icfr central regional interest group field day · andrea louw [email protected] institute...
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© ICFR 2009 Page 1 ICFR Central Regional Field Day
ICFR CENTRAL REGIONAL INTEREST GROUP FIELD DAY
Date: Thursday 28th May 2009
Venue: Fontana Church Hall, Piet Retief
Time: 08h00 for 08h30
PROGRAMMEPROGRAMMEPROGRAMMEPROGRAMME
08h00 Meet for tea and coffee at the Fontana Church Hall
INDOOR PRESENTATIONSINDOOR PRESENTATIONSINDOOR PRESENTATIONSINDOOR PRESENTATIONS
08h30 Welcome to the field day Rhudolf Muller &
Colin Dyer
Mondi
ICFR
08h40 Update on wattle pests and diseases Izette Greyling FABI
09h00 Genetic improvement in black wattle Andrea Louw ICFR
09h30 Interim results: current ICFR Acacia mearnsii spacing
trials Trevor Morley ICFR
10h00 TEA
10h20 Update on eucalypt pests and diseases Ryan Nadel FABI
10h40 Pulping properties of Eucalyptus benthamii and
improved Eucalyptus macarthurii. Tammy Swain ICFR
FIELD PRESENTATIONSFIELD PRESENTATIONSFIELD PRESENTATIONSFIELD PRESENTATIONS
11h10 Travel to first field stop
11h30
Research to investigate the impact of planting depth,
seedling size and planting method on eucalypts in
summer rainfall region of South Africa
Paul Viero Mondi
12h15 Travel to second field stop (Mr G Stapelberg, Welgekozen)
12h45 In-field discussions on wattle and eucalypt pests and
diseases
Izette Greyling &
Ryan Nadel FABI
13h15 Presentation and discussion on a land preparation
operation, including site preparation and mulching G Stapelberg Private
13h45 LUNCH at the Fontana Hall, Piet Retief
© ICFR 2009 Page 2 ICFR Central Regional Field Day
UpdateUpdateUpdateUpdate on wattle pests and diseases on wattle pests and diseases on wattle pests and diseases on wattle pests and diseases
Izette Greyling [email protected]
Tree Protection Co-operative Programme (TPCP), University of Pretoria, Pretoria, South Africa
DiseasesDiseasesDiseasesDiseases •••••••• Ceratocystis wilt – Ceratocystis albifundus
•••••••• Botryosphaeria canker and wilt – Botryoshaeria species
•••••••• Phytopthora root rot – Phytopthora nicotianeae
•••••••• Pink disease – Erythricium salmonicolor
•••••••• Cylindrocladium blight/canker – Cylindrocladium pauciramosum – Nursery & Recent
Transplants
PestsPestsPestsPests •••••••• Bagworm – Chaliopsis junodi
•••••••• Mirid – Lygidolon laevigatum
•••••••• Termites
•••••••• Cutworm
•••••••• White grub
TREEHEALTHNETTREEHEALTHNETTREEHEALTHNETTREEHEALTHNET
An online forum where tree health issues are discussedAn online forum where tree health issues are discussedAn online forum where tree health issues are discussedAn online forum where tree health issues are discussed The TREEHEALTHNET listserver was established to enable fast and effective communication
between scientific and technical staff linked to the Tree Protection Co-operative Programme
(TPCP), the DST/ NRF Centre of Excellence in Tree Health Biotechnology (CTHB), and staff of the
TPCP member-companies. News related to tree health, feedback about current research efforts
and field work, as well as important announcements are circulated among subscribers to this
listserver. Field trips are announced in advance, enabling foresters, forest managers and other
stakeholders to request visits from the TPCP and CTHB researchers.
At present the TREEHEALTHNET listserver reaches about 120 subscribers, mainly staff of South
African forestry companies. Most are decision-makers or research staff of companies. Given the
increasing pressure on forestry and forests due to pests and diseases, we would all benefit from the
listserver reaching a broader community, including forestry staff at grassroots level. If you wish to
subscribe or you wish to have your staff/ colleagues participating, just send an e-mail to the list
manager, Wilhelm de Beer, at [email protected]. The listserver is SPAM secure and
we will make every effort not to overburden subscribers. It is also open only to those who have
subscribed and it is possible to unsubscribe as easily as one subscribes to the list.
© ICFR 2009 Page 3 ICFR Central Regional Field Day
Genetic improvementGenetic improvementGenetic improvementGenetic improvement in black wattle ( in black wattle ( in black wattle ( in black wattle (Acacia mearnsiiAcacia mearnsiiAcacia mearnsiiAcacia mearnsii))))
Andrea Louw [email protected]
Institute for Commercial Forestry Research, PO Box 100281, Scottsville 3209
IntroductionIntroductionIntroductionIntroduction In the past, the driving force behind the black wattle industry was bark yield, as the bark has a high
tannin content and is economically valuable. Tannin-based products are produced for both tanning
and non-tanning applications. Currently, there is a very high export demand for bark.
