herbage seed production - · pdf fileshort about bioforsk and seed production in norway...

22.11.2011

1

Herbage

seed

production - Based on Norwegian experiments

and practice

Trygve S. Aamlid and

Lars T. Havstad,

Bioforsk Landvik

Estonia, Dec 2, 2011

Contents

Sowing year:

Sowing

- Method (pure stand vs. cover crop)

- Sowing rate / row spacing

- Sowing depth

Weed management

Cover crop straw management

Autumn fertilization

Flower induction requirement

Seed harvest years:

Spring fertilization (type / rate / timing)

Weed management

Plant growth regulators

Plant protection (diseases and insects)

Irrigation

Pollination (clover)

Seed harvest methods

Straw management

Autumn / spring treatments

Introduction Short about Bioforsk and seed production in Norway

Climatic conditions

Species

Acreage and seed yields

Flower induction requirements

Seed crop management

22.11.2011

2

About Bioforsk

Bioforsk is a national R&D institute under the

Norwegian Ministry of Agriculture and Food.

450 employees. Our head office is located in Ås,

near Oslo.

Our research divisions are represented in all

major regions in Norway.

Bioforsk Landvik is located in the southern part

of Norway (58 oN). 16 employees.

Main research activities at Landvik are:

- Vegetables / early potatoes

- Seed production

- Turfgrass

Conventional Organic

Species Acreage (ha) Seed yield Acreage (ha) Seed yield

2009 2010 Average

2004-2010

2009 2010 Average

2004-2010

Timothy 1385 1829 690 56 75 490

Meadow fescue 501 746 590 13 31 420

Red clover, diploid 467 630 250 16 79 180

Red clover, diploid 20 49 180

Kentucky bluegrass 145 140 400

Creeping red fescue 66 203 400

Colonial bent grass 86 125 235

White clover 18 99 200

Smooth brome grass 54 71 490

Perennial ryegrass 33 64 1165

Cocksfoot 42 32 480

Reed canary grass 6 24 265

Sheep fescue 8 6 400 Total 2811 3971 85 185

Herbage seed production in Norway Timothy is the main species in Norwegian seed production (about 50% of total acrage),

followed by meadow fescue (18 %) and red clover (17%).

22.11.2011

3

T

Main (south-

eastern) seed-

growing area

(all species)

Central seed growing

area (only timothy)

Location of seed production in

Norway

Denmark

Sweden

Finland Norway

-10.0

-5.0

0.0

5.0

10.0

15.0

20.0

Jan

.

Feb

.

Mar

.

Ap

r.

May

Jun

.

Jul.

Au

g.

Sep

.

Oct

.

No

v.

De

c.

Me

an m

on

thly

te

mp

era

ture

,°C

Landvik (58.2°N)

Tallinn (59.3°N)

Apelsvoll (60.4°N)

Mean monthly temperatures in the southern

(Bioforsk Landvik) and northern (Bioforsk

Apelsvoll) part of the main Norwegain seed

growing area compared with Tallinn

22.11.2011

4

0

20

40

60

80

100

120

140

160

180M

ean

mo

nth

ly p

reci

pit

atio

n,

mm

Landvik

Tallinn

Apelsvoll

Mean monthly precipitation in the southern

(Bioforsk Landvik) and northern (Bioforsk

Apelsvoll) part of the main Norwegain seed

growing area compared with Tallinn

The number of fertile tillers at anthesis is a function of the number and size of

vegetative tillers present prior to flower induction.

Most temperate grasses have a dual flower induction requirement. They require short

days (SD) and/or low temperature in autumn followed by long days (LD) in

spring/summer. The means than only tillers that have reached a certain size in

autumn will become reproductive

Meadow fescue and red fescue have the longest requirements

for primary induction (16-20 weeks). Therefore, tillers of these

species must be formed in early autumn to become reproductive next year.

Timothy requires only Long Day for flowering. Spring-formed tiller can develop

ears (but they will usually be very short).

Short day

Low temp. 3-10 ˚C

Long day Secondary

induced Flowering

Primary

induced Vegetative

plant

Flower induction requirements Fundamental for understanding of seed crop management

Moderate temp. 12-18 ˚C

22.11.2011

5

Planting

date

Plant spacing

(cm)

Plants per

m2

Tiller

density/

m2

(1 Nov)

Seed

heads/

m2

Weight per

(unthreshed)

seed head

(mg)

Seed

yield/ha

June 15 30 x 30 11 1122 963 (86%) 92 813

July 15 15 x 15 44 1830 1396 (76%) 59 775

Aug. 15 7.5 x 7.5 178 2507 1481 (59%) 45 626

Tillers formed in late autumn will have a lower chance of becoming

reproductive and will also develop shorter/lighter seed heads than older tillers.

Effect of planting date (without cover crop) and plant density on seed yield

components of meadow fescue, Landvik 1999-2000)

Plants with few, but

strong early formed tillers

Plants with many, but late-

formed weak/small tillers

EXAMPLE

Seed crop management in

sowing year

Crop rotations and preparations:

Rotations with mostly spring-sown crops result in less problems with winter-annual

weeds.e.g. Poa trivialis and Matricaria inodora

Spring cereals are OK precrops, but row cultures, e.g. potatoes or vegetables,

are even better.

Have control of Elytrigia repens and other perennial weeds before sowing.

Conventional tillage (plowing) is recommended !

Early plowing in autumn in the year before sowing, followed by harrowing several times in

autumn if weather permits (autumn fallow), reduce seedbed weed content and enable

sowing with minimal loss of soil moisture in the following spring.

According to the Norwegian Seed Act, meadow fescue, perennial ryegrass, smooth

bromegrass and other large-seeded species can only grown for seed

on properties without wild oat (Avena fatua)

22.11.2011

6

Establishement in

cover crop vs. pure stand

Plant development (number and size of tillers) by

the end of the sowing year has a profound effect

on seed yield in the following year.

Cover crops normally have a negative influence

on seed yield due to competition, mainly for light

However, cover crops also may also have a

positive effect: Weed competition

Two-row barley and spring wheat are the most

common cover crops in Norwegian seed

production.

The negative effect of cover crop (2 row barley or spring

wheat) on seed yield in the first seed harvest year

compared with sowing in pure stand

(experiments in the1980’s)

Grass species % seed yield reduction

Landvik

(58oN)

Hellerud

(60oN)

Meadow fescue 24 59

Cocksfoot 38 70

Red fescue 84 86

Kentucky

bluegrass

83 95

Jonassen & Hillestad 1990

22.11.2011

7

With cover crop:

• Timothy

• Red clover

• White clover

• Perennial ryegrass

• Meadow fescue

• Colonial bentgrass (=browntop)

• Cocksfoot

• (Red fescue)

Establishment in

cover crop vs. pure stand

Without cover crop (pure stand):

• Red fescue

• Kentucky bluegrass

• Sheep fescue

• Smooth broomegrass

• Reed canary grass

Norwegian recommendations:

Sowing rate and nitrogen rate to

cover crop

Until a few years ago, we recommended to reduce cover crop sowing

rate and nitrogen rate by 30 % compared to standard practice in

barley or spring wheat production.

