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?