Don C. Adams, Richard T. Clark, Patrick E. Reece, and Jerry D. Volesky. Approximate stocking ... Nebraska-Lincoln Gudmundsen Sandhil/s Laboratory (GSL).
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RANGELANDS 20(5), October1998
Research and education for managing resources within the Nebraska Sandhills: The Gudmundsen Sandhills Laboratory Don C. Adams, Richard T. Clark, PatrickE. Reece, and Jerry D. Volesky
T
he Nebraska Sandhills which encompass
The Gudmundsen Sandhills Laboratory contains about about 12.75 million acres of rangeland are home for about 1,200 acres of subirrigated and wetland meadows and 535,500 head of beef cows. Located in the heart of 11,600 acres of upland sandhills range which include the Sandhills in Grant, sands, sandy and chopHooker and Cherry N E B R A S KA py sands range sites. Counties is the UniApproximate stocking rates for upland range versity of NebraskaLincoln's Gudmundsen and subirrigated meadSandhills Laboratory (GSL) formerly known as the "Rafter 'C' Ranch" (Fig. 1). The "Rafter 'C' Ranch," a 12,817 acre working ranch, was given to the University of Nebraska Foundation in 1978 by Elmer "Pete" and Abbie
ow are 0.5 and 3.5
AUM/acre, respectively. Hay is harvested from
meadows for winter feeding and to supplement dormant-season grazing on upland range sites. The dominant grass species on upland range sites are: little
Gudmundsen. Their bluestem [Andropogon desired purpose was Fig 1. Map of the Nebraska Sandhills and location of the University of scoparius (Michx.) stated, "to improve, ad- Nebraska-LincolnGudmundsenSandhil/sLaboratory (GSL). Figure provided Nash], prairie sandreed vance and support by the UniversityofNebraska-LincolnConse,vationandSuivey Division. [Calamovilfa longifolia agriculture in the state of Nebraska in ways that have rele- (Hook.) Scribn.], sand bluestem (Andropogon hal/li Hack.), vance to the Sandhills area of the state through added re- switchgrass (Panicum virgatum L.), sand lovegrass search, improved teaching and continuing education and [Eragrostis trichoides ( Nutt .) Wood], and blue grama service to the agricultural in[Boute/ouagrad//is ( H.K.B.) dustry." The University of Lag. Ex Griffiths]. Soils are Nebraska-Lincolnbecame predominantlyValentine fine the lessee of the sands (mixed, mesic Typic Gudmundsen Sandhills Ustipsamments).While forbs and shrubs generally acLaboratory from the Foundation in 1981. The count for less than 15% of "Rafter 'C" has made the the herbage, a great diversitransition from a commercial ty of forb species are widely ranch to a multi-disciplinary distributed on upland range research laboratory with additional fencing, water development, cattle handlingfacilities and roads. Research opportunity was enhanced with dormitory facilitiesfor
sites. Meadow soils are pri-
manly Gannett-Loup fine sandy loam (course-loamy mixed mesic Typic Haplaquoll). At GSL, differences in
to the water
table and depth Headquartersofthe GudmundsenSandhills Laboratory. students and faculty, a duration of standingwater inmeeting room, and a labofluerice the degree of soil ratory equipped for processing plant, insect, soil, water and wetness and the distribution of plant communities on the livestock diet and extrusasamples. meadow. Wetland sites have the longest duration of inun-
IRANGELANDS20(5), October1998
dation and tend to be dominated by sedges and rushes. The water table may be as deep as 5 feet during the grazing season on subirrigated sites which are dominated by grasses. Wet subirrigated sites have a degree of wetness and species composition that is intermediate between the wetland and subirrigated sites. Common species found in most meadows include smooth bromegrass (Bromus inermis Leyss.), redtop bent (Agrostis stolonifera L.),
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ulty with research at GSL, an extension educator, and the director of the Universityof Nebraska-Lincoln West Central Research and Extension Center in North Platte. One of the faculty researchersserves as the coordinator between the planning committee and the resident manager and supervises the resident manager. An industry advisory committee was formed in February 1996. The committee reviews research and education programming at GSL and
timothy (Phleum prat-
identifies research and
ense L.), slender wheatgrass [Elymus trachycaulum (Link) Gould ex
the beef cattle industry in the Nebraska
Shinn.], quackgrass [Elytrigia repens (L.) Nevski.], Kentuckybluegrass (Poa pratensis L.),
prairie cordgrass (Spartina pectinata Link), reedgrasses (Calamagrostis spp.), and numerous
species of sedges (Carexspp.and Cyperus
spp.), rushes (Scirpus spp.), and spikerushes (Eleocharis spp.). Big
education needs for Sandhills. Nominations —