Apart from the commercial value of its bark, black wattle timber has, in recent years, become
popular as a source of high quality fibre for pulp and paper production. Subsequently, market
demands for black wattle changed from tannin to wood, and today, timber has taken the leading
role in the industry. However, an acceptable bark quality is still maintained. Today, black wattle
makes up approximately 8.1% of the South African plantation forestry estate, an area of about
103 000 ha.
Black Wattle ImprovementBlack Wattle ImprovementBlack Wattle ImprovementBlack Wattle Improvement Black wattle was introduced into South Africa from Australia in 1864 for use in commercial
plantations. Through adaptation to different environmental sites and climatic conditions, this
material became what is now known as the South African landraces, and this is what constitutes
South Africa’s current commercial plantations.
When the first black wattle breeding programmes were implemented, seed was collected from
specific families in Australia as well as from the South African commercial plantations, and
research trials were established (Figure 1Figure 1Figure 1Figure 1). From measurements and assessments of the research
trials, the best families and individuals were identified and selected, based on specific
characteristics, such as bark quality, timber yield, cold tolerance and disease tolerance. Seed was
collected from these individuals and further research trials were established. In these trials, the
process was repeated, and further improved seed orchards established. These seed orchards are
now swept and the improved seed supplied to the industry. Companies purchase the improved seed
as seedlings from nurseries, and by purchasing these seedlings they achieve the gains or
improvement made through the breeding strategy.
Figure Figure Figure Figure 1111.... Wattle Improvement at the ICFR
Wattle improvement at the ICFR
SA (Landraces)
Australia
Research trialsCold toleranceTimber yieldBark qualityDisease free
Trials
Best individuals identified
Improved seed
supplied to the industry
Superior trees
Seed Orchards
Seedlings
swept
GAIN
Wattle improvement at the ICFR
SA (Landraces)
Australia
Research trialsCold toleranceTimber yieldBark qualityDisease free
Trials
Best individuals identified
Improved seed
supplied to the industry
Superior trees
Seed Orchards
Seedlings
swept
GAIN
© ICFR 2009 Page 4 ICFR Central Regional Field Day
Genetic gain trialsGenetic gain trialsGenetic gain trialsGenetic gain trials In any improvement programme, it is essential that the available improved material is tested
against the unimproved material to assess that improvement is in fact occurring. This is successfully
achieved by planting genetic gain trials. The unimproved seed, used as a control in the research
trials, acts as a baseline in order to determine the degree of improvement made. Currently, in the
wattle breeding programme, genetic gain trials are being used to estimate the performance of the
older seed orchards (established in the early 1970s and ‘80s) relative to the newer seed orchards
(established from the mid 1990s). An expected increase in volume has been estimated from some
of the orchards, which equates to an increased MAI.
Genetic gain trials are of particular importance to the wattle growers using seedlings, in indicating
that the material that they are planting will produce higher yields.
Future Seed OrchardsFuture Seed OrchardsFuture Seed OrchardsFuture Seed Orchards In addition to the current seed orchards supplying the industry with improved seed, a new strategy
was implemented in the wattle breeding programme in 2002, to produce future seed orchards.
These seed orchards will produce individuals with increased volume, whilst still maintaining an
acceptable bark quality, as well as ensuring the continued improvement of the species and the
adequate supply of improved seed to the industry. Figure 2Figure 2Figure 2Figure 2 illustrates these gains (percentage
improvement) in diameter at breast height. Half-rotation measurements show the percentage
improvement of each subpopulation relative to i) the unimproved Natal Tanning Extract (NTE)
material, and ii) one of the older seed orchards (PSOs), currently supplying the industry with
improved seed, when selecting the best families in the population to contribute to improved seed
production. Estimated gains from the new breeding strategy subpopulations ranged from 12.4 to
29.0% increase in dbh (relative to NTE) and from 2.1 to 24.7% (relative to the PSO).
Figure Figure Figure Figure 2222. . . . Percentage improvement in dbh of the top families in the subpopulations relative to unimproved
(NTE) and improved (PSO) material.
0 10 20 30
1
2
3
4
5NTE
PSO
Percentage Improvement in dbh
Su
bp
op
ula
tio
n
© ICFR 2009 Page 5 ICFR Central Regional Field Day
Take home pointsTake home pointsTake home pointsTake home points � Results show that the subpopulations, currently representing the main breeding population of
A. mearnsii at the ICFR are performing better than NTE (unimproved seed) and the PSO
material (improved seed).
� Selection would provide potential for further improvement and substantial genetic gains, which will benefit the growers using the seed emanating from this breeding programme.
� Individual selection of superior trees should provide greater gains than family selection. � Growers should always try to obtain the most advanced generation of genetic material for plantation establishment.
