ASSESSING THE POTENTIAL OF CO-GRAZING SMALL RUMINANTS WITH BEEF CATTLE TO IMPROVE UTILIZATION OF MARGINAL PASTURELANDS IN VIRGINIA.

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1 ASSESSING THE POTENTIAL OF CO-GRAZING SMALL RUMINANTS WITH BEEF CATTLE TO IMPROVE UTILIZATION OF MARGINAL PASTURELANDS IN VIRGINIA D. M. We 1, Ozzie Aye 1, Jon Rockett 2, Crl Zipper 1, C. Teutsch, nd G. Scgli 3 1 Crop nd Soil Environmentl Sciences, Virgini Tech, Blcksurg, VA 24061; 2 Powell River Project nd Virgini Coopertive Extension, Wise County, Virgini; 3 Animl nd Poultry Sciences, Virgini Tech, Blcksurg, VA Astrct Reclmtion efforts in the Applchin col field region hve successfully resulted in res tht re suitle for livestock enterprises. Often these res re underutilized due to incresing infesttion y invsive species tht reduce psture utiliztion y cttle. The steep topogrphy nd low economic returns from cttle mke invsive vegettion control y mechnicl or chemicl mens unvile. Gots my e n economiclly vile lterntive for improving utiliztion of these mrginl lnds. Gots select diet minly of rowse nd re considered n idel species for mixed grzing with cttle. In spring 2006, n experiment ws initited t Powell River Project ner Wise, VA, to compre the effects of co-grzing cttle nd gots, cttle lone, nd n ungrzed control on forge mss nd otnicl composition. Experimentl design ws completely rndomized design with three replictions for the grzed tretments nd two replictions for the ungrzed control. Initil results indicted greter psture utiliztion for the co-grzed tretment. The weed component of the swrd ws lower in oth co-grzed nd cttle tretments (14.5% nd 16.0% respectively) compred to the ungrzed control (44.4%) y the end of the grzing seson. These initil dt indicte tht co-grzing gots nd cttle could help to chieve nd mintin desirle lnce of herceous nd shru species tht re desirle for co-grzing nd would increse the overll productivity of reclimed mined lnd pstures in the southestern United Sttes. Introduction: Although much of the lnd tht is creted y col-mining opertions is restored to condition tht is suitle for livestock grzing, these lnds re sometimes ndoned from grzing due to difficulty in controlling woody vegettion. The use of cogrzing systems to improve psture utiliztion tht is infested with undesirle species cn produce economic enefits for producers y enling expnsion of grzing ctivities to mrginl lndforms, which could not otherwise e fully utilized. This prctice tkes dvntge of different feeding hits etween grzing nimls tht my result in improved psture conditions for one or more livestock species. Incresed niml performnce nd output per lnd re re possile (Allen nd Collins, 2003). Gots re prticulrly useful in co-grzing systems with cttle. Gots prefer rowse nd weed species wheres cttle prefer grsses nd legumes (Bll et l., 2002). Likewise, the grzing hits of gots my reduce the need for chemicl or mechnicl vegettion control methods on steep hillsides. Reserch conducted in North Crolin hs shown tht mountin hillsides infested with multiflor rose (Ros multiflor L.,), lck locust (Roini pseudocci L.,), nd other undesirle vegettion cn ecome dominted y 1

2 grsses nd legumes within four yers of co-grzing gots with cttle (Luginuhl et l., 1999; 2000). In ddition, the demnd for got products hs incresed in recent yers (Glimp, 1995). The sustinle use of co-grzing gots with cttle could improve utiliztion of ville vegettion nd improve frm productivity in the col mining regions of Applchi. The ojective of this study is to compre the effects of co-grzing cttle nd gots, cttle lone, nd n ungrzed control on forge mss nd otnicl composition. Mterils nd Methods: In spring of 2006, n experiment ws initited t the Powell River Project in Wise, VA, to compre the co-grzing of gots with cttle vs. cttle only grzing on psture mss nd otnicl composition. Tretments included: n ungrzed control, cttle only, nd co-grzing. Experimentl design ws complete rndomized design with three replictions for the grzing tretments nd two replictions for the control. Three crossred steers (Bos turus) (verge BW = 648 l) were ssigned to ech grzing tretment, with the stocking rte (0.67 steers cre -1 ). Fifteen Spnish crossred ucks (Cpr hircus) (verge BW pproximtely = 46 l) were dded to the co-grzing tretment. Pstures were mnged under rottionl stocking. Pstures were grzed for two weeks nd rested for four weeks. All nimls were treted for internl prsites nd trce minerl slt ws provided free choice. Pstures were smpled three times (spring, summer, nd fll) during the grzing seson. Forge mss ws determined y clipping four, 2.69 ft² res per control tretment nd eight, 2.69 ft² res per grzing tretment. Prior to hrvesting, otnicl composition ws determined visully using the Doule DAFOR scle (Brodie, 1985; Aye et l., 1997). This scle rnks the reltive undnce of species where D=dominnt, A=undnt, F=frequent, O=occsionl, nd R=rre. There re two DAFOR scles, one for forges nd one for weeds. In ddition, percent ground cover, grss, legume, nd weed were visully estimted. Serice lespedez [Lespedez cunet (Dum.-Cours.) G. Don] ws considered weed in this experiment s it is not fvored y cttle during lrge prt of the yer due to its high tnnin content (Dove et l., 1997). All dt present ws sujected to the generl liner models procedure from SAS (SAS Institute, 1982). Fctors included in the model included seson, tretment, nd seson x tretment. Differences were considered significnt t P<0.05. Results nd Discussion: A significnt grzing tretment x seson interction occurred. Therefore results re presented y smpling dte. The generl differences of the pstures fter livestock ws removed were very pprent. In the co-grzed, totl vegettion ws utilized more uniformly thn in the cttle lone tretment. Gots rowsed utumn olive (Elegnus umellt Thun.) shruery ggressively (Fig. 1). Forge mss differed etween tretments for ll smpling dtes (Fig. 2). In the spring (initil smpling) there ws no difference in iomss yield mong the co-grzed nd cttle tretments (Fig 2). In mid-summer, generlly the overll iomss yield incresed minly due to the summer species (such s serice lespedez). After two cycles of grzing y cttle nd co-grzed, iomss yield decresed significntly compred with the ungrzed control. Furthermore, iomss yield ws significntly lower for co-grzed compred with cttle or the ungrzed 2