for the committeewere made by the Nebraska CattlemenAssociation,
Sandhills Cattlemen the Association, Nebraska Section of the Society for Range Management,the Nebraska Branch of Holistic Management, and University of Nebraska faculty. The
advisory committee bluestem (Andropogon June calving cows with calves grazing Sandhillssummer range. represents an array of gerardii Vitman), indianranch sizes and the grass [Sorghastrum nutans (L.) Nash], and switchgrass full of the Sandhills.All advisorycommittee geographic region (Panicum virgatumL.) are present on most of the meadows members help withtechnologytransferto the industry. at GSL, but their relative abundance is low in areas that have historically been hayed each summer. Legumes and other forbs are generally minor components of meadow Researchand Education Objectives Our research and educational objectives focus on beef vegetation. The cow herd at GSL consists of about 360 March-calv- production systems from conception to slaughter. This ing and 200 June-calving cows. Cows are MARC II com- focus on systems allows us to identify necessary compoposites (1/4 Hereford, 1/4 Angus, 1/4 Simmental, and 1/4 nent research and then incorporate results into systems Gelbvieh). The herd was developed from 450 Angus X analysis. Research objectives are to develop plant/animal Hereford heifers which were purchased in the spring of systems that are economicallyand environmentallysustain1981 and 200 Angus X Simmental cows transferred from able. Our educationalobjective is to provide knowledgeand the Sandhills Ag Lab (closed in 1981) near Tryon, decision support systems including monitoring techniques Nebraska. Bulls are obtained from the USDA-ARS Meat for optimal and sustainable use of Sandhills rangeland reAnimal Research Center (MARC) near Clay Center, sources. Since the inception of GSL, research and educaNebraska. Fall pregnancy rate for March and June calving tional programs have become more ecologically diverse cows has generally been about 93% and calving rate has and team oriented. Joint projects with animal, range, soil, generally been about 98%. The culling rate of the cow herd veterinary, economics, entomology, geology, hydrology, has been highly variable to accommodate various heifer forestry and wildlife have increased our understanding of development studies. Heifers selected to replace cull cows the Sandhills ecosystem. Facility development, increasing are developed at GSL. Surplus heifer calves have been diversity of faculty expertise, cooperative efforts with other used in studies at other research locations in the University University of Nebraska centers and strong support of the of Nebraskasystem or sold at weaning if they are not need- beef cattle industry have all contributedto the researchand ed. Steer calves may be wintered and summer grazed at educationalefforts. GSL as yearlings, fed in University of Nebraska-Lincoln feedlots at Mead or Scottsbluff, or sold at weaning if they Past Researchat GSL are not needed for research. A number of studies at GSL have tested concepts which A resident manager supervises 3 full-time technicians have contributed to the developmentand evaluation of liveand directs day-to-day operations at GSL. Planningand co- stock production systems for the Sandhills (Ward 1997). ordination of research and education activities at GSL is Protein and energy supplements have been studied for drydone by a faculty planning committee comprised of all fac- gestating cows and lactating cows grazing dormant-season
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forage on upland range sites. Cows have generally re-
sponded more favorably to supplemental protein than energy during fall-winter grazing. Dry-gestating cows grazing winter range generally loose body condition without supplemental protein. Gestating cows grazing winter range will maintain body conditionwith a small amount of supplemental degraded intake protein (DIP, i.e. rumen degradable protein). The requirement for supplemental rumen degrad-
RANGELANDS 20(5), October 1998
We recognizedthat if we were to be effective in development and evaluation of livestock production systems we needed a greater understandingof seasonalpatterns in diet quality and composition on meadows and upland range, particularlywhen reducingfed forages and relying more ex-
able protein is likely between 0.31 and 0.37 lb/day (Hollingsworth-Jenkinset al. 1996). Lactating cows grazing
