25. CROP ROTATIONS 2: ALSIKE CLOVER AND ANNUAL CROP PRODUCTION by Garry Ropchan

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1 25. CROP ROTATIONS 2: ALSIKE CLOVER AND ANNUAL CROP PRODUCTION y Grry Ropchn INTRODUCTION Although legume crops re not commonly grown in rottions y nnul crop producers, recent chnges in frming economics require tht we reexmine the role nd enefits of these crops. The gretest stigm tht cn e ttched to nnul crops is the pprent view tht these crops do not produce the income strem tht common nnul crops such s cnol nd spring whet cn. Producers need to consider tht while legume crops cn e used for livestock feed or grown for seed production (see Tle 25.1), there most significnt enefit my lie in the nitrogen they re fixing during their lifespn. Tle 25.1 Common Legume Seed Prices Legume Crop Current Price* Long Term* Red Clover $ /l $ /l Alsike Clover $ /l $ /l Alflf $ /l $ /l Sweet Clover $ /l $ /l *s supplied y Brett Young, Rycroft, Jn While some of this nitrogen is used y the seed or removed in hying/grzing opertions, the elow ground portion tied up in the root mss cn e ville for susequent nnul crops to use. This nitrogen cn replce some or ll of the nitrogen tht producer would normlly pply to his nnul crops. In nother tril, shown in Tle 25.2, whet ws plnted the yer fter legumes to determine the nitrogen replcement vlue of growing the legume crop. Tle 25.2 Nitrogen replcement vlue of legumes to following crops t Winnipeg, 2000 N source N Added to Soil l/c Vlue of N $/c* Chickling Vetch Red Clover Lentil Alflf (1 yer) * nitrogen source used for vlution t $0.48/l of N) Unfortuntely, we hve seen producers move to shorter rottions consisting of spring nnul crops solely due to csh flow considertions. Shorter rottions, often involving cnol followed y cerel crop then cnol gin, cn led to prolems with pest nd disese outreks. As we shorten the period etween similr crops we cn crete the opportunity for prolems to occur. Recent drmtic increses in crop input costs, especilly nitrogen (see Tle 25.2) nd decreses in nnul crop prices like cnol, re cusing producers to re-think their cropping progrms. Tle 25.2 Exmple of Fertilizer Prices Fertilizer 2000 Price/l* 2006 Price/l* *Prices from spring of the yer from Agricore- United in Spirit River/Rycroft As frming opertions ecome lrger nd more intense in scope, the pressure to get the crop into the ground in the shortest possile time ecomes greter. Often producers re forced to look fter frming ctivities while ignoring other spects of their lives, such s spending time with their fmilies. Crop rottions cn provide producers with the opportunity to spred out their work-lod, reduce their crop investment risk nd diversify the ecologicl environment of their lnd se. Inclusion of legume crop, like lsike clover, in crop rottions cn py significnt enefits through their ility to fix tmospheric nitrogen. This nitrogen is then mintined in the soil where it cn e used y susequent nnul crops thus reducing the nitrogen fertilizer tht must e purchsed y the producer. Incresing the use of legume crops will help to extend the supply of trditionl fertilizer sources mnufctured from nturl gs. Tle 25.3 elow shows estimtes of yerly nitrogen fixtion y lsike clover. A portion of this fixed nitrogen is removed s hy nd does not remin in the soil. But wht is left s root exudtes, decying roots nd ove ground plnt mss is significnt nd helps to mintin soil fertility. Tle 25.3 Estimted Annul Nitrogen Fixtion (kg/h) y Perennil Legumes from Agriculture Cnd Reserch Sttion, Beverlodge Legume Crop In Grey Soil, l/c* Alsike Clover 135 *Nitrogen fixtion estimtes include nitrogen in the totl plnt 1

