North Dakota State University * Dickinson Research Extension Center
1133 State Avenue, Dickinson, ND 58601 Voice: (701) 483-2348 FAX: (701) 483-2005
GRAZING ANNUAL FORAGES
- Preliminary Observations -
(Presented at the NDSU Cow/Calf Conference in Bismarck, December 5, 1998)
W.W. Poland, P.M. Carr and L.J. Tisor
Portions of this material is based upon work supported by the
Cooperative State Research, Education, and Extension Service, U.S. Department of
Agriculture, under Agreement No. 96-34216-2539
Research has demonstrated that barley, oat, pea and Siberian millet can be used to provide productive annual pastures when grazed singularly or in sequence during the summer in the Northern Great Plains.
Beef cattle have grazed annual forages at the Dickinson Research Extension Center for 5 yr (4 yr with cow/calf pairs; 1 yr with bred heifers). Stocking rate (animal unit/mo; AUM) and animal performance varied from year to year and crop to crop. Seasonal stocking rate averaged .8 AUM/ac; individual animal performance averaged 2.5 lb/d for suckling calves and 2.0 lb/d for bred heifers; and live weight gain averaged 66 lb/ac. Although the potential for grazing cattle on annual forages is quite promising, further research is needed to identify promising forage species for grazing and establish potential forage sequences and optimal seeding dates, initial grazing dates, stocking rates, and grazing management appropriate for annual forage pastures.
Prices received for agricultural commodities are often low compared to the relatively high costs of production. This results in relatively low net returns per acre for the amount of capital invested. At the same time, a reduction in government control of agricultural production has given producers greater flexibility in developing their own farming plans. As these producers contemplate new cropping decisions, crop rotations involving annual forages are gaining in popularity. Annual forages have potential for increasing net returns to crop acres by providing feed for livestock production. Forages can be harvested and fed or grazed in the field. Studies have been initiated to evaluate the potential of using traditional crop land for cattle production by growing sequences of annual forage and grazing beef cattle during the summer.
Materials and Methods
In each of 4 yr, crossbred cow/calf pairs (animal unit [AU]=cow/calf pair) grazed on sequences of annual forages. Eight paddocks (8.3 ac/paddock) were arranged into two, 4-pasture blocks. Within each block, annual forages were randomly seeded (Table 1) into individual paddocks and grazed sequentially with a constant stocking rate (2.05, 1.45, 1.2 and 1.2 AU/ac in 1993, 1994, 1995 and 1996, respectively). Annual forages selected for grazing evaluation included: winter rye, cereal/pea intercrop, and millets (Siberian and Pearl). Use of Pearl millet was discontinued in 1994 due to agronomic difficulties and replaced by barley in 1995 and 1996. Within each year, the desired grazing management involved grazing rye in May, cereal/pea in June, Pearl millet or barley in July and Siberian millet in August. Calves were weighed at the initiation and termination of grazing in each pasture. Average daily gain, gain per acre and accumulated grazing days (AUM/ac) were used to evaluate the grazing potential of each forage type. A complete description of grazing evaluations between 1993-1994 and 1995-1996 is given in Manske and Nelson (1996) and Poland et al. (1996), respectively.
In 1998, 12 paddocks (2.5 ac/paddock) were blocked into two, 6-paddock groups (2 paddocks/forage type). One group was seeded to pea, oat or oat-pea intercrop, while the other group was seeded to lentil, barley or barley-lentil intercrop. Paddocks were grazed by bred beef heifers (.75 AU/heifer) at a constant stocking rate of .9 AU/ac. Paddocks seeded (Table 1) to oat, pea and oat/pea combinations were grazed first (mid June to mid July), followed by paddocks seeded to the barley, lentil and barley/lentil combinations (mid July to mid August). Grazing potential of each forage type was evaluated as in earlier experiments. This seeding/grazing sequence will be repeated in a second set of paddocks in 1999. A more detailed description of the 1998 grazing evaluation is given in Poland et al. (1998).
Results and Discussion
Seeding and grazing dates and accumulated grazing days per acre are presented in Table 1. With the exception of 1993, all paddocks were grazed between 15 May and 31 August. Under the grazing management imposed, sequences of annual forages accumulated an average of .82 AUM/ac. A hypothetical, 640-ac pasture seeded to an appropriate sequence of annual forages would be expected to support 150 animal units for 3.5 mo (approximately 15 May - 31 August).
Suckling calf performance (4 years; 1993 - 1996) is summarized in Table 2. Although there was considerable variation within forage types both among and between years, annual performance averaged 2.48 lb/head/d and 66.0 lb/ac. The 150-cow herd in the previous example would be expected to add 260 to 280 lb per calf over the summer period (3.5 mo). A calf with a 65 lb birth weight that had gained 120 lb (60 days of age gaining at 2.0 lb/d) prior to moving to annual forage pastures would weigh approximately 455 lb (65+120+270) by the end of August.