fall-winter range have responded to both degraded intake protein and undegraded intake protein (UIP , escape protein). Second-cuttinghay, harvested on subirrigated meadows in August after a first cutting in June, contained about 15% crude protein and was as effective as more expensive soybean meal supplements in maintaining body condition of dry-gestating cows grazing winter range. Weaning March-born calves in early September improved condition score of cows in November over cows that suckled calves until November. Gain of calves weaned in September and placed on subirrigatedmeadow regrowthafter a first cutting of hay in July was equal to calves suckling cows on upland range during the September to November period (Lamb et al. 1997). March- and April-born calves, suckling cows on upland range during summer (Hollingsworth-Jenkins1994) or on subirrigated meadow regrowth in the fall (Lardy 1997), have increased gains when supplementedwith UIP over non-supplemented calves, suggesting that protein available for growth is limiting calf gain.
MARC IIcows on winterrangecomingto be fed proteinsupplement.
The first systems research at GSL addressed winter and post-calving grazing and feeding within year-long production cycles for March-calving cows (Adams et al. 1994). This work showed that extending winter grazing and grazing cool-seasonforages on subirrigated meadows in early spring, in lieu of feeding hay, increased returns per calf up to $90/head. Systems which fed the least hay were consistently most profitable.
MARC II cows eating protein supplement.
tensivelyon grazed forages. Nutrient contentof hay, individual plant species, and livestock diets from both meadows and upland range have been described in relationship to plant maturity in agronomic meadow studies, tiller staging and grazing preferencestudies on uplandsites, and by diets from fistulated cows and calves. Agronomic studieson subirrigated and wetland meadows have evaluated harvest date, fertilizer, and harvest date by date of fertilizationinteraction effects on yield and quality of hayand regrowthafter haying, plant recovery of applied nutrients, and species composition. Economic analysis of the yield and forage quality of hay showed that application of nitrogen, sulphur, and phosphorusto subirrigatedmeadows can be profitable practices, especially when accounting for forage quality. When forage quality was valued as part of this economic analysis of meadowforage, optimal harvesttime was earlier than traditionalhaying dates in the area (Norton et al. 1997). Nutritional knowledge gained from meadow research at GSL has been critical for extending the length of grazing seasons, consistently producing high quality forages for supplements and heifer development, and increasing flexibility in calf and yearlinggrazing programs. In order to utilize the metabolizableprotein system adopted by the National Research Council (NRC 1996), degraded intake protein (DIP), undegraded intake protein ( UIP and forage digestibilityhave been determined on diet samples collected throughout the year from upland range and subirrigatedmeadows (Lardy et al. 1998). Nutrient intake is the product of concentration of a nutrient in a forage and the amount of forage consumed.Considerableefforts were made to build a base of forage intake data for cows throughout the year at all stages of pregnancy and lactation, and for weaned and suckling calves and yearlings. With regression models (Lardy et al. 1998) of annual pro-
RANGELANDS 20(5),October1998
7
tein and digestibility patterns and reliable estimates of for- reductionsin root length in plants clipped to simulate grazage intake components, the metabolizable protein system ing (Engel et al. 1997). Root response to grazing has beand energy can be evaluated for a variety of animal re- come an important area of our research. Infiltration rates quirements to determine first limiting nutrients or deficien- are high and water holding capacity is low in the sandy cies. These evaluations can then be the basis for nutrition soils of this ecosystem. and management research needed for developing and reUtilization of prairie sandreed during early summer is fining livestock production systems. highly correlated with grazing pressure and percent of prairie sandreed tillers grazed is highly correlated with use. Grazing pressures can be calculated for many grazing schemes, based on our documentationof seasonal distribution of current-year herbage, and used to predict use of this key forage species. Four years of heavy summer stocking rates on sands range sites increasedthe species composition of cool-season grasses by 10 percentage points, from 5% to 15%. Heavy grazing also caused measurable increases in western ragweed (Ambrosiapsilostachya Dc.) which declinedto pretreatment levels after 1 year of rest. Grazing treatments
in several studies at GSL have caused measurable changesin foliar architectureand insect populationsthat af-
