Dormant Season (Winter) Grazing Management
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Transcript of Dormant Season (Winter) Grazing Management
Dormant Season (Winter) Dormant Season (Winter) Grazing ManagementGrazing Management
Kevin K. SedivecKevin K. Sedivec
Extension Rangeland SpecialistExtension Rangeland Specialist
North Dakota State UniversityNorth Dakota State University
Why Concerns with Winter Grazing Why Concerns with Winter Grazing and Nutrient Management?and Nutrient Management?
The longer your on The longer your on pasture, the more pasture, the more NATURAL manure is NATURAL manure is being managedbeing managed
Reduces manure Reduces manure management within management within the lot/yardsthe lot/yards
Reduces Reduces confinement in confinement in small areassmall areas
Why Winter Graze?Why Winter Graze?
Winter feed costs total up to $200 per animal unit per Winter feed costs total up to $200 per animal unit per year.year.
Potential for economic benefit/better utilize of the Potential for economic benefit/better utilize of the range resourcerange resource
Practiced by many western Dakota, Montana and Practiced by many western Dakota, Montana and Wyoming ranchersWyoming ranchers
Little information regarding ecological effects in Little information regarding ecological effects in Northern PlainsNorthern Plains
Effect of Winter Defoliation on Effect of Winter Defoliation on Herbage ProductionHerbage Production
Cool-season grasses maintain green Cool-season grasses maintain green leaves throughout the dormant season leaves throughout the dormant season (Baron 2002)(Baron 2002)
Much of the available literature Much of the available literature regarding winter survival of plants from regarding winter survival of plants from an agricultural perspective has been an agricultural perspective has been concentrated on tame forage pastures concentrated on tame forage pastures and meadowsand meadows
Effect of Winter Defoliation on Effect of Winter Defoliation on Cool and Warm Season GrassesCool and Warm Season Grasses
Freeze et al. (1999) showed lifetime Freeze et al. (1999) showed lifetime productivity of fescue grasslands in Alberta, productivity of fescue grasslands in Alberta, Canada was enhanced by winter grazing as Canada was enhanced by winter grazing as opposed to summer grazingopposed to summer grazing
Reisterer et al. (2000) found winter Reisterer et al. (2000) found winter defoliation on tame cool season grasses in defoliation on tame cool season grasses in southern Minnesota was not different from southern Minnesota was not different from the ungrazed controlthe ungrazed control
Effect of Winter Defoliation on Effect of Winter Defoliation on Cool and Warm Season GrassesCool and Warm Season Grasses
Schacht et al. (1998) in Nebraska, Auen Schacht et al. (1998) in Nebraska, Auen and Owensby (1988) in Kansas, and and Owensby (1988) in Kansas, and Engel et al. (1998) in Oklahoma found Engel et al. (1998) in Oklahoma found winter defoliation of selected warm-winter defoliation of selected warm-season grasses was not detrimental to season grasses was not detrimental to herbage productionherbage production
Greatest Negatives to Winter Greatest Negatives to Winter GrazingGrazing
Seasonal Forage Seasonal Forage LossLoss Herbage production Herbage production
peaks in June and peaks in June and JulyJuly
Natural loss of Natural loss of standing crop occurs standing crop occurs after peakafter peak
Seasonal Nutritional Seasonal Nutritional LossLoss Crude protein and Crude protein and
TDN decline and TDN decline and fiber increase with fiber increase with maturationmaturation
Most minerals also Most minerals also decline with decline with maturationmaturation
Seasonal Herbage Production Seasonal Herbage Production (ND & SD) in 2004-2005(ND & SD) in 2004-2005
200
500
800
1100
1400
1700
May July Sept. Nov. Jan. Mar/April
Silty
Shallow
Seasonal Growth Rates of Native Seasonal Growth Rates of Native GrassesGrasses
0102030405060708090
100
Apr.26
May.15
Jun.1
Jul.1
Jul.25
Aug.22
Sept.14
Oct.5
Nov.10
WesternwheatgrassGreenneedlegrassBlue grama
Prairie Sandreed
Crude Protein (%) Content of Crude Protein (%) Content of Select Cool-season GrassesSelect Cool-season Grasses
0
5
10
15
20
25
30
2.5
lf3.
5 lf
4.5
lfBoot
Seed H
ard
Jul.
25
Sept.
15
Basin Wi.
Slender Wh.
Bluebunch Wh.
Russian Wi. Boz
Bluebunch/Quack
Smooth Br.-Rebound
Inter. Wh
Crested Wh.-Ephr
Pube. Wh. Manska
Crested Wh.-Nordan
Green Needle
Tall Wheat.
Altai Wi.
Meadow Br.