© ICFR 2009 Page 6 ICFR Central Regional Field Day
Interim results:Interim results:Interim results:Interim results: CCCCurrent ICFR urrent ICFR urrent ICFR urrent ICFR Acacia mearnsiiAcacia mearnsiiAcacia mearnsiiAcacia mearnsii spacing trials spacing trials spacing trials spacing trials
Trevor Morley [email protected]
Institute for Commercial Forestry Research, P O Box 100281, Scottsville, 3209
SummarySummarySummarySummary
IntroductionIntroductionIntroductionIntroduction Since 1948, WRI/ICFR1 research on Acacia mearnsii (black wattle) planting densities reported
primarily on the line sowing method of establishment with subsequent thinning treatments. During
the last two decades, research on genetic improvement and silvicultural practices has led to the
current recommendation that wattle stands be established from seedlings rather than the
traditional methods of line sowing or natural regeneration. While this allows growers to benefit from
the superior genetic quality of the seedlings, the need for the current practice of planting at a
higher density, followed by thinning operations, has been questioned. To address this, an ICFR
spacing trial series was initiated in 2000/1 using improved A. mearnsii seedlings to compare the
effect of planting density (with no thinning) on the rate of growth, survival, form and productivity at
various sites.
MethodsMethodsMethodsMethods • Three trial sites contrasting in rainfall and temperature were selected at Highflats, Luneburg
and Pietermaritzburg.
• Each trial comprises six treatments, replicated twice, laid out in a randomised blocks
design.
• Plots comprise 144 trees (12 x 12 trees) with the inner 64 trees (8 x 8 trees) measured.
• Plot areas vary according to between- and within-row treatment distance for planting
densities of 1111, 1333, 1667, 1905, 2222 and 2500 trees ha-1.
• Dbh and tree height have been measured annually since establishment, with percentage
mortality and basal area calculated by deduction.
• Trial data were summarised, at approximately age 5 years.
• Site and cross site analyses of variance (ANOVA) were conducted on plot mortality,
quadratic mean dbh (Dq) and height (Hq), and basal area (BA).
• Utilisable volume was estimated to a 5 cm underbark topend diameter.
ResultsResultsResultsResults At approximately five years of age, the trials showed:
Mortality: Mortality: Mortality: Mortality:
No significant differences were detected for mortality between the different treatments at any of
the sites. Bloemendal and Luneburg (15.8 and 13.7%) had higher mortality than Highflats
(10.5%). There are no clear treatment-related trends in terms of mortality within each site, or
between sites, indicating that at this stage mortality may be related to factors other than those
of planting density (eg. windthrow). It is expected that as the trees age, an increase in mortality
will occur in the higher density treatments.
Hq: Hq: Hq: Hq:
This was taller for the lower density treatments at all three trials with treatment differences
significant only at Highflats. Hq is approximately 93% of dominant height at Bloemendal, 95%
at Highflats and 93% at Luneburg.
Dq: Dq: Dq: Dq:
There were significant differences at all three trials in terms of Dq with the lower density
treatments (1111 and 1333 sph) being larger than the higher density treatments (2222 and
2500 sph).
1 Wattle Research Institute (WRI)/ Institute for Commercial Forestry Research (ICFR)
© ICFR 2009 Page 7 ICFR Central Regional Field Day
BA: BA: BA: BA:
Similar to Dq and Hq results, there were treatment related differences in BA (which is a
function of stem area and survival), although these were significant only at Highflats and
Luneburg (Table 3 and Figure 1).
Across site analyses showed significant (p < 0.05) site related differences for Ht and Dbh, but not
for mortality, whereas BA was only weakly significant (p < 0.1). No significant interactions were
detected between the three sites and the various treatments, indicating that at this stage treatments
are showing similar trends in terms of the measured growth parameters. Dbh and height was best
at Luneburg and the lower mortality at Highflats gave the highest overall BA treatment (16.95 m2
ha-1 for 2500 sph) (Table 1Table 1Table 1Table 1 and Figure 1Figure 1Figure 1Figure 1). Bloemendal had the lowest average BA (range 9.4 –
12.8 m2 ha-1). Treatment density effects on BA were more apparent at Highflats (larger treatment
differences) than at Luneburg (smaller differences). Growth differences between treatments were
least at Bloemendal whereas statistically significant differences between treatments were
pronounced at Luneburg and especially Highflats (Table 1Table 1Table 1Table 1 and Figure 1Figure 1Figure 1Figure 1). The utilisable volume of
the current stocking densities at about age 5 years, for the sites is illustrated by logarithmic trend
lines in Figure 1Figure 1Figure 1Figure 1.
Figure 1Figure 1Figure 1Figure 1 (top) (top) (top) (top) Development of basal area (m2 ha-1) over time for the Luneburg Acacia mearnsii spacing
trial.
(bottom) (bottom) (bottom) (bottom) Effect of stocking (TPH) on utilisable volume (UVolume) across trial sites.