However, these recommendations were based experiments with old

cultivars of wheat and barley. Nowadays, cultivars have shorter and

stiffer stems and are less susceptible to lodging.

The following slides show results from recent experiments with cover

crop for establishment of meadow fescue, red fescue and white clover

22.11.2011

8

From the trials with establishment of

meadow fescue in spring wheat or barley

Experimental plan, meadow fescue :

Factor 1: Cover crop species 1. 2-row barley (cv. Annabell)

2. Spring wheat (cv. Bjarne)

Factor 2. Cover crop sowing rate A. Full sowing rate of barley and wheat (380 and 560 seeds /m2, respectively).

B. Sowing rate reduced by 30% compared to treatment A.

Factor 3. Nitrogen rate X. Full nitrogen rate (110 and 120 kg N/ha for barley and spring wheat, respectively)

Y. Nitrogen rate reduced with 30% compared to treatment X.

22.11.2011

9

Results

No lodging in any of the cover crops.

Cover crop sowing rates and N rate

had much less influence on total

profitability than in similar

experiments 20 years ago.

Tendency for nitrogen rate to be

more important that sowing rate in

barley.

Tendency for sowing rate to be more

important that nitogen rate in spring

wheat.

Net income over two years:

Results from red fescue

220 kg/ha 150 kg/ha 210 kg/ha 140 kg/ha

2-row barley ‘Annabell’ Spring wheat ‘Bjarne’

To

tal in

co

me

, s

ow

ing

ye

ar

+ 1

st

se

ed

ha

rve

st

ye

ar,

NO

K

Nitrogen rate: F = Full, R = - 30%

Yield of cover crop Seed yield

Sowing rates

22.11.2011

10

Seed crop establishment of

white clover, 2001-2003

FACTOR 1: Cover crop

1. Barley (cv. Kinnan), 130 kg/ha = 240 seeds /m2

2. Barley (cv. Kinnan), 200 kg/ha = 360 seeds/m2

3. Spring wheat (cv. Avle), 150 kg/ha = 350 seeds/m2

4. Spring wheat (cv. Avle), 225 kg/ha = 525 seeds/m2

FACTOR 2: Sowing rate / row spacing for white clover

1. Double row spacing (26-30 cm), sowing rate 1.5 kg/ha = 200 seeds/m2

2. Single row spacing (13-15 cm), sowing rate 3.0 kg/ha = 400 seeds/m2

(cover crop and white clover seeded in cross)

Results (mean of 7 trials)

Cover crop Sowing rate

(cover crop),

kg/ha

Grain yield in

sowing year

(kg/ha)

Seed yield,

first seed year

(kg/ha)

Barley (cv. Kinnan) 130 4910 211

Barley (cv. Kinnan) 200 5250 212

Spring wheat (cv. Avle) 150 3990 232

Spring wheat (cv. Avle) 230 4370 236

• Plots undersown in spring wheat gave the highest white clover seed

yield.

• No significant effect of cover crop sowing rate, nor white clover row

spacing or sowing rate, on white clover seed yield (not shown).

22.11.2011

11

Conclusion – cover crops

No reduction in cover sowing rate or N rate is

necessary when undersowing seed crops of

• Timothy

• Meadow fescue

• Red clover

• Perennial ryegrass

• White clover

30 % reduction in sowing rate and nitrogen rate

is still recommended when undersowing

• Cocksfoot,

• Colonial bentgrass (browntop)

• Red fescue

Spring 2-row barley and spring wheat equally good cover crops for grasses

Wheat allows for more light penetration during the first part

of the season, but barley is harvested 1-2 weeks earlier

Spring wheat slightly better than barley for white clover (and red clover ?)

Sowing in a pure stand

After an early harvested crop

(eg. early potatoes, vegetables etc).

Efficient weed control before sowing:

Barren (chemically fallowed) seedbed

Predominant method for species having

a long establishment period: Red fescue,

sheep fescue, Kentucky bluegrass,

smooth broomegrass, reed canary grass

For these species, the establishement

year without income is compensated by a subsidy

Typical procedure:

- Autumn plowing

- Prepare seed bed as normal in early spring

- Glyphosate 1-2 times before sowing,

no tillage that stimulate weed germination

- Sowing not later than 15 June – 15 July

depending on grass species and length of

growing season

22.11.2011

12

Barren (chemically fallowed seedbed:

Disturbance of outside rows will

stimulate germination of weeds

Sowing depth

010203040506070

1 2 3 4

% g

erm

inati

on

Sowing depth, cm

In pots with soil In field

The effect of sowing depth on germination of timothy seed

Timothy, Kentucky bluegrass and other small seeded species: Sowing depth less than 1 cm.

Large seeded species (meadow fescue, perennial ryegrass etc.): Sowing depth 1 - 2 cm

Seed-soil contact is very important !

Meadow fescue

Timothy

22.11.2011

13

0

100

200

300

400

500

600

0.5 1 2 4 8

Seeding rate (kg/ha)

Seed

yie

ld (

kg

/ha)

Effect of seeding rate on timothy seed yield in the first and second seed

harvesting year. Mean of two cultivars and fifteen trials.

(Nordestgaard, 1974)

0

100

200

300

400

500

600

0.5 1 2 4 8

Seeding rate (kg/ha)

Seed

yie

ld (

kg

/ha)

First seed year Second seed year

Sowing rates for grasses and clovers

Target seed crop densities :

- Grasses: 50 - 100 plants per m2

- Clovers: 10 - 50 plants per m2

Species Sowing rate,

kg/ha

Smooth bromegrass 5 - 10

Perennial ryegrass 5 -10

Meadow fescue 5 -10

Cocksfoot 4 -8

Red fescue 4 - 8

Kentucky bluegrass 4 - 8

Sheep fescue 6 -10

Reed canary grass 3 - 6

Timothy 3 – 5

Colonial bent grass 3 - 5

Red and white clover 2 - 4

The lowest sowing rate should be used under optimal germination condidtions

Recommended sowing rates

B.i. L.p.

D.g. F.p.

A.g. Ph.a.

Ph.p.

F.r. F.o.

P.p. A.c.

Primarily

forage

grasses

Primarily

turf-

grasses

22.11.2011

14

Row spacing

Many seed growers drill timothy,

cocksfoot, smooth bromegrass and

reed canary grass in every other row,

i.e. 24-30 cm row spacing

Most experiments show that seed

yield is more dependent on sowing

rate than on row spacing: With some

sowing machines, sowing in every

other row may be necessary to get

down to the optimal sowing rate, but

there is little effect of row spacing per

se.