3 control. Although differences were much lower, the sme trend ws oserved t the end of the grzing seson (Fig. 2). Visul ssessment of otnicl composition of the swrd indicted tht erlier during the grzing seson, the dominnt frction of the swrd ppered to e grss nd weeds (including serice lespedez) with smller mounts of desirle legumes (Fig. 3.). However, y the end of the grzing seson, the grss component of the swrd ws significntly higher in co-grzed tretment compred to ungrzed control proly due to got preference for weeds llowing grsses to occupy more re nd tke dvntge of ville light nd nutrients. Weed components of the swrd ws reduced for cttle nd co-grzed tretments compred with the ungrzed control (Fig. 3). Luginuhl et l. (1999; 2000) found similr results under co-grzing cttle nd gots in North Crolin. Initil results from the current study indicte tht co-grzing y gots nd cttle could more effectively utilize the complex mixture of herceous nd woody vegettion commonly found in reclimed mined lnd pstures in the southestern United Sttes. This could increse niml production per unit re nd improve the profitility of this mrginl lnd resource. More work is needed to determine stocking densities nd rtios tht will mintin desirle lnce of herceous nd woody vegettion cple of supporting sustinle co-grzing systems. Literture Cited: Aye, A. O., V.G. Allen, nd J. P. Fontenot The doule DAFOR scle: A visul technique to descrie otnicl composition of pstures. p In Proc. Forge nd Grsslnd Conference. Fort Worth, TX. Allen, V.G. nd M. Collins Grzing mngement systems. p In R.F. Brnes, C.J. Nelson, M. Collins, nd K.J. Moore. (eds). Forges: An introduction to grsslnd griculture. 6 th ed. Iow Stte Press, Ames. Bll, D.M., C.S. Hovelnd, nd G.D. Lcefield Forges for gots, deer, sheep, llms, nd rtites. In: Southern Forges: Third Ed. Potsh nd Phosphte Institute, Norcross, GA. Brodie, J Vegettion nlysis. p In Need editors here. Grsslnd studies. George Allen & Unwin, Boston. Dove, D. D. Wolf, nd C. Zipper Conversion of serice lespedez-dominnt vegettion to qulity forges for livestock use. VA Coop. Ext. Pu Glimp, Hudson A Met got production nd mrketing. J. Anim. Sci. 73: Luginuhl, J-M., T.E. Hrvey, J.T. Green, Jr., M.H. Poore, nd J.P. Mueller Use of gots s iologicl gents for the renovtion of pstures in the Applchin region of the United Sttes. Agroforestry Systems 44: Luginuhl, J. M., J.T. Green, M. H. Poore nd A. P. Conrd Use of gots to mnge vegettion in cttle pstures in Applchin region of North Crolin. Sheep nd Got Res. J. 16: SAS SAS User s Guide: Sttistics. SAS Inst., Inc. Cry, NC. 3

4 Figure 1. Gots rowsing utumn olive shru Forge mss (ls DM/cre) c c Control Cttle Mixed 0 spring summer utumn Seson Figure 2. Effect of co-grzing vs. cttle lone grzing on herceous mss over sesons. Mens for rs within sesons followed y the sme letter re not significntly different (DMRT, P = 0.05). 4

5 Composition (%) weed grss legume Control Cttle Mixed Control Cttle Mixed Control Cttle Mixed Spring Summer Autumn Seson Figure 3. Effect of co-grzing vs. cttle lone grzing on otnicl composition over sesons. Mens for rs within sesons followed y the sme letter re not significntly different (DMRT, P = 0.05). 5