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TRANSCRIPT
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
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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%).
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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
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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)
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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
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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
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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.
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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
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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
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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
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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
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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
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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
Timing (spraying) Active ingredients Herbicide Rate per ha
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)
Chemical weed control – herbicides approved for use in
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
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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
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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
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• 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
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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
Timing (spraying) Active ingredients Herbicide Rate per ha
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
When grass seed crop is
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
When grass seed crop is
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)
Chemical weed control – herbicides approved for use in
grass seed crops in the seed harvest years
22.11.2011
28
Timing (spraying) Active ingredients Herbicide Rate per ha
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
Chemical weed control – herbicides approved for use in
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
Seed harvest methods
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.
Seed harvest methods
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
4. Similar to treatment 3, but 15-20 days later 438 107
5. Burning before start of growth in spring. 492 120
6. Similar to treatment 6, but 7-10 days later 406 99
7. Similar to treatment 6, but 15-20 days later 396 97
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