Use of wide rows for mechanical

weed control is appropriate for

organic seed production, but so far, it

has not been common in Norway

Weed control in sowing year is critical to next year’s seed

YIELD (and quality)

Weed control in sowing year

The most problematic weeds in herbage seed are

winter-annual, biennial and perennial species that

germinate in the sowing year

Poa annua

Matricaria inodora

and Poa trivialis

22.11.2011

15

Effect of Poa annua density in the sowing

year on next year’s seed yield of

cocksfoot

y = -0.8x + 59

R2 = 0.78

0

100

200

300

400

500

600

700

0 10 20 30 40 50 60

% plant cover (Poa annua )

Seed

yie

ld (

kg

/ha

)

Rolston & Hare 1986

The competitive effect of weeds will be strongest :

• For species that establish slowly and are normally seeded without cover crop (e.g. red

fescue, Kentucky bluegrass, sheep fescue, smooth bromegrass, etc.)

Select Hussar

Unsprayed

Control of Poa annua and other grass weeds

in sowing year, sheep fescue

22.11.2011

16

Timing (spraying) Active ingredients Herbicide Rate per ha

To all grasses, with or without cereal cover crop:

When grass

seedlings have

1-2 leaves

Chlopyralid + fluroxypyr

+ MCPA Ariane S 2.0 – 3.0 L

Florasulam Primus 50 - 100 mL

Florasulam + fluroksypyr Starane XL 0.8 – 1.0 L

Against grass weeds in meadow fescue and perennial ryegrass

In autumn, after harvest of cover

crop Fenoxaprop-P-ethyl Puma Extra

0.5 – 1.0 L

(off-label)

To red / sheep fescue, Kentucky bluegrass and smooth bromegrass, without cover crop:

When grass seedlings have

2-3 leaves and are at least 1 cm

Iodosulfuron-methyl-

sodium

Hussar OD

(+ Renol)

50 mL

(off-label)

To red / sheep fescue, without cover crop:

When grass seedlings have 3-4

leaves and are at least 5 cm Chletodime

Select

(+ Renol)

0.4 – 0.5 L

(off-label)

Chemical weed control – herbicides approved for use in

grass seed crops in sowing year


White and red clover

When clover has developed

spade leaf to first triple leaf

MCPA MCPA

0.8 – 1.0 L

(lowest rate to

white clover)

Bentazon + MCPA Baragran M75

3.0 – 4.0 L

(lowest rate to

white clover)

Pyridate + MCPA Lentagran +

MCPA 1.5 kg + 0.7 L

Red clover only

When clover has developed

spade leaf to first triple leaf

Tribenuron-methyl +

MCPA*

Express +

MCPA

1 tablet + 0.5 L

(off-label)


clover seed crops in sowing year

• Express + MCPA is a rather tough treatment, but red clover seedlings will normally recover

• MCPA in tank mixture mitigates the harmful effect of Express

22.11.2011

17

1.0 tablet Express +

0.5 L MCPA 750

Evalutation of herbicides in red clover, sowing year

1.0 tablet Express

Unsprayed control Basagran M75, 3.5 L/ha

Management of cover crop straw

and stubble

22.11.2011

18

Stubble height / straw managements

In the period 2002-07, effects of different stubble heights and

cover crop straw managements was investigated in seed crops

of timothy, meadow fescue and red clover.

Vegetative develpoment in autumn after cover crop harvest was

affected by stubble height, but not by straw managements:

Increasing stubble height led to:

- Less light penetratration seed crops seedlings

- Reduced tillering

- Longer, but thinner (etiloated) leaves

Stubble height

Meadow fescue

(3 trials)

Timothy

( 3 trials)

tillers/

m2

Plant

height, cm

tillers/

m2

Plant

height, cm

Low (5-10 cm) 555 23 1288 20

High (20-30 cm) 432 37 1003 27

Registrations by the end of the growing seasong:

Seed yield (kg/ha)

Timothy Meadow

fescue

Red

clover

Number of trials 4 7 3

Factor 1. Stubble height at combining (mean of straw management)

1. Low (5-10 cm) 657 (100) 487 (100) 312 (100)

2. High (20-30 cm) 648 (99) 464 (95) 275 (88)

Sign. ns ns Almost sign.

Factor 2. Stubble and straw management (mean of two stubble heights)

A. Straw removed soon after harvest (control) 642 (100) 479 (100) 292 (100)

B. Straw chopped and spread during combining 664 (103) 472 (99) 295 (101)

Sign. ns ns ns

Management of cover crop stubble and straw

22.11.2011

19

• In timothy, red clover and meadow fescue, chopping of straw during cover

crop harvest seems to be an acceptable alternative to straw removal.

• It is very important that the chopped straw is spread evenly so that new tillers

are able to penetrate easily

• In wheat, even the chaff has to be spread evenly.

• Stubble height should not exceed 10 cm.

Management of cover crop stubble and straw

Conclusion

Autumn fertilization in sowing year Because of their dual flower

induction requirement, it has

always been recommendend to

apply fertilizer as soon as

possible after cover crop harvest

to all grass seed crops except

timothy

Typical rates are 30-40 kg N/ha

The exception for timothy has

been justified by the species’

single induction requirement

Some timothy sowings, are,

however, rather weak.

In 2007 we started experiments

to test if autumn fertilization might

improve first year seed yields

even of timothy

22.11.2011

20

RESULTS

0

5

10

15

20

25

30

35

40

45

0 200 400 600 800 1000

% incre

ase

in s

eed y

ield

Tiller density / m2 soon after cover crop harvest

Relationship between tiller density in autumn and timothy seed yield increase

in the following year due to N application immediately after cover crop harvest

Based on these results, we now recommend nitrogen after cover

crop harvest, even in (weak crops of) timothy !

Management in the

seed harvest years

22.11.2011

21

Species Recommended N

rates in the spring of

the seed harvest

years, kg/ha

Timothy 60 – 90

Meadow fescue 70 – 100

Red and white clover 0

Perennial ryegrass 100-120

Cocksfoot 90-110

Smooth bromegrass 50-80

Colonial bent grass 40-70

Kentucky bluegrass 50-70

Red fescue 50-70

Sheep fescue 50-70

Reed canary grass 80-100

Spring fertilization

Nitrogen has the strongest

impact on plant growth and

development, including the risk

for lodging

The highest N rates are always

used on sandy soils and on

soils low in organic matter.

Most seed production in

Norway is carried out on heavy

soils that have been cultivated

for many years, hence,

fertilization with K, P and other

nutrients have little influence on

seed yield. A typical fertilizer

type is NPK 25-2-6.

Clover seed crops normally do

not receive fertilizer

Timing of spring fertilization

Up to the late 1990’s, nitrogen was applied as early as possible in spring to all grass seed crops

except timothy. This was based on Danish trials showing early N input to be important for

species with a rapid generative development in spring.

For timothy, it was, however, recommended to postpone N fertilization until start of tiller

elongation in mid to late May, as this was believed to result in less lodging and longer seed

heads.

Since 1998, a total of 20 experiments on timing of N application has been carried out in timothy.