Min. Req. Lact. Cow
SMOOTH BROMEGRASSSMOOTH BROMEGRASS – Seasonal – Seasonal growth pattern and crude proteingrowth pattern and crude protein
0
5
10
15
20
25
May.1
May.15
June.1
July.1
July.21
Aug.15
Sept.10
Oct.1
0102030405060708090100
Crude Protein% Growth
Winter Grazing Trial in Western Winter Grazing Trial in Western North and South Dakota: 1999-2006North and South Dakota: 1999-2006
Adams CountyAdams County
Perkins CountyPerkins County
Treatments (4)Treatments (4)
Winter grazing (15 November-10 January) @ 50% Winter grazing (15 November-10 January) @ 50% disappearance of above ground biomass disappearance of above ground biomass (Full Use)(Full Use) No summer grazingNo summer grazing
Winter grazing @ 30% disappearance Winter grazing @ 30% disappearance (Moderate)(Moderate) No summer grazingNo summer grazing
Summer grazing (June 5-15) @ 25% disappearance Summer grazing (June 5-15) @ 25% disappearance (Flash(Flash grazing) + Winter grazing @ 50% disappearance grazing) + Winter grazing @ 50% disappearance (Full Use)(Full Use)
Season-long, summer-only grazing @ 50% Season-long, summer-only grazing @ 50% disappearance disappearance (Control)(Control)
Peak Herbage Production Peak Herbage Production 20012001
0200400600800
100012001400160018002000
SL FL DS30 DS50
Kg
/ha
P>0.05 P>0.05 “NS”“NS”
TreatmenTreatmentt
Peak Herbage Production Peak Herbage Production 20022002
0
100
200
300
400
500
600
700
800
SL FL DS30 DS50
a
b
ab
b
Kg
/ha
P<0.05P<0.05TreatmeTreatmentnt
0
200
400
600
800
1000
1200
SL FL DS30 DS50
Peak Herbage Production Peak Herbage Production 20042004
aab
bab
P<0.05P<0.05TreatmenTreatmentt
Kg
/ha
0
500
1000
1500
2000
2500
SL FL DS30 DS50
Peak Herbage Production Peak Herbage Production 20052005
aa
ab
b
P<0.05P<0.05TreatmenTreatmentt
Kg
/ha
Plant species compositional Plant species compositional changes since 2000changes since 2000
To date: NO SIGNIFICANT differences To date: NO SIGNIFICANT differences in plant species diversity and richness in plant species diversity and richness have occurred on either treatmentshave occurred on either treatments
This is a LONG-TERM question that This is a LONG-TERM question that usually takes 5 to 10 years to see usually takes 5 to 10 years to see differences (if they occur)differences (if they occur)
0
5
10
15
20
25
30
35
2001 2002 2003 2004 2005
SLFL30%50%
Western Wheatgrass (July) Western Wheatgrass (July) 2001-20052001-2005
P<0.05
stt
s
xx
y z
Heig
ht
(cm
)
YearYear
bac
abcc
fg f fg
mmm
m
0
2
4
6
8
10
12
2001 2002 2003 2004 2005
SL
FL
30%
50%
Blue grama (August)Blue grama (August)2001-20052001-2005
P<0.05
wzx
y z
Heig
ht
(cm
)
YearYear
a aba
fgfg g
mmmm
st t
u
Swath Grazing Study in south Swath Grazing Study in south central North Dakota - 2005central North Dakota - 2005
Treatments (4)Treatments (4) Swath grazing foxtail millet (annual warm season) Swath grazing foxtail millet (annual warm season)
Swathed mid September, grazed October 15 – December 15Swathed mid September, grazed October 15 – December 15
Swath grazing crested wheatgrass/legume (perennial Swath grazing crested wheatgrass/legume (perennial cool season) cool season) Swathed mid September, grazed October 15 – December 15Swathed mid September, grazed October 15 – December 15
Swath grazing big bluestem (perennial warm season) Swath grazing big bluestem (perennial warm season) Swathed mid September, grazed October 15 – December 15 Swathed mid September, grazed October 15 – December 15
with a 33 % protein supplement cake (2 lbs/d)with a 33 % protein supplement cake (2 lbs/d)
Dormant season grazing Dormant season grazing Grazed October 15 – December 15Grazed October 15 – December 15
Initial and final body condition on Initial and final body condition on dry cows grazing swath treatments dry cows grazing swath treatments
and native range in 2005and native range in 2005
4
4.5
5
5.5
6
FoxtailMillet
CrestedWheat
Big Blue NativeRange
15-Oct
15-Dec
**
* Cattle on the big bluestem treatment were supplement with 2 lb/d * Cattle on the big bluestem treatment were supplement with 2 lb/d
33 % protein block33 % protein block
Initial and Final weight of cows grazing Initial and Final weight of cows grazing swath treatments and native range in swath treatments and native range in
20052005
1100
1150
1200
1250
1300
FoxtailMillet
CrestedWheat
Big Blue NativeRange
15-Oct
15-Dec
**
* Cattle on the big bluestem treatment were supplement with 2 lb/d * Cattle on the big bluestem treatment were supplement with 2 lb/d
33 % protein block33 % protein block
Importance to Extending the Importance to Extending the Grazing SeasonGrazing Season
Allows for natural spreading of manure Allows for natural spreading of manure and urine, and adding a degradable and urine, and adding a degradable nutrient into the ecosytemnutrient into the ecosytem
Reduces labor and costs of harvested Reduces labor and costs of harvested feedsfeeds
Also, reduces the efficiency of Also, reduces the efficiency of harvesting forage produced and harvesting forage produced and nutritional status of the feednutritional status of the feed
ConclusionsConclusions
Winter grazing has potential for Winter grazing has potential for economic benefit to ranchers on the economic benefit to ranchers on the Northern Great PlainsNorthern Great Plains
Winter grazing strategies lengthen the Winter grazing strategies lengthen the grazing season/shorten the winter-grazing season/shorten the winter-feeding periodfeeding period
Any Questions?Any Questions?