0
20
40
60
80
100
120
900 1100 1300 1500 1700 1900 2100 2300 2500
TPH at about 5 years
UV
OL
UM
E (
m3 h
a-1)
Luneburg
Highflats
Bloemendal
0
2
4
6
8
10
12
14
16
18
2 3 4 5
Age (Years)
BA
(m
2 h
a-1
)
1111
1333
1667
1905
2222
2500
25001667
1905
11111333
2222
Table 1.Table 1.Table 1.Table 1. Summary of analyses of variance showing the mean squares and treatment means, within sites at approximately five years of age, for three Acacia mearnsii
spacing trials in the summer rainfall region of South Africa.
Site and age (years)Site and age (years)Site and age (years)Site and age (years) Bloemendal Bloemendal Bloemendal Bloemendal (5.007) HighflatsHighflatsHighflatsHighflats (4.941) LuneburgLuneburgLuneburgLuneburg (5.037)
Source of variationSource of variationSource of variationSource of variation d.fd.fd.fd.f HqHqHqHq
(m)(m)(m)(m)
DqDqDqDq
(cm)(cm)(cm)(cm)
MortalityMortalityMortalityMortality####
(%)(%)(%)(%)
BABABABA
(m(m(m(m2222 ha ha ha ha----1111))))
HqHqHqHq
(m)(m)(m)(m)
DqDqDqDq
(cm)(cm)(cm)(cm)
MortalityMortalityMortalityMortality####
(%)(%)(%)(%)
BABABABA
(m(m(m(m2222 ha ha ha ha----1111))))
HqHqHqHq
(m)(m)(m)(m)
DqDqDqDq
(cm)(cm)(cm)(cm)
MortalityMortalityMortalityMortality####
(%)(%)(%)(%)
BABABABA
(m(m(m(m2222 ha ha ha ha----1111))))
Rep 1 0.23 0.52 0.26 4.2 1.42 0.04 0.58 0.42 0.01 0.01 1.28 4.45
Treatments 5 0.36ns 2.13* 0.72ns 3.2ns 0.62* 2.83** 0.60ns 7.54** 0.28ns 2.89** 0.30ns 3.44**
Residual 5 0.77 0.28 0.71 1.5 0.08 0.02 0.18 0.37 0.22 0.5 0.19 0.18
Total 11
Summary of dataSummary of dataSummary of dataSummary of data
(Treatment means)(Treatment means)(Treatment means)(Treatment means)
1. 1111 13.17 11.48a 4.19 (18.0) 9.43 15.05ab 12.20a 4.5 (11.7) 11.46a 15.46 13.21a 4.96 (15.6) 12.85a
2. 1333 13.27 10.99ab 3.18 (10.2) 11.41 15.67a 12.30a 5.4 (20.3) 12.63a 15.40 11.61b 4.19 (8.6) 12.94a
3. 1667 13.57 10.83ab 4.33 (18.8) 12.48 14.76bc 10.96b 4.1 (7.8) 14.49b 15.82 11.42b 4.33 (10.2) 15.35bc
4. 1905 12.90 9.78bc 3.75 (14.1) 12.30 14.67bc 10.50b 4.2 (8.6) 15.08b 14.83 10.72c 4.85 (14.8) 14.62b
5. 2222 12.56 9.09c 3.25 (11.7) 12.76 14.33bc 9.66c 4.1 (8.6) 14.89b 15.08 10.10d 4.85 (14.8) 15.14bc
6. 2500 12.46 9.08c 4.65 (21.9) 12.60 14.09c 9.60c 3.9 (6.2) 16.95c 14.93 9.97d 5.19 (18.0) 16.01c
Grand Mean 12.99 10.21 3.89 (15.8) 11.83 14.76 10.87 4.38 (10.5) 14.25 15.25 11.17 4.73 (13.7) 14.49
Std. error of the difference 0.88 0.53 0.84 (6.31) 1.20 0.29 0.16 0.42 (3.48) 0.61 0.47 0.22 0.44 (4.10) 0.43
CV (%) 6.8 5.2 21.6 (40.0) 10.2 2.0 1.4 9.6 (33.0) 4.3 1.2 2.0 9.2 (30.0) 3.0
NoteNoteNoteNotessss:::: * and ** denote significance at p < 0.05 (F5,5 5.05) and p < 0.01 (F5,5 10.97) respectively and ns denotes non-significance.
Within each column, values followed by the same letter are not significantly different (p < 0.05) according to Student’s t-test. # Square root transformation carried out on Mortality data. Percentage (untransformed means) values are shown in brackets for the readers benefit.
© ICFR 2009 Page 9 ICFR Central Regional Field Day
Take Take Take Take hhhhome ome ome ome pointspointspointspoints � Mid-rotation results show initial stand density does not have a substantial effect on the growth of Acacia mearnsii.
� Although volume increased at Highflats and Luneburg with increasing stocking, the difference in doubling the current stocking from 1100 to 2200 TPH was less than 21 m3 ha-1.
� Best growth on the Bloemendal lower productivity site was between 1400 and 1600 TPH but the difference between best and worst stocking was not substantial (6 m3 ha-1).
� Results suggest planting at higher densities (>1800 TPH) without thinning does not necessarily result in consistently better growth.