A forage yieldandqualityploton a subirrigatedmeadowat GSL. The large geographic area of the Sandhills and the diversity of enterprises and managerial thought processes have resulted in a wide variety of grazing strategies. It became
fect distribution and decompositionof litter. Changes in foliar architecturealso affect wildlife habitat. Grazing pastures only in June or July at light stocking rates resulted in adequate cover for prairie grouse nesting sites in the following year. Moderate stocking in June frequently provided ade-
quate cover while heavy grazing in either month resulted in poorcover for sharp-tailed grouse (Pedioecetesphasianellus) or prairie chickens (Tympanuchuscupido).
evident that in the Nebraska Sandhills,testimonials and not reliable data were generally the norm for evaluating im- Presentand Future Research pacts of proposed grazing schemes on meadows and upAt GSL we are trying to determine effects of cattle on land range. Resourceswere not available at GSL for comrangeland resourcesand vice versa over full production cyparative studies of all possible grazing schemes on upland cles. Profitabilityand sustainabilityof the range and/or meadows. Additionally, we resource rather than selected production found considerable controversy among will be the criteria for evaluating outputs ranchers and conservationists about imsystems. Key to our present work is a pacts and interpretation of studies and of cooperationamong faculty degree high grazing systems implemented in other from Animal Science, Range Science, geographic locations. The approach conAgricultural Economics, Entomology, ceived for studying grazing effects on upVeterinary Science, Water Conservation, land range and subirrigated and wetland and Nebraskaforestry and input from the meadows needed to be well controlled, beef industry, the primary user of replicated and have broad application. Sandhills forage resources. These needs led to the developmentof a Based on our work with March-calving series of grazing studies designed to procows we hypothesized that if the cows' vide a broad ecological data base for the lactation and calving date were matched developmentof grazing systems that are with nutrients available in upland range designed to achieve specific resource and meadow forages, that ted hay could management and livestock production be reduced by a ton or more. We further A steer fit with a fecalcollection bag objectives. hypothesized that the improved match for intake studies. Short-durationgrazingtreatments were would enhance profitability of Sandhills used to simulate arrays of grazing strategies in large sets of ranches the amount of hay fed and labor and by reducing small upland range pastures. The treatments evaluated re- equipment associated with feeding. Simple descriptive source responsesto date and frequency of grazing, date by models of the nutrients in range and meadow forages prostocking rate interactions, and grazing pressure (Ward vided the basis to conceptually match the cows' nutrient re1997). Prairie sandreed was more susceptible to heavy quirementswith nutrients in grazed forages. To test our hygrazing during June—August than sand bluestem.Cattle se- pothesis, we selected a mid-June calving date as a means lectively grazed both species all summer (Reece et al. to match the nutrient requirementsof late gestation and lac1996). Reductionsin total organic reserves of grazed sand tation with a high concentrationof protein and digestibilityin bluestem populations corresponded to similar percentage range forages. In this study, the endpoints for evaluation
RANGELANDS 20(5), October1998
8 are returns per cow exposedto the bull at weaning, and the returns on the calf through to slaughter. All production outputs and costs are recorded for the traditional March-calving cow herd and the June-calving herd. All marketing opportunities will be evaluated. A progress evaluation after 3 years (Clark et al.1997) showed that annual fed forage has been reduced by over 3,000 lb/cow with the June-calving system and returns per calf are about $50 greater for Juneborn than March-bornsteer calves. Replacing days on harvested feed with grazing days will requireknowledgeof how combined seasonsof grazing during spring, summer, and/or dormant seasons affect rangeland resourcescompared to single seasons of use. We hypothesize that sustainable stocking rates on upland range sites will increaseas the percentageof annual stocking rate is shifted from summer to dormant-seasongrazing. Recently initiated studies will focus on different systems of managing
growing cattle from weaning to finishing with different schemes for backgrounding weaned calves and summer grazing yearlings on different combinationsof meadow and upland range before shipment to feedlots.These studies will involvedetailed ecologicaland economicassessment.