- 11 exp. with cv. Grindstad (main cultivar for south Norway, good regrowth ability, origin 59 oN)

- 9 exp with cv. Vega (winter hardy cultivar for the northern regions, origin 67 oN)

Experimental plan:

Factor 1: N-input in early spring (calcium-ammonium nitrate)

1. 25 kg N ha-1

2. 50 kg N ha -1

3. 75 kg N ha –1

Factor 2: N-input in late spring (mid-May, Z 31) (calcium nitrate)

A. 0 kg N ha -1

B. 25 kg N ha -1

C. 50 kg N ha -1

D. 75 kg N ha -1

Most trials treated with chemical growth regulators

cv. Grindstad

22.11.2011

22

The effect of different splitting of a total spring N-rate

of 75, 100 or 125 kg N on lodging at anthesis

Mean of twenty trials.

0

10

20

30

40

50%

lo

dg

ing

av

flo

wer

ing

Kg N ha-1 applied in early + late spring

Late

Early

100 kg N ha-1 125 kg N ha-75 kg N ha-1

Main N-

input in

spring

Lodging at flowering was more affected by the total N-rate than

by timing of N-application in spring.

0

20

40

60

80

100

25 50 75

Se

ed

yie

ld k

g 0

.1 h

a-1

kg N/ha in early spring

0

25

50

75

Kg N ha-1 in

late spring

0

20

40

60

80

100

25 50 75

Seed y

ield

, kg h

a-1

kg N/ha in early spring

0

25

50

75

Kg N ha-1 in

late spring

Grindstad (11 trials) Vega (9 trials)

The effect of early and late N-rates on seed yield

in timothy ‘Grindstad’ and ‘Vega’

Both cultivars produced the highest seed yield when the main N-application was

given in early spring.

Optimal distribution was 75+0 kg N/ha in ‘Grindsstad’ and 50+25 kg N/ha in ‘Vega’

No difference in optimal N-strategy depending on age of crop

(first or second seed harvest year)

22.11.2011

23

Timothy: Adjusting the second N input at early tiller

elongation (15-20 May) depending on

chlorophyll readings

Optimal N fertilization depend on soil fertility, climate, tiller density etc.

and may differ between locations.

Aim: Adjust the supplemental N-rate in late

spring (Z 31) depending on plant requirement

using a chlorophyll-meter (quick response, easy

to use).

(Herbage N-analysis is normally a too

expensive and time-consuming method)

We used a handheld chlorophyll-meter :

Yara N-Tester® (YNT)

The chlorophyll -readings at Z 31 were taken at the midpoint of the

last fully developed leaf.

R2 = 0,460

0

20

40

60

80

100

120

140

0 50 100 150 200 250 300 350 400 450 500

Chlorophyll readings (HNT-values)

Op

tim

al N

-in

pu

t a

t Z

31

,kg

N h

a-1

Timothy ‘Grindstad’: Relationship between

optimal N-input

at early tiller elongation and chlorophyll readings

YNT-value 350:

Opt.=26 kg N ha-1

’Grindstad’

In cv. Grindstad we found that the need for supplemental N at early tiller elongation could be predicted by the model:

Optimal N-input at Z 31 (kg N ha-1) =

-0.37 x measured YNT-value + 156

22.11.2011

24

Spring N recommendations for timothy

Conclusion

The recommended N-strategy to seed crops of timothy is to split a total N rate of 70-90 kg ha-1 into a main application in early spring (50-75 kg N ha-1) and a supplemental application at the start of tiller elongation in mid May (Z 31)

In cv. Grindstad, the supplemental N application at early tiller elongation should be adjusted based on chorophyll readings.

Ugrasforsøk i frøeng

Kirsten Semb Tørresen, Bioforsk Plantehelse

Forsøksringer i Vestfold, Buskerud, Telemark, SørØst, Trygve S. Aamlid, Bioforsk Øst Landvik

Weed control in the

seed harvest year

Photo: John Ingar Øverland

22.11.2011

25

• Weed compete with seed crops

and reduce seed yield (discussed under sowing year)

• Weed seeds and seeds of other

cultural plants contaminate seed

lots.

• Some species are very difficult to

separate during cleaning. This

will increase clean-outs, lower

seed yields, and may, in the

worst case, lead to rejection of

the seed lot.

Weed control

• Rumex – example of noxious weed

Requirements to certified seed

Class C1 (certified seed)

% pure

seed

Maximum weed content, % Rumex

seeds

Minimum

Germination Total One

species

Elytrigia

repens

Timothy 96 1.5 1.0 0.3 5 in 10g 80

Meadow fescue 95 1.5 1.0 0.3 5 in 50g 80

Red clover 97 1.5 1.0 - 10 in 50g 801)

1) Including up to 40 hard seeds

22.11.2011

26

Generally speaking, dicots cause most problems in clover

seed crops, while other grasses cause most problems in

grass seed crops

Plantago major in white clover Elytrigia repens in meadow fescue

Separation of seeds with nearly same size and / or

weight causes problems during seed cleaning

Timothy Matricaria

inodora Poa annua Poa triviális

Seed cleaning plants usually manage to clean out the difficult species (e.g. Matricaria

inodora) from timothy and red clover, but the penalty in seed yield is often high

22.11.2011

27

Poa trivialis – an increasing problem

in Norwegian grass seed crops


Against broad-leaved weeds in all grass seed crops

When grass seed crop is

10 cm high in early spring

Chlopyralid + fluroxypyr

+ MCPA Ariane S 3.0 – 3.5 L

Florasulam Primus 100 - 150 mL

Florasulam + fluroksypyr Starane XL 1.2 – 1.5 L

Against broad-leaved weeds in timothy, smooth bromegrass and

colonial (browntop) bentgrass


10 cm high in early spring Tribenuron-metyl Express 1.5 – 2.0 tabl.

Against grass weeds and broad-leaved weeds in timothy, red fescue, sheep fescue,

Kentucky bluegrass and smooth bromegrass


10 cm high in early spring

Iodosulfuron-methyl-

sodium

Hussar OD

(+ Renol)

50-100 mL

(off-label)

Against grass weeds, esp. Elytrigia repens in red and sheep fescue

When grass seedlings have 3-4

leaves and are at least 5 cm high Chletodime

Select

(+ Renol)

0.4 – 0.5 L

(off-label)


grass seed crops in the seed harvest years

22.11.2011

28


Against broad-leaved weeds, esp. Matricaria

Temperature >10˚C,

often spilt application Bentazone Baragran SG 1.6 kg

Against grass weeds

Elytrigia repens 4-5 leaves Cycloxydim Focus Ultra 4-5 L/ha

Propakvizafop Agil 100 EC 1.2 – 1.5 L/ha

Poa annua in bloom Chletodime Select + Renol 0.4-0.5 L/ha


clover seed crops in harvest year

Chemical growth regulators

Spraying with chlormequat chloride (Cycocel) or trinexapac-ethyl (Moddus) reduce stem elongation and increase seed yield substantially in many species. Cycocel has been approved in Norwegian seed production for more than 20 years, and Moddus since 2001.

The seed yield increase is usually due to less lodging, causing more transfer of assimilates to seed heads instead of to stems and new tillers. Seed heads are often 20-30 % heavier than in untreated crops.