� The grower will also need to determine whether any increase in volume associated with the higher stand densities offsets initial establishment and harvesting costs, compared to the
lower density treatments.
© ICFR 2009 Page 10 ICFR Central Regional Field Day
PPPPulping propulping propulping propulping properties of erties of erties of erties of Eucalyptus benthamiiEucalyptus benthamiiEucalyptus benthamiiEucalyptus benthamii and and and and
improvedimprovedimprovedimproved Eucalyptus macarthuriiEucalyptus macarthuriiEucalyptus macarthuriiEucalyptus macarthurii
Tammy Swain
[email protected] Institute for Commercial Forestry Research, P O Box 100281, Scottsville, 3209
SummarySummarySummarySummary
Eucalyptus macarthuriiEucalyptus macarthuriiEucalyptus macarthuriiEucalyptus macarthurii Eucalyptus macarthurii is the most frost tolerant of the cold tolerant eucalypts grown commercially
in South Africa, and is often the only eucalypt species that will grow on certain temperate sites.
Tremendous gains have been made in the two generations of breeding that have been completed
by the ICFR - these include increases in growth/yield and improvement in stem form, bark
strippability and snow tolerance.
It has been found that genotype by environment interaction (GEI) exists in the ICFR
E. macarthurii breeding population for various growth characteristics, meaning that certain families
are strongly influenced by environment, and perform better at one site type than at another. The
presence of GEI also indicates that different breeding populations should be developed
independently of each other for different sites.
Pulping studies have indicated that E. macarthurii does not have as favourable pulp yields as
species such as E. smithii and E. nitens. A project was undertaken to select for improved pulp yield
in ICFR’s improved 2nd generation breeding population. Core samples at breast height were taken
of almost 600 selected trees in sub-populations and progeny trials in both KwaZulu-Natal and
Mpumalanga. These cores were then ground into sawdust and scanned using Near Infra Red (NIR)
spectroscopy, using a model developed for this purpose (Ndlovu, 2009).
ResultsResultsResultsResults Total Pulp Yield (TPY) percentages were predicted using NIR for selected trees in the 2nd
generation breeding population. Total Pulp Yield is the percentage Screened Pulp Yield of the
sample plus the rejects, and provides values which can be used for relative ranking of individuals,
rather than absolute pulp yields. This is still very useful in a Tree Improvement programme, where
top individuals can be selected based on ranking. The TPY’s showed the following:
• TPY differed significantly (p ≤ 0.001) according to whether the trees were grown in
KwaZulu-Natal or Mpumalanga i.e. South African provinces influence TPY. In this case,
TPYs were higher in KwaZulu-Natal than in Mpumalanga.
• Within both KwaZulu-Natal and Mpumalanga provinces, there were significant site
differences (p ≤ 0.001) with regards to TPY. However, in both provinces, generally two sites
contributed significantly to this difference ie. in KwaZulu-Natal, sites at Maxwell and
Pinewoods differed from the rest, and in Mpumalanga, sites at The Brook and Dorstbult
differed.
• The 2nd generation families differed significantly (p ≤ 0.001) from each other for TPY. This
indicates that it is possible to select families for improved pulp yield.
© ICFR 2009 Page 11 ICFR Central Regional Field Day
Eucalyptus benthamiiEucalyptus benthamiiEucalyptus benthamiiEucalyptus benthamii Due to the many factors affecting growth of some cold tolerant eucalypt species on high altitude,
temperate forestry sites, there was a need to investigate alternate eucalypt species for the
temperate areas. ICFR site-species interaction trials established during the late 1980s and early
1990s showed that E. benthamii was one of the few species which showed commercial potential in
these areas. Tree improvement trials testing a wider range of Australian E. benthamii seedlots and
provenances were established at three sites in South Africa, and showed that provenance
differences exist for growth in this species (Swain and Gardner, 2003), as well as confirming the
potential role of E. benthamii in the South African forestry industry.
Very little is known about the pulping properties of this species, other than the results obtained by
Gardner (2001) from limited samples in two ICFR site–species trials, with no provenance
representation. To gain further knowledge of the pulp yields in this species, wood samples of three
bulked E. benthamii provenances were collected from two of the ICFR provenance progeny trials at
Panbult (Iswepe, Mpumalanga) and Mossbank (Bulwer, KwaZulu-Natal) (see Table 1Table 1Table 1Table 1 for site
details) and pulped by the CSIR for Total Pulp Yield (TPY).
Table 1. Table 1. Table 1. Table 1. Site details of E. benthamii provenance/progeny trials from which wood samples were
collected.