2 Field studies hve shown tht etween 10 nd 20 per cent of the totl nitrogen dded to the soil though y green mnure crop is used y the first susequent nnul crop. An dditionl 64 per cent of the legume nitrogen cn e found in the top 1.2 meters (4 ft) of soil 14 months fter green mnure crop. This nitrogen ecomes ville s plnt residues continue to decompose. The timing of legume incorportion should mximize top-growth nd nitrogen fixtion while minimizing soil moisture depletion. The present recommendtion is incorportion t full loom. After full loom the plnt mteril ecomes tougher nd will tke longer to decompose nd relese plnt nutrients for susequent crops. Very young plnt mteril, on the other hnd, my decompose quickly fter incorportion, leving the relesed nitrogen vulnerle to leching nd voltiliztion. It is of importnce for producers evluting legume crops in rottion to consider how different legumes vry in terms of oth their ility to fix nitrogen nd how soon they cn do this in the growing seson. For exmple, with red nd lsike clover the differences cn e drmtic nd worth considering. AAFC Beverlodge trils (Rice nd Hoyt, ) compred lsike nd red clover oth for their ility to fix nitrogen (Tle 25.7) nd how rpidly this is ccomplished. In the cse of lsike clover, y the end of July it hs fixed 85% of its potentil yerly totl. Red Clover, on the other hd, hs only mnged to fix 73% of its potentil yerly totl y the end of July. It would pper tht when selecting from these two legume crops, producers should opt for lsike clover for its ility to fix more nitrogen nd to do so sooner in the growing seson thn red clover. Tle 25.7 Annul Nitrogen Fixtion By Alsike Clover Grown On A Gry Luvisol Soil. Yer Plnted Yer Mesured Alsike Clover l/c Averge 72 Source: Rice nd Hoyt, Winter crops such s fll rye or winter whet involve field opertions tht re potentilly less usy thn the spring, y moving the seeding nd hrvesting opertions from My nd Octoer to August. Winter crops egin growing much erlier in the spring nd cn usully e vigorously growing prior to most nnul weeds. It is not uncommon for producers who grow winter whet to report tht there is no need for grssy weed hericide due to the competitive nture of the winter whet choking out the wild ots. OBJECTIVES The ojective of this tril is to compre the economics of seeding nnul crops into Alsike clover stule grown for seed production over severl yers using three different producer fertilizer regimes. Initilly HRS whet will e grown, followed y cnol Brett Young Site METHODS The plot re ws seeded to lsike clover for seed production in Seed crops were hrvested in 2004 nd John Brrich custom comined the lsike clover in 2005 with John Deere 9750 comine nd it did superior jo with very fine strw chopping, considertion for producers who wish to direct seed nnul crops. On My 3 rd urnoff hericide ppliction ws mde consisting of the recommended rte of Eclipse (0.5 l/c Roundup Trnsor with l/c clopyrlid/lontrel). This product ws selected for the improved clover control tht would e chieved y hving clopyrlid in the tnkmix nd it is more ffordle thn uying the two hericides seprtely (this is hint people!). The clover t this time ws out 15 cm/6 inches in height. The 0-6 soil test reveled the following informtion: Nitrogen: 64 l/c, deficient. Phosphorus: 48 l/c, mrginl. Potssium: 857 l/c, optimum. Sulfur: 68 l/c, optimum. EC: 0.38, good. ph: 5.5, cidic. Orgnic Mtter: 10.0 %. The trget yield of 50 u/c of HRS whet clled for: 57l N, 21 l P 2 0 5, 0 l K 2 O nd 19 l S /c. CDC Imgine HRS Whet ws seeded t rte of 120 l/c on My 15 th t depth of 0.5 using Hyuster 8000 zero till hoe drill with 10 2

3 spcing nd 3 pired rows. There were three different fertilizer tretments used: A rndomized complete lock design ws utilized with three replictes. PLOT PLAN: north side south side The fertilizer ws deep nded t the time of seeding 1.5 elow the middle of ech pired seed row. Oservtions mde t the time of seeding found tht the urnoff hericide performed remrkle well, there were few res t the edges of the plot re where the spryer hd not een turned on fst enough nd it ws esy to see tht the clover ws ctively growing in these res. Oservtions mde during the growing seson found tht we could not tell visully etween the three tretments. The plots were swthed on August 22 nd nd comined on Septemer 17 th. The strips were weighed with weigh wgon nd smples were retined to determine % dockge, % moisture nd grde. The results re given in Tle 25.9 nd Figure Aove: The tretment on August 22 nd, Aove: The tretment on August 22 nd, Aove: The tretment on August 22 nd,

4 TABLE 25.9 Effect of Nitrogen Rte on HRS Whet Seeding Into Alsike Clover Stule, Brett Young Site, 2006 Tretment Yield u/c* % Moist.* % Dock.* Bu. Weight l/u* % Protein* Tretment Cost $/c Cont. Mrgin $/c c P CV 3.3% 2.2% 28.7% 0.5% 0.9% *mens followed y the sme letter re not significntly different t P=0.05, #3 HRS Whet 13.3% $2.82/u, #3 HRS Whet 13.8% $2.88/u, #3 HRS Whet 14.4% $2.94/u, spring 2006 $0.48/l of N c 0 YIELD BU/AC % PROTEIN BUSHEL WEIGHT l/u CONTRIBUTION MARGIN $/AC FIGURE 25.1 EFFECT OF N FERTILIZER RATE ON HRS WHEAT GROWN ON ALSIKE CLOVER STUBBLE, BRETT YOUNG SITE, RESULTS AND DISCUSSION At the Brett Young site in 2006 there were significnt differences in yield (P=0.01) nd in % Protein (P=0.001) of the three tretments. The nd yielded higher thn the tretment. The tretment hd higher % Protein thn the nd tretments. The tretment hd higher % Protein thn the tretment. There were no 4 significnt differences in % Moisture (P=0.73), % Dockge (P=0.89) nd Bushel Weight of the three tretments. Contriution Mrgin decresed s N rte incresed CONCLUSIONS

5 Legumes cn e n overlooked component of n nnul cropping progrm. With the current trend to incresing fertilizer prices, it my e time to rethink the vlue of these crops. While plnting legume crops like lsike clover cn generte income through seed production, they cn lso e providing n economic enefit in the yers fter they hve een removed from production through the N minerliztion tht occurs to the lsike clover plnt mtter (especilly the roots). In order to evlute the totl enefit of these legume crops, it will e necessry to look t their enefit over severl yers. It is hoped tht we will continue with this tril in 2007 when we will plnt Argentine cnol. Bsed on the 2006 results, there pper to e significnt enefits from plnting n nnul crop into lsike clove stule without dding ny supplementl fertilizer. While oth fertilizer tretments ( nd ) resulted in the whet hving significntly higher protein vlues nd higher yields, this ws not le to offset the higher costs ssocited with the N fertilizer used. REFERENCES HOYT, P.B. nd HENNING, A.M.F Effect of lflf nd grsses on yield of susequent whet crops nd some chemicl properties of greywooded soil. Cn. J. Soil Sci. 51: RICE, W. nd HOYT, P.B. Forge seed notes. Alert Forge Seed Council. MANITOBA CROP INSURANCE CORPORATION, 5