hilly terrain, rocky soil, or one with a high salinity. Impressive still was the shear size of some of the larger developments. I think everyone returned home with a good impression of what they saw, and an appreciation for the olive oil being produced.
NURSTECH
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NursTech, the world’s largest supplier of propa-gated olive plants, announced the addition of two new nurseries, Dave Wilson Nursery and Vintage Nursery, to its distribution network. This followed NursTech’s decision to replace two other distributors. This decision makes it easier for growers to obtain and plant new trees to meet the continued growth of California’s olive oil industry.
The new distributors are two of California’s most recognized nurseries, Dave Wilson Nursery, based in Hickman, and Vintage Nursery, based in Wasco. They will join well-known existing distributors Sierra Gold Nurseries, based in Yuba City, and Lodi Farming, based in Lodi, to provide an improved statewide network of distributors to better serve interested growers.
“We are thrilled to add these two highly-respected companies to our distribution network so that growers have easier access to our trees,” said Jeffers Richardson, NursTech’s Sales and Market-ing Manager. “All four distributors are known for their knowledgeable and experienced field staffs which add another layer of quality to the NursTech experience.”
NuRSTECh ANNOuNCES NEw DISTRIbuTORS
NEWS www.olint.com
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