LocalityLocalityLocalityLocality
LatitudeLatitudeLatitudeLatitude
(S)(S)(S)(S)
LongitudeLongitudeLongitudeLongitude
(E)(E)(E)(E)
AltitudeAltitudeAltitudeAltitude
(m)(m)(m)(m)
MAPMAPMAPMAP
(mm)(mm)(mm)(mm)
MATMATMATMAT
((((ooooC)C)C)C)
Soil depthSoil depthSoil depthSoil depth
(mm)(mm)(mm)(mm) Mossbank, Bulwer
29o50'
29o42'
1610
1050
14.4
1200
Leiden, Panbult
26o50'
30o18'
1470
800
15.0
>1200
ResultsResultsResultsResults The TPYs obtained from the E. benthamii and control species wood samples at two sites showed
(Figure 1Figure 1Figure 1Figure 1):
• Site differences were apparent, as with the E. macarthurii study. Total Pulp Yields at the
wetter Mossbank site were higher than at Panbult.
• Of the three E. benthamii provenances that were sampled, the Bents Basin material
produced lower TPYs than Kedumba Valley A and B at both sites. Interestingly, this was the
same trend that was found with the dbh measurements in these trials (Swain and Gardner,
2001).
• E. nitens had the highest TPY of all species at Mossbank, followed by E. benthamii
Kedumba Valley A and E. badjensis. The E. benthamii Kedumba Valley A provenance had
a higher TPY than E. macarthurii.
This indicates that E. benthamii may be a suitable alternative to E. macarthurii in terms of
pulp yield, and that variation does exist in the new species to improve pulp yield even
further.
© ICFR 2009 Page 12 ICFR Central Regional Field Day
FFFFigure 1. igure 1. igure 1. igure 1. Screened and Total pulp yields (%) of three bulked E. benthamii provenances and controls, at
two different sites.
Take Take Take Take hhhhome ome ome ome ppppoints:oints:oints:oints:
� Improved E. macarthurii families differ significantly from each other for Total Pulp Yield.
� It is therefore possible to select certain E. macarthurii families and individuals which are
already superior in terms of growth and stem form, and to further improve them with
regards to pulp yield.
� However, as genotype by environment interactions exist for growth characteristics as well as pulp yield, it is suggested that two separate populations of E. macarthurii are bred for
commercial deployment in KwaZulu-Natal and Mpumalanga.
� Provenance differences exist for pulp yield in E. benthamii.
� On the one site sampled, the Kedumba Valley A provenance of E. benthamii outperformed
E. macarthurii for Total Pulp Yield.
� Therefore E. benthamii may be a suitable alternative to E. macarthurii in terms of pulp yield
on certain sites.
ReferencesReferencesReferencesReferences Gardner, RAW. 2001. Site-species interaction studies with cold-tolerant eucalypts in South Africa: Final
results of a 1990/1991 - planted high-altitude series. In: Proceedings of IUFRO Working
Group 2.08.03 Conference “Developing the eucalypt of the future”, Valdivia, Chile, 10-14
September, 2001.
Ndlovu, ZTL. 2009. Breeding of advanced generation Eucalyptus macarthurii - growth parameters and
development of a near infrared (NIR) calibration model to predict whole tree pulp yield using
non-destructive cores. MSc thesis. University of KwaZulu-Natal.
Swain, T-L and Gardner, RAW. 2001. New cold tolerant eucalypt species in South Africa – an update on
provenance/progeny trials on E. badjensis and E. benthamii. In: Proceedings of IUFRO
Working Group 2.08.03 Conference “Developing the eucalypt of the future”, Valdivia, Chile,
10-14 September, 2001.
Swain, T-L and Gardner, RAW. 2003. A summary of current knowledge of cold tolerant eucalypt species
(CTE’s) grown in South Africa. ICFR Bulletin Series 03/2003. Institute for Commercial
Forestry Research, Pietermaritzburg, South Africa.
0
10
20
30
40
50
60
Pulp
yie
ld (%
)
E. nitens
E. ben - K
A
E. badje
nsis
E. m
acarthurii
E. dorrig
oensis
E. ben - K
B
Ben - B
B
E. ben - K
B
E. ben - K
A
E. ben - B
B
Mossbank Panbult
% Screened Pulp yield
% Total Pulp Yield
E. benthamiiE. benthamiiE. benthamiiE. benthamii provenances: provenances: provenances: provenances:
KA – Kedumba Valley A
KB – Kedumba Valley B
BB – Bents Basin
© ICFR 2009 Page 13 ICFR Central Regional Field Day
Research to investigate the impact of seedling size, planting depth and Research to investigate the impact of seedling size, planting depth and Research to investigate the impact of seedling size, planting depth and Research to investigate the impact of seedling size, planting depth and
planting method on eucalypts in the summer rainfall region of South Africaplanting method on eucalypts in the summer rainfall region of South Africaplanting method on eucalypts in the summer rainfall region of South Africaplanting method on eucalypts in the summer rainfall region of South Africa (a trial series by the ICFR)(a trial series by the ICFR)(a trial series by the ICFR)(a trial series by the ICFR)
Paul Viero [email protected]
Mondi Limited. P O Box 39, Pietermaritzburg 3200
Introduction:Introduction:Introduction:Introduction: The commercial planting of eucalypts in South Africa will typically include operations such as
marking, pit preparation, planting and watering, all of which may impact on the successful re-
establishment of eucalypts. For each of these operations there are a number of factors that vary
according to geographic region, company policy and individual contractor understanding.