Literature Cited Adams, D.C., R.T. Clark, S.A. Coady, J.B. Lamb, and M.K. Nielsen. 1994. Extended grazing systems for improving eco-
nomic returns trom Nebraska Sandhills cow/calf operations. J. Range Manage. 47:258—263. Clark, R.T., D.C. Adams, G.P. Lardy, and T.J. Klopfenstein. 1997. Matching calving date with forage nutrients: Production and economic impacts. Proc. The Range Beef Cow Symposium XV. Dec. 9—11, 1997. Rapid City, S. Dak. Engel, R.K., J.T. Nichols, J.L. Dodd, and J.E. Brummer. 1997. Root and shoot responses of sand bluestem to defoliation. J. Range Manage.51:42—46. Holllngsworth-Jenkins, K.J. 1994. Escape protein, rumen degradable protein, or energy as the first limiting nutrient of nursing calves grazing Sandhills range. Ph.D. Diss. Univ. Nebr.Lincoln, Lincoln, Nebr. Hollingsworth-Jenkins,K.J., T.J. Klopfenstein, D.C. Adams, and J.B. Lamb. 1996. Ruminally degradable protein requirement of gestating beef cows grazing native winter Sandhills range. J. Anim. Sd. 74:1343—1348. Lamb, J.B., D.C. Adams,T.J. Klopfenstein, W.W. Stroup, and G.P. Lardy. 1997. Range or meadow regrowth and weaning effectson 2-year-oldcows. J. Range Manage. 50:16—1 9.
Lardy, G.P. 1997. Protein supplementation of calves and cows grazing Sandhills range and subirrigatedmeadow. Ph.D. Diss., Univ. Nebr.-Lincoln.Lincoln, Nebr. Lardy, GD. Adams,T. Klopfenstein,and D. Brink. 1998. Use of the NRC model for evaluating nutrient balances of grazing beet cattle. p. 7-11 In: Beef Cattle Report University NebraskaLincoln. MP 69-A. Norton,N.A., R.T. Clark, P.E. Reece, and K.M. Eskridge. 1997. Quality as a factor in the optimal choice of fertilization and harvest date of meadow hay. J. Prod. Agr. 10:551—557 and 509—510.
NRC. 1996. Nutrient requirements of beef cattle, seventh revised
edition. National Research Council. Nat. Acad. Press. Washington,D.C.
Reece, P.E., J.E. Brummer, R.K. Engel, B.K.Northup, and J.T. Nichols. 1996. Grazing date and frequency effects on prairie
sandreed and sand bluestem.J. Range Manage. 49:112—116. Ward, J.K. 1997. Forage utilization by beef cattle. Nebraska research 1960-1996. Univ. Nebr.-Lincoln Center for Grassland Studies and Agr. Res. Div. Lincoln, Nebr. PubI.RB325.
Adams, Clark, and Voleskyare faculty at the Universityof Nebraska, West Central Reseach and Extension Center, Rt. 4 Box 46A, North Platte, Neb. 69101. Reece is faculty at the University of Nebraska, PanhandleResearch and ExtensionCenter,Scottsbluff, Nebr. Published with the approval of the Director of the University of Nebraska-Lincoln Institute of Agriculture and Natural Resources, AgricultureResearch Division asJournal Series No. 12142.
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