Growth regulators usually delay seed maturity by 3-4 days. In experiments where all plots were harvested on the same date, germination was often 2-4 units lower on regulated than on unsprayed plots

Growth regulators, especially Moddus, should be used only under favourable growing conditions, and not in crops that are stressed due to drought, night frost, tough herbicide applications etc. Timing of Moddus applications is quite flexible, so it is advisable to wait for good growing conditions.

22.11.2011

29

Plant height at

flowering, cm

Lodging at seed

harvest,%

SE

Norway

(7 trials)

Central

Norway

(4 trials)

SE

Norway

(7 trials)

Central

Norway

(5 trials)

Unsprayed control 102 108 37 68

CCC 750, 2.67 L/ha*, start of tiller elongation

(Z 31)

100 104 14 58

Moddus, 0.6 L/ha, start of tiller elongation (Z 31) 99 109 21 38

Moddus, 0.6 L/ha flag leaf stage (Z 42-48) 97 103 17 25

CCC 750, 2.67 L/ha at Z 31 +

Moddus 0.3 l/ha3) at heading (Z 52-55)

102 105 9 32

P% <5 13 <1 <1

LSD5% 4,7 - 13 22

Growth regulation, timothy: Plant height and lodging

*Always use adjuvant with CCC.

Growth regulation, timothy: Seed yield

Unsprayed

control

Moddus

22.11.2011

30

Treatments

Timothy seed yield (kg/ha)

SE Norway

(7 trials)

Central Norway

(5 trials)

Mean

(12 trials)

kg/ha Rel kg/ha Rel kg/ha

Rel

Unsprayed control 610 100 477 100 554 100

CCC 750, 2.67 l/ha1), start of tiller elongation (Z31) 760 125 583 122 686 124

Moddus, 0.6 l/ha2), start of tiller elongation (Z31) 720 118 684 143 705 127

Moddus, 0.6 l/ha2), flag leaf stage (Z 42-48) 704 115 726 152 713 129

CCC 750 2.67 l/ha1) at Z31 + Moddus 0.3 l/ha3) at

heading (Z52-55)

766 126 727 152 750 135

P% <5 <1 <0,1

LSD5% 106 125 82

SE Norway (58-61°N): Combination of CCC (2.67 l /ha) at Z 31 and Moddus (0.3 l/ha) at heading gave the highest seed yields (26 % higher than unsprayed control)

Growth regulation – timothy: Seed yield

*Always use adjuvant with CCC.

Moddus Unsprayed

control

Growth regulation – meadow fescue

22.11.2011

31

First Moddus application

(start of tiller elongation,

Z 31)

Second Moddus application

(flag leaf stage, Z 42-48)

Seed yield

(Mean of 5 trials in 2001-02)

Kg/ha Rel.

1 Unsprayed control 577 100

2 0.3 L/ha (75 g a. i./ha) 626 109

3 0.6 L/ha (150 g a. i./ha) 696 121

4 0.9 L/ha (225 g a. i./ha) 719 125

5 0.3 L/ha ((75 g a. i./ha) 604 105

6 0.6 L/ha (150 g a. i./ha) 665 115

7 0.9 L/ha (225 g a. i./ha) 675 117

Growth regulation – meadow fescue: Seed yield

Recommendation: Moddus (0.6-0.9 L/ha) at Z 31-Z44 (when growing conditions are favourable)

CCC has no effect on seed yield in meadow fescue.

In another experimental series we looked at:

Split N application and growth regulation strategies in

meadow fescue (mean of 4 trials)

At the start of tiller elongation (Z31) two out of four replications were sprayed with 0.6 L trinexapac-ethyl (Moddus) pr ha, while the two remaining replications were unsprayed.

Treat

-

ment

Applied N rate (kg / ha)

In early spring

(calcium-

ammonium nitrate)

At the start of tiller

elongation (Z 31)

(calcium-nitrate)

Early heading (Z 52)

(calcium-nitrate)

1 90 0 0

2 30 60 0

3 60 30 0

4 60 0 30

5 30 30 30

Experimental plan:

22.11.2011

32

0

10

20

30

40

50

60

70

90+0+0 30+60+0 60+30+0 60+0+30 30+30+30

% l

odgin

g a

t fl

ow

eri

ng

Applied N rate (kg/ha) in early spring + at Z 31 + at Z 52

No Moddus

With Moddus

Important to avoid lodging at flowering for optimal pollination.

Lodging was to a certain extent controlled by N strategy

Only 3-8 % lodging on plots sprayed with Moddus, regardless of N strategy

Results: Lodging at flowering

0

100

200

300

400

500

600

700

800

900

90+0+0 30+60+0 60+30+0 60+0+30 30+30+30

Seed y

ield

(kg/h

a)

Applied N rate (kg/ha) in early spring + at Z 31 + at Z 52

No Moddus

With Moddus

Seed yield was always highest on plots sprayed with Moddus, regardless of N strategy.

On non-sprayed plots, split application was favorable with regard to seed yield.

On plots sprayed with Moddus, split N application had no positive effect on seed yield compared to one application in early spring.

Results: Seed yield

22.11.2011

33

Growth regulation – red clover

100108

121

110 113

80

100

120

140

0

200

400

600

Pla

nt

he

igh

t, c

m

Se

ed

yie

ld k

g /

ha

Seed yield Plant heigt at flowering

Growth regulation – diploid red clover

Application of Moddus to cv. Nordi and Lea. Mean of five trials

Note: We have NOT had similar seed yield increases in tetraploids !

22.11.2011

34

Application at

Z 31-32

Application at

Z 45-51

Cocks

-

foot

Smooth

brome-

grass

Per-

ennial

rye-

grass

Reed

canary-

grass

Creeping

red

fescue

Colonial

bent

(brown-

top)

Ken-

tucky

blue-

grass Product L/ ha Product L/ha

Unsprayed control, kg/ha 566 725 1233 586 556 283 541

CCC 750* 1.33 131 156 - - 99 126 119

CCC 750 2.67 142 157 - - 110 137 119

Moddus 0.3 126 101 109 104 100 127 121

Moddus 0.6 143 108 107 104 118 137 120

Moddus 0.9 - - 111 - - - -

Moddus 0.3 122 107 109 108 115 117 -

Moddus 0.6 135 133 110 108 117 113 -

Moddus 0.9 - - 116 - - - -

CCC 750 1.33 Moddus 0.3 146 138 - - 123 134 -

CCC 750 2.67 Moddus 0.9 149 138 - - 142 129 -

LSD 5% 71 168 103 ns 120 57 68

No of trials 3 1 2 2 5 5

Growth regulation – effect on seed yields in other

species (relative figures, unsprayed control = 100)

Plant protection - diseases

Timothy

Meadow fescue

The most common diseases in Norwegian

grass seed crops are Drechslera spp.

Starts with small, brown spots, that increase in size

during the growing season. Eventually the infected

leaf becomes totally brown (wilted).

Infection comes from from seed and plant material

left in the field (e.g. straw, wilted leaves etc.)