Bred heifer performance (1 year; 1998) is also presented in Table 2. Heifers averaged 2.0 lb/d from mid June to mid August. Heifer live weight gain per acre (67.2 lb/ac) was comparable to average suckling calf performance reported in previous years.
Five years of research demonstrates that beef cattle can successfully graze annual forages in the Northern Great Plains during the summer. Seasonal stocking rates have averaged .8 AUM/ac, while live weight gain per acre has averaged 66 lb. Individual daily gain has averaged 2.5 lb for suckling calves and 2.0 lb for bred heifers. Data from specific forage types suggests that seasonal production parameters can be improved. New research is needed to support the development of optimally matched annual forage production and grazing strategies.
Manske, L. and J. Nelson. 1995. Grazing annual forage pastures. 43rd Annual Research Roundup. Dickinson Res. Ext. Center, North Dakota State University. pp16-39. (http://www.ag.ndsu.nodak.edu/dickinso/research/1995/grass95c.htm/).
Poland, C., L. Tisor, P. Carr and L. Manske. 1997. Grazing annual forages in the Northern Great Plains. 46th Annual Research Roundup. Dickinson Res. Ext. Center, North Dakota State University. pp46-56. (http://www.ag.ndsu.nodak.edu/dickinso/research/1996/grazforg.htm).
Poland, W.W., P.M. Carr, L.J. Tisor and G.O. Ottmar, 1998. Grazing cereal and cereal-pulse intercrops in southwestern North Dakota. 1998 Annual Report, Dickinson Res. Ext. Center, North Dakota State University. ppxx-xx. (http://www.ag.ndsu.nodak.edu/dickinso/research/1998/range98o.htm).
|Table 1. Seeding and grazing dates and stocking rates for beef cattle grazing annual forages at Dickinson Research Extension Center.|
|Year/Forage Type||Seeding date||Grazing dates||Days||AUMa/acre|
|1993b||01June - 30September||57||.96|
|OP intercropc||24April||13July - 27July||14||.94|
|Pearl millet||Early May||not grazed||--||--|
|Siberian millet||Early June||01September - 15September
08October - 14October
|Pearl millet||Mid July||15September - 08October||23||1.54|
|1994||01June - 30September||67||.79|
|Winter rye||August, 1993||15June - 13July||27||.64|
|OP intercrop||07May||14July - 08August||26||1.23|
|Pearl milletd||not seeded||--||--||--|
|Siberian millet||Early June||23August - 06September||14||.66|
|1995||15May - 31August||77||.76|
|Winter rye||August, 1993||15May - 30May||15||.59|
|CP intercropc||03May||29June - 26July||27||1.07|
|Barleyd||01June||27July - 11August||16||.62|
|Siberian Millet||12June||12August - 30August||19||.75|
|1996||15May - 31August||68||.67|
|Winter rye||May, 1995||28May - 10June||13||.52|
|CP intercrop||20April||14June - 01July||17||.68|
|Barley||24May||16July - 06August||21||.83|
|Siberian Millet||29June||07August - 23August||17||.68|
|1998||15June - 15August||61||.92|
|Oat and Pea||27April||15June - 20July||35||1.05|
|Barley and Lentil||04June||22July - 17August||26||.78|
|a Animal unit month or the equivalent of
one cow-calf pair grazing for one month. Bred heifer were considered to be .75 animal
b Stocking rates were 2.05, 1.45, 1.2, 1.2 and .9 animal units per acre in 1993, 1994, 1995, 1996 and 1998, respectively.
c OP and CP refer to oat-pea and oat-pea-winter rye intercrops, respectively.
d Use of Pearl millet discontinued in 1994 and was replaced by barley in 1995 and 1996.
|Table 2. Cattle performance while grazing annual forages at Dickinson Research Extension Center.|
|Year/Forage Type||Average daily gain
|SEa||Gain per acre
|Suckling calf performance|
|Overall for forage typef|
Bred heifer performance
|Oat and Pea||1.45||.18g||61.4||5.8g|
|Barley and Lentil||2.62||.18g||73.0||5.8g|
|a Standard error of mean.
b Stocking rates were 2.05, 1.45, 1.2, 1.2 and .9 animal units per acre in 1993, 1994, 1995, 1996 and 1998, respectively. One animal unit equating to a cow-calf pair or 1.2 bred heifers.
c Not applicable or not reported.
d OP, CP and BL refer to oat-pea, oat-pea-winter rye and barley-lentil intercrops, respectively.
e Use of Pearl millet was discontinued in 1994 and replaced by barley in 1995 and 1996.
f Means are averaged across years (winter rye, n=3; OP/CP intercrop and Siberian millet, n=4; Pearl millet, n=1; barley, n=2).
g Standard error is average for all forage types within year.