Examples of this include the choice of pitting instrument (hoe, pick or mechanical pitting head); pit
dimensions (depth and width, usually a function of the choice of implement and company
specifications), method of planting and size of the plants used (robustness/sturdiness). Some
companies advocate a “no water” planting policy, others will always plant with water, or will
schedule watering only at times when planting conditions are considered poor (i.e. hot and dry
conditions). Numerous trials worldwide have indicated that larger seedlings (in terms of root collar
diameter and root-plug volume) will survive better than smaller seedlings, thus the impact of
seedling size also needs to be determined for various methods of regeneration, including the depth
at which seedlings are planted, and whether water is used in the process or not.
Most forestry companies in South Africa will agree that the placing of the root plug deeper when
planting (as opposed to shallow) is beneficial to initial seedling/plant survival and growth. However,
the depth at which one is able to plant will often be determined by the size of the seedling that is to
be used with differences based primarily on morphology and age. With a wide range of planting
practices and plant qualities in use across the many land holdings in South Africa, it is often
difficult to understand the function of these different methods as well as to determine which
combination of operations is effective and which is not.
To address these questions the Regeneration Research Project of the ICFR has implemented a
series of three trials focused on increasing understanding of how seedling size (as determined by
root plug volume), planting depth (normal and deeper planting methods) and planting method
(water versus dry planting) will affect survival and early growth in eucalypts. The trials were
implemented in three different physiographic/climatic regions, using species best matched to each
site.
Trial design and treatmentsTrial design and treatmentsTrial design and treatmentsTrial design and treatments • The trial is a 2 x 2 x 2 factorial with one additional control, all of which were replicated four
times. The additional control was duplicated twice within each replicate = total of 10
treatment plots x 4 reps = 40 plots in total.
• Each treatment plot will consist of 8 rows and 8 trees within each row = 64 trees per plot.
• Only the inner 6 x 6 trees will be measured.
• Details for the treatment factors and levels, and their motivation, are given in Tables 1Tables 1Tables 1Tables 1 and
2.2.2.2.
© ICFR 2009 Page 14 ICFR Central Regional Field Day
Table 1. Table 1. Table 1. Table 1. Description of the treatment factors and levels, and additional controls, to be implemented for the
proposed trial series
FactorFactorFactorFactor LevelLevelLevelLevel DescriptionDescriptionDescriptionDescription QuestionQuestionQuestionQuestion
Standard 128 cavity tray = 36 cm3
cavity-1
Size of root plugSize of root plugSize of root plugSize of root plug
(Seedling size)
Large 72 cavity tray = 103 cm3
cavity-1
Can early plant survival and growth be
enhanced through using plug volume,
with a corresponding increase in
seedling size?
Standard Top of root plug 5cm below
soil surface.
Depth of planting Depth of planting Depth of planting Depth of planting
Deep Top of root plug 15cm below
soil surface
Compared to the standard depth of
planting, does planting deeper
significantly enhance plant survival and
initial growth (root plug in cooler,
moister zone)? Is planting depth a
function of plant size?
Dry plant No water used in the
planting operation Method of plantingMethod of plantingMethod of plantingMethod of planting
Water plant One litre water applied prior
to planting
Does planting with water significantly
improve survival over that of dry
planting? Is there an interaction with
seedling size and depth of planting?
Additional controlAdditional controlAdditional controlAdditional control
Hydrogel Optimum rate of Hydrogel
applied to planting hole.
Does a hydrogel provide for better
survival over dry or water planting?
Table 2. List of treatments.Table 2. List of treatments.Table 2. List of treatments.Table 2. List of treatments.
Treatment Treatment Treatment Treatment
NoNoNoNo Plug sizePlug sizePlug sizePlug size
Depth of Depth of Depth of Depth of
plantingplantingplantingplanting
Method of Method of Method of Method of
plantingplantingplantingplanting
Additional Additional Additional Additional
ControlsControlsControlsControls
1 Standard Standard Dry -
2 Standard Standard Water -
3 Standard Deeper Dry -
4 Standard Deeper Water -
5 Large Standard Dry -
6 Large Standard Water -
7 Large Deeper Dry -
8 Large Deeper Water -
9 Standard Standard - Hydrogel
10 Standard Standard - Hydrogel
Take home pointsTake home pointsTake home pointsTake home points::::
This trial series has been implemented to help further understanding as to the impact that various
selected re-establishment practices may have on plant survival and growth (initial and at rotation
end).
These re-establishment practices include the following:
� Plant quality, looking at two different plant sizes based on different size plug volumes,
namely:
� a standard plug derived from a 128 deep cavity tray and
� a large plug derived from a 72 cavity tray,
� Different planting depths (standard versus deeper plantings),
� Different planting methods (with or without water), and
� The interaction (if any) between plant size, planting depth and method of planting.