22.11.2011

35

Treatments

Fungicide

dose per ha

Fungicide

(g a.i. pr ha)

Timing

Seed yield, kg/ha

(3 trials)

Kg/ha Rel

1. Unsprayed - - 497 100

2. Acanto P 1000 g 300/80 Z 31 539 109

3. Stereo 1200 ml 75/300 Z 31 530 107

4. Proline 600 ml 150 Z 31 524 106

5. Acanto P 1000 g 300/80 Z 49 546 110

6. Stereo 1200 ml 75/300 Z 49 552 111

7. Proline 600 ml 150 Z 49 559 113

8. Stereo + Stereo 750 + 750 ml 47/188 + 47/188 Z 31 + Z 49 573 115

9. Proline + Proline 400 + 400 ml 100 + 100 Z 31 + Z 49 540 109

10. Acanto P + Proline 750 g + 400 ml 225/60 + 100 Z 31 + Z 49 544 110

P % >20

Spraying against diseases (meadow fescue): Fungicides tested: Acanto prima (cyprodinil+pikoksystrobin), Stereo (propikonazol + cyprodinil)

and Proline (protiokonazol)

If timothy or meadow fescue leaves show signs of disease infection before or at anthesis,

fungicide application is usually profitable.

Optimal timing for fungicide application depends on weather conditions in the growing season

(largest diseases pressure under humid conditions).

In wet springs: Tank mix fungicides when applying growth regulators !

The timothy flies lay their eggs near the base of laminae.

Plant protection - Insects

Timothy flies (Nanna sp.)

Weevils of the timothy flies (Nanna flavis and Nanna armillata) feed on the ear before heading.

In South Norway, eggs will normally be found around mid May (i.e. optimal time for spraying).

Spraying only if eggs are found on more than around 5 % of tillers.

Use a pyrethroid (e.g. Fastac (alfacypermetrin) or Sumi-alpha (esfenvalerat))

22.11.2011

36

Grass and cereal mite (Siteroptes graminum)

Plant protection - Insects

Small mites that live within leaf sheaths and may

cause damage by sucking cell contents from the

straw, resulting in visual wilted (white) seed heads in

many species (e.g. fescues).

The wilted panicle can be pulled out of the sheath

without resistance.

The mites don’t move much, and the problem will

therefore increase with the age of the seed crops.

In second year and older seed crops of red fescue,

Kentucky bluegrass and colonial bentgrass,

insecticides will usually have an positive effect on

seed yield.

We also recommend routine application in insecticide

in third year crops of meadow fescue.

Use a pyrethroid (e.g. Fastac (alfacypermetrin)

Tank mix with growth regulators

Clover seed

weevils (Apion sp.)

Plant protection – harlmful

insects in clover Lesser Clover Leaf

Weevil (Hypera

nigrirostis)

22.11.2011

37

Red clover seed weevils

Apion apricans

Apion trifolii

Apion assimile

The lesser clover seed weevil

Hypera nigrirostris

Photos:

John Ingar Øverland

and Jon Anders Otterstad

22.11.2011

38

Treatment Seed yield (kg/ha)

2008 (3 trials) 2009 (4 trials) Both years Rel

1. Non sprayed control 416 240 315 100

2. Fastac 50, bud stage 354 208 271 86

3. Biscaya, bud stage 432 241 323 103

4. Fastac, early flowering 368 221 284 90

5. Biscaya, early flowering 417 221 305 97

6. Fastac + Biscaya 383 217 289 92

7. Biscaya + Fastac - 212 92

LSD, 5% 53 - 26

In most Norwegian experiments, spraying had had no positive effect on seed yield.

Since the weevils have low mobility, spraying is only recommended in seed crops that are

close to previous years’ seed crops where insect damage was documented

Even when used after sun set, insecticides probably have a negative effect on pollinating

insects.

Insect control in red clover Norwegian trials 2008 and 2009

Pollination - clover

Flowers of red clover and white clover are self

sterile and must be cross-pollinated to produce

seed.

Both honey bees and bumble bees are able to

pollinate red clover, but bumble bees are more

efficient: A rule of thumb is:

1 bumble bee = 2.5 honey bees

Both groups are equally efficient in white clover.

Bumble bees flies/pollinates at lower temperatures

than honey bees.

Only bumble bees with a long tongue (probiscis) are

able to reach the nectar in red clover.

Unfortunately, the occurrence of long-tongued bees

has decreased during the past 50 years

22.11.2011

39

Pollination - red clover

Red clover seed growers can increase the

natural population of bumble bees on their

farm by sowing attractive plants

Early feeding on Salix-species in spring is

important for bumble bees to survive.

An attractive herb species is Lacy

phacelia (Phacelia tanacetifolia). Can be

sown in “stripes” surrounding the seed

crop to attract bees. Flowers around 6

weeks after sowing. Must be cut down

when red clover starts to flower.

Pollination - red clover

Swedish seed yield investigations on farms with or without bee hives in red

clover seed crops.

Norwegian surveys have not been equally convincing. Nevertheless, placing bee hives in

seed crops of red clover is recommended in all Nordic countries, normally at a density

of 1 bee hive per 0.2-0.3 ha.

Cooperation with bee keepers is necessary.

22.11.2011

40


The traditional harvest recommendation for grass seed crops in Norway has been direct

combining, in many species followed by a second combining 4-8 days later.

The timing of the first combining, and thus the need for a second combing, depends on the

species’ evenness of ripening and susceptibility to seed shattering. Timothy and meadow

fescue are both susceptible to shattering and should be combined directly at 30-35% seed

moisture content (SMC) By contrast, direct combining of Kentucky bluegrass and smooth

bromegrass can wait until SMC is about 20%.

When direct combining seed at 30-35% SMC, threshing has to be very gentle in order not to

damage seed germination capacity

Over the past couple of decades, combines have become bigger, and the percentage of seed

growers having their own combine has decreased. This has led to many seed crops being

combined only once, at a suboptimal seed moisture content.

The alternative to direct combining is swathing. Potential benefits include:

- Faster combining

- Reduced loss of seed due to shattering.

- Harvested seed needs less drying

- Better germination

In 2009, new experiments started on direct combining vs. swathing of timothy seed crops.


22.11.2011

41

Experimental plan

Treat-

ment

Timing Treatment

1 T1+ T3 Early swathing at 40-45 % SMC. Combining of windrows

about one week later (T3).

2 T2+T3 Late swathing at 30-35 % SMC, about 4 days after T1.

Combining of windrows at T3.

3 T2 + T3 Direct combining at 30-35 % SMC (T2). Second combining

about three days later (T3).

4 T3 Direct combining at 20-25 % SMC. Only one combining.

Swathers used in trials

2010: Hesston swather.

Width 3.68 m.

Stubble height: 15-20 cm.

2009: BCS Duplex.

Width 1,8 m.

Stubble height: 5 cm.

22.11.2011

42

Year

Treatment

Swathing Combining Precipitation

(mm) between

swathing and

seed harvest

Date SMC

%

Date SMC

%

2009 1 Early swathing 29 Jul. 43.9 6 Aug. 28.8 67

2 Late swathing 5 Aug. 37.3 12 Aug. 17.1 12

3 Combining 2x 6 Aug. (1)

12 Aug.(2)

36.0

19.4

4 Combining 1x 12 Aug. 20.8

% Seed Moisture Content (SMC) at

swathing and combining

2010 1 Early swathing 31 Jul. 46.8 8 Aug. 19.6 17

2 Late swathing 8 Aug. 32.6 16 Aug. 20.4 51

3 Combining 2x 8 Aug. (1)

16 Aug.(2)

32.6

20.7

4 Combining 1x 16 Aug. 19.7

Harvest method

Seed yield (kg/ha)

2009 2010 Mean Rel.

Number of trials 1 1 2 2

1. Early swathing (40-45% SMC) 1222 1110 1166 100

2. Late swathing (30-35% SMC) 1048 829 938 80

3. Combining (2x), First. 915 802 858

Second 348 329 338

Total 1263 1130 1197 103

4. Combining (1x) 1018 685 852 73

P% 5 3 3

LSD 5% 180 293 226

Results - Seed yield (kg/ha)

Highest seed yield was obtained on plots being swathed early (treatment 1) and

on plots being combined twice (treatment 3).

22.11.2011

43

Harvest method

TSW (mg)

Germination (%)

2009 2010 Mean

Number of trials 2 1 1 2

1. Early swathing (40-45% SMC) 554 96 93 95

2. Late swathing (30-35% SMC) 573 96 98 97

3. Combining (2x), First. 606 89 94 92

Second 548 94 94 96

4. Combining (1x) 594 95 97 95

P% <0.1 1 >20 >20

LSD 5% 17 3 - -

Results – Seed quality

Germination of swathed seed (treatment 1 and 2) was high in 2009, but slightly lower for early

swathed seed (treatment 1) in 2010 .

In 2009, the lowest germination was found in seed that was combined directly at 36 % SMC.

Based on this, the optimal timing of swathing seems to be when SMC is between 40 and

45 %. Earlier swathing (47% SMC ) reduced germination, while later swathing (SMC <

35%) increased seed shattering and lowered seed yield.

Swathing vs. direct combining vs. desiccation of red clover seed crops is now being

compared in a new experimental series started 2010 (so far only one trial)

Experimental plan:

1. Swathing when 50 % of seed heads are mature, drying in windrows before seed

harvest.

2. Swathing when 65 % of seed heads are mature, drying in windrows before seed

harvest.

3. Direct combining when about 80 % of seed heads are mature.

4. Desiccation with Reglone (diquate), 2.5 L/ha, when 65 % of seed heads are

mature. Combining about one week later (Control).

Seed harvest methods - Red clover

22.11.2011

44

Harvest method

TSW

(g)

Germination Seed yield

% Kg/ha Rel

1 Early swathing, 50% mature seed heads 1.82

81 274 100

2 Late swathing, 65% mature seed heads 1.91

86 263 96

3 Direct combining, 80 % mature seed heads 1.88

87 285 104

4 Desiccation with Reglone one week before harvest 1.93

90 255 93

P% 11

>20 >20

Seed harvest methods - Red clover

This trial confirms earlier findings that

swathing gives no special advantage in red

clover compared to direct combining with or

without desiccation.

Our present recommendation:

Desiccation with Reglone (diquat), 2.5 L /ha)

when 65 % of seed heads are mature.

Combining about one week later

It is very important to get the seed ventilated or into the drying bin within 2-3 hours after direct combining. This is especially important in clover !

To keep the seed cool, the ventilator must be run continuously and/or the seed circulated during the first two days after harvest, irrespective of weather conditions (also in rain).

When the seed moisture content is below 18%, the ventilator can be switched off during night. Check relative humidity of air.

In Norway, seed are to be dried down to 12 % SMC. This correspond to an ambient moisture content of about 50 %. Additional heat may be needed to lower the relative humidity during the last drying phase.

Some words about seed drying

22.11.2011

45

Straw management methods

Straw management in timothy

and meadow fescue

In both species, straw removal soon

after harvest was recommended

practise until about five years ago.

However, much of the seed production

takes place on farms without livestock:

The market for straw has decreased.

Straw removal takes away valuable

nutrients from soil

Main objective for experimental series:

Find alternatives to straw removal.

22.11.2011

46

Straw chopped at the back of the combiner Straw chopped by a tractor mounted flail-

chopper soon after harvest.

Two different experimental series in

timothy and meadow fescue, 2000-2005

• In both series, different straw chopping methods were tested.

• The combine harvesters used in the trials were ordinary farm machinery.

Combine width varied from 8 to 13 feet (2.4 - 4.0 m).

Stubble height 30 cm

Experimental series 1: Results

• Long stubble had a negative influence on seed yield

• Field burning produced the best seed yields

• Straw chopping at harvest did not reduce seed yield compared to straw removal

22.11.2011

47

However, we do not recommend

open field burning immediately

after harvest near roads and in

densely populated areas

Open field burning of evenly

spread straw soon after harvest

produced the highest seed yield

Open field burning soon after seed harvest

Seed yield

Straw and stubble management treatments

Timothy Meadow

fescue kg

ha-1 Rel. kg

ha-1 Rel.

1. Straw removed after harvest (control) 617 100 734 100

2. Straw chopped and spread during combining 655 106 733 100

3. Straw and stubble chopped with a tractor driven chopper 674 109 751 102

4. Straw chopped twice (first with the combine straw chopper

and then after harvest with a tractor driven chopper) 673 109 758 103

P% > 20 > 20

Effect of various straw chopping methods on seed yield.

Mean 3 trials in timothy and 5 trials in meadow fescue

• No negative effect of straw chopping on seed yield.

Experimental series 2: Results

22.11.2011

48

• In both timothy and meadow fescue, straw chopping is an acceptable

alternative to straw removal

• For most seed growers, the most efficient and less laborious method will be

to chop the straw directly during seed harvest.

• The chopped straw has to be spread evenly som that light penetration to the

new tillers is not inhibited.

• Stubble height should be kept at a low level (less than 10 cm) during

combining. Alternatively, the stubble ought to be chopped afterwards.

Straw management: Conclusions

Species Normal time for

seed harvest

N rate,

kg/ha

When to

fertilize

Timothy 1-15 Aug 0 -

Meadow fescue 20-30 July 20 - 601 1 Aug.

Perennial ryegrass 25 July-10 Aug 0 -20 1 Sep. ?

Cocksfoot 15-25 July 30 - 40 1 Sep. ?

Smooth bromegrass 15-25 Aug. 40-50 1 Sep. ?

Colonial bentgrass 15-25 Aug. 20-60 (depending

on variety)

1 Sep. ?

Kentucky bluegrass 10-20 July 40-50 1 Oct.

Red fescue 15-25 July 30-40 1 Sep.

Sheep fescue 5 – 15 July 50-70 1 Oct.

Reed canary grass 15 – 25 July 80-100 1 Sep. ?