© ICFR 2009 Page 15 ICFR Central Regional Field Day
Update on eucalypts pestsUpdate on eucalypts pestsUpdate on eucalypts pestsUpdate on eucalypts pests; ; ; ; Leptocybe invasa, Thaumastocoris peregrinus and Gonipterus scutellatusLeptocybe invasa, Thaumastocoris peregrinus and Gonipterus scutellatusLeptocybe invasa, Thaumastocoris peregrinus and Gonipterus scutellatusLeptocybe invasa, Thaumastocoris peregrinus and Gonipterus scutellatus
Ryan Nadel [email protected]; 012 420 3938/9
Tree Protection Co-operative Programme (TPCP), University of Pretoria, Pretoria, South Africa
SummarySummarySummarySummary
Leptocybe invasaLeptocybe invasaLeptocybe invasaLeptocybe invasa In 2007 the Eucalyptus gall wasp, Leptocybe invasa, was found in the Pretoria area. The discovery
was made by Dr. Stefan Neser in June 2007 during his regular insect surveys on Eucalyptus in the
area. At that point, the wasp was only known from a few trees in a limited area. Follow-up surveys
later in 2007 by members of the TPCP have found galls on Eucalyptus plants a few kilometres
away, showing that the introduction must have happened well before June 2007 and was
spreading.
Leptocybe has spread incredibly fast throughout other countries where it was introduced, and this
seems to indeed also be the case in South Africa. Early in 2008 the first infestations were noticed in
the FABI nursery at the University of Pretoria experimental farm, some distance from the initial
detection sites. Subsequently, infested plants have also been found in more than one location
around Johannesburg. Heavily infested Eucalyptus was also recently discovered in the Brits area by
members of the Plant Protection Research Institute (PPRI) and even in the Upington area! More
recently this year heavily infected trees was found outside Bela Bela (Warmbad) and Nylstroom in
the Limpopo Province.
It is of utmost importance that every forester assists to monitor the spread of the Eucalyptus gall
wasp. This is especially important for NURSERY MANAGERS. Sending infested plants to the field is
one of the fastest routes to spread this damaging wasp. Please note the photographs below with
typical galls or swellings on the midrib of the leaves, or young twigs. More images are available on
the TPCP website (www.fabinet.up.ac.za/tpcp).
If you suspect that you have the Eucalyptus gall wasp, please contact us to organise a visit to the
site, or send a picture of the observed symptoms. Do not package and send these galls to us. The
wasps are very small and could easily escape from packaged material and spread to new areas.
© ICFR 2009 Page 16 ICFR Central Regional Field Day
Thaumastocoris peregrinusThaumastocoris peregrinusThaumastocoris peregrinusThaumastocoris peregrinus Thaumastocoris peregrinus is a serious pest in all Eucalyptus growing regions of South Africa.
Intensive countrywide surveys of this pest have revealed that 26 Eucalyptus species, including three
commercial hybrids, are susceptible to infestation by T. peregrinus. In addition the difficulty in
accurately determining the size of the populations involved in infestation progression or reduction
was revealed.
A monitoring trial to elucidate the effects of a range of environmental variables on
T. peregrinus populations was established in February 2007. Six trial sites were established, located
across northern and eastern parts of South Africa, representing different Eucalyptus growing and
climatic regions. At each site, yellow sticky traps were monitored and changed weekly and together
with daily measurements of temperature, humidity and rainfall.
Populations fluctuated greatly over the study period, revealing unique patterns of build-up and
decline at the various sites. Both temperature and humidity were found to affect the population
dynamics of T. peregrinus at the test sites. Data emerging from this trial will now be used to
develop population models and to direct control strategies such as biological control that appears
to be the only viable option to manage this pest.
Gonipterus scutellatusGonipterus scutellatusGonipterus scutellatusGonipterus scutellatus The Eucalyptus Snout Beetle, Gonipterus scutellatus, is a defoliator of Eucalyptus trees, often
resulting in severe damage. Originating in Australia, G. scutellatus was first recorded in South
Africa in 1916, in Newlands, Cape Town. Gonipterus scutellatus spread rapidly and by 1929 was
present in the majority of South Africa’s Eucalyptus growing areas. The spread of Gonipterus is also
evident on a global scale, as it has spread to every continent, except Antarctica.
In 1926 the egg parasitoid, Anaphes nitens, was introduced from Australia into South Africa as a
biological control agent for G. scutellatus. This wasp was highly successful in controlling G.
scutellatus in the low altitude sites. However, higher altitude, marginal sites still experience
outbreaks of G. scutellatus, often resulting in considerable damage. The cold and dry winters of
these sites are thought to hinder the activity of the wasp. Chemicals are often used to control
outbreaks of G. scutellatus. Although temporary control may be established, chemical control
should be used with caution, as the biological control agent is also negatively affected by the use of
chemicals. If G. scutellatus becomes re-established, it could cause severe and unhindered damage.
© ICFR 2009 Page 17 ICFR Central Regional Field Day
Visit to Visit to Visit to Visit to land preparation operationland preparation operationland preparation operationland preparation operation
G Stapelberg