Autumn fertilization in the seed

harvest years

1 : Highest rate when utilizing regrowth for forage

? : Optimal timing not known from Norwegian trials

22.11.2011

49

Timing of autumn fertilization

Meadow fescue vs. Kentucky bluegrass

Optimal time for autumn fertilization depends on the length of the primary induction

requirement and the tendency for various species to become too dense

Meadow fescue has a very long primary induction requirement and should

therefore receive nitrogen as early as possible after seed harvest

In Kentucky bluegrass, the objective of autumn fertilization is not to promote new

tillers but to increase tiller size

Next year’s

Seed yield, kg/ha

Application of

40 kg N/ha

Meadow

fescue

Kentucky

bluegrass

1 Aug. 907 263

1 Sep. 824 334

1 Oct. 774 363

Management of regrowth in meadow fescue

250

350

450

550

650

750

850

No cutting/burning

Cutting onSept 5

Cutting onOct 10

Burning inearly spring

Se

ed

yie

ld (k

g/h

a)

Timing of cutting or burning in autunm/early spring

Mean of seven trials in 1999-2001

When seed crops of meadow are fertilized as early as 1 Aug, they will

produce significant amounts of dry matter in autumn

How to handle this regrowth ?

1. Utilize regrowth for a forage cut in autumn ?

2. Burn or chop the wilted regrowth in the following spring ?

Early spring

burning gave

the highest

seed yield)

Unlike timothy, the apex of meadow fescue is vulnerable to freezing damage in areas

with unstable snow cover / fluctuating winter temperatures.

If regrowth of meadow fescue is to be utilized for forage, the cut should not be taken

later than 15 September

Leaving the regrowth as a protective cover until next spring produced the highest yield.

22.11.2011

50

Negative aspects:

No removal of protecting layer of stubble/regrowth during autumn/winter → less

winter damages.

Burning remove wilted leaves / stubble and improve light conditions in spring (less

light competition between tillers) → More primary induced tillers survive and become

reproductive

Positive aspects of spring burning:

Some farmers don’t like field burning

since fire may get out of control due

to wind etc.).

Smoke emission (although the smoke

problem is usually far less in spring

than when buring straw in autumn

Risk for damage to tiller apices in

areas with early start of growth in

spring

Experimental series, 2002-04:

Timing of burning or chopping in spring in

seed crops of meadow fescue (mean of 4 trials)

Treatment Seed yield

(kg/ha) Rel

1. No burning or cutting in spring (control) 410 100

2. Chopping with pasture cutter before start of growth 466 114

3. Similar to treatment 3, but 7-10 days later 466 114


5. Burning before start of growth in spring. 492 120



Spring burning poduced the highest yields, but must be done before start of spring

growth.

If weather conditions prevents burning before green-up:

Chopping of the wilted regrowth / stubble later in spring is a safer alternative.

22.11.2011

51

Seed grower’s calendar: Example: Timothy – Sowing year

When What to do

Establisment with cover crop

Spring

Undersowing in an early and stiff cultivar of spring wheat or spring 2-row barley. As

long as lodging is avoided, cover crop sowing rate and nitrogen rate can be the same

as for ordinary barley or wheat crops without seed crop establishment. Sowing rate /

row spacing of timothy: 3-5 kg/ha / 12-30 cm. Optimal sowing depth for timothy: 0.5-1.5

cm.

Timothy 1-2 leaves, weeds

2-4 leaves

Herbicides against broad-leaved weeds: Either (1) Ariane S (2.0-2.5 L/ha), (2) Starane

XL (0.8-1.0 L/ha) or (3) Primus (0.05-0.1 L/ha).

Cover crop stem

elongation/heading

Supplemental nitrogen input; application of fungicide, insecticide and plant growth

regulator to cover crop.

August - September

Cover crop harvest as early as possible. Cover crop straw can be cut and returned.

Leave as short stubble as possible, chop the straw and spread it evenly, spread the

chaff, avoid loss of light kernels.

Shortly after cover

crop harvest

If less than 500 timothy tillers per m2: Autumn fertilization, 30 kg N/ha

Establishment in pure stand

Spring /early summer Prepare for seed crop with a row crop / fallow with thorough weed control

Not later than 10 Aug.

Sowing: Sowing rate / row spacing of timothy: 3-5 kg/ha / 12 – 30 cm. Incorporation of

30-40 kg N/ha into seedbed before sowing or surface application shortly after seedling

emergence.

Timothy 1-2 leaves, weeds

2-4 leaves

Herbicides against broad-leaved weeds: Either (1) Ariane S (2.0-2.5 L/ha), (2) Starane

XL (0.8-1.0 L/ha) or (3) Primus (0.05-0.1 L/ha).

SUMMARY

When What to do

Shortly before green-up, soil

temp. 4-5°C

Spring fertilization, 50-75 kg N/ha, lowest rate in dense crops and on soils rich in

organic matter. P and K inputs, and thus fertilizer type, should be determined from soil

analyses.

Timothy 10 cm high.

Broad-leaved weed control if necessary: Either (1) Ariane S (3.0-4.0 L/ha), (2) Starane

XL (1.2-1.5 L/ha), (3) Primus (0.10-0.15 L/ha) og (4) Express (1.5-2.0 tabl./ha). Ariane S

should only be used only if temperature is higher than 10°C. If seed crop is well

established and Poa trivialis is a problem: Use Hussar OD, 50-100 mL/ha + Renol (0.4-

0.5 L/ha). Express and especially Hussar retards timothy, but the seed crop will usually

recover.

Early stem elongation,

usually mid-May, Z 31

Supplemental fertilizer, 0-40 kg N/ha, highest rate in crops that are open and have

chlorophyll-readings (Yara-N-test values) less than 350.

Early stem elongation,

usually mid-May, Z 31, only

if growing condtions are

conducive

Chemical plant growth regulation: Cycocel 750 (2-2.75 L/ha + adjuvant) or Moddus,

0.5-0.6 L/ha. Tank mix with pyretroid (e.g. Fastac 50 (0.4 L/ha) if eggs of timothy flies

are found on more than 5% of tillers.

Between tiller elongatioin

and flowering

Spray one of the fungicides Acanto Prima (0.8-1.5 kg/ha) or Stereo 312.5 EC (0.7-1.5

L/ha) if visible attack of Drechslera leaf spot or other diseases.

At heading Second application of Moddus (0.3 L/ha) in years with high lodging pressure

No later than flowering Hand weeding of Rumex sp., Matricaria inodora and other noxious weeds or weeds

that are difficult to separate from timothy seed.

Last days of July /

first days of August

or

First week of August

Swathing when seed moisture content (SMC) is 40-45%. Leave the windrow on a high

stubble. Windrows are usually combined when SMC is down to 20% after one week’s

curing. Drum periphery speed: 20-23 m/s, concave clearance 8-12 mm front / 4-6 mm

rear.

Gentle direct combining when SMC is 30-35 %. Drum periphery speed 15 m/s, concave

clearance 20-30 mm front / 10-15 mm rear. Second combining of straw after minimum 3

days windrow curing.

Straw can either be baled off or cut and spread evenly. Stubble height should not

exceed 10 cm.

Autumn Autumn fertilization not necessary after seed harvest.

Seed grower’s calendar: Timothy - Seed harvest years

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