NUTRIENT MANAGEMENT EM 8854-E Revised Ferury 2011 Annul Ryegrss Grown for Seed (Western Oregon) J.M. Hrt, M.E. Mellye, W.C. Young III, nd T.B. Silerstein Summry Fll, efore plnting Note: For fields estlished y volunteer seedlings, no fll nutrient pplictions re recommended. Lime Apply lime ccording to Tle 6 when the soil ph is elow 5.5. See pges 4 6. Nitrogen (N) Appliction of 20 l N/ is common nd optionl. See pge 3. Phosphorus (P) When soil test P is elow 25 ppm, pply P ccording to Tle 2. See pges 3 4. Potssium (K) When soil test K is elow 150 ppm, pply K ccording to Tle 4. See pge 4. Clcium (C) When soil test C is elow 5 meq/100 g of soil or 1,000 ppm, pply lime. See pge 6. Mgnesium (Mg) When soil test Mg is elow 0.5 meq/100 g of soil or 60 ppm, use 1 t dolomite/ for 1 t lime/ of the lime requirement. See pge 6. Spring Note: These spring nutrient pplictions pply to ll fields, including those estlished y volunteer seedlings. Nitrogen (N) Apply 100 to 140 l N/ etween mid-mrch nd mid-april. See pges 6 8. Sulfur (S) Apply 10 to 15 l S/ in erly spring with the first ppliction of N. S cn e pplied every other yer t 20 to 25 l/. See pge 8. Potssium (K) K my e pplied in the spring for mintennce purposes. If soil test indictes the need for K, pply in the fll. Chloride (Cl) No ppliction is recommended. See pge 9. Photo: Mrk Mellye Annul ryegrss is grown for seed primrily on Dyton, Bshw, nd similr poorly drined soils in western Oregon. Dyton, clled white soil y growers, is found on rod, flt res of the southern Willmette Vlley floor. Bshw, lck, sticky cly sometimes clled gumo soil y growers, is formed on the low-lying nd gently concve res ssocited with nrrow strem vlleys nd t the edges of some hill slopes. These soils re not well suited to perennil grss production ecuse of poor dringe, which cuses wter to stnd on the soil surfce. Recommendtions in this guide ssume production in these settings nd pply to commonly grown vrieties of nnul ryegrss. Mngement prctices, from seeded preprtion to hrvest, must e performed in n pproprite nd timely mnner for optimum nnul ryegrss seed yield. Fertilizer is not sustitute for filure to control insects, diseses, or weeds. Excessive stnd density, low soil ph, nd/or poor dringe cn e significnt limiting fctors in otining high seed yields. Incresing fertilizer rtes or dding nutrients lredy in dequte supply will not correct these limiting fctors. Nutrient mngement cn e ddressed y nswering the following questions: How much fertilizer should e pplied? When should the mteril e pplied? How should the mteril e pplied? Wht mteril should e used? This guide primrily nswers the first two questions. 1 John M. Hrt, professor of crop nd soil science, emeritus; Mrk E. Mellye, re Extension gronomist; Willim C. Young III, Extension seed production specilist; nd Thoms B. Silerstein, re Extension gronomist; ll of Oregon Stte University.
The verge seed yield for nnul ryegrss is pproximtely 2,000 l/. Higher yields do not require greter mounts of nutrients thn recommended y this guide. These recommendtions, especilly those for nitrogen, re dequte for seed production of more thn 3,000 l/ on sites where soil ph nd dringe do not limit yield. For informtion out djustments needed sed on the method of stnd estlishment, see the sider Stnd estlishment method nd nutrient mngement. Recommendtions in this guide re the result of 50 yers of lrge- nd smll-plot reserch throughout the Willmette Vlley (see pge 10). Severl reserch projects evluted the impct of grzing on nnul ryegrss seed yield. No reduction in seed yield ws mesured from grzing durtions etween lte Ferury nd erly to mid- April. However, lte-spring grzing will remove the picl meristems (growing points) of primry tillers. Thus, to mintin seed yield under grzing mngement, sufficient nutrients nd moisture for regrowth re necessry during the post-grzing period. Soil smpling nd nlysis Smple nd nlyze soil to estimte the need for lime, phosphorus, potssium, clcium, nd mgnesium. Smpling soil every second or third yer is sufficient. A single smple should represent only 40 cres, single soil type, or the sme mngement prctices in field. Crop growth nd nitrogen uptke Rte nd timing recommendtions for nitrogen (N) re sed on plnt demnd. Annul ryegrss growth nd N uptke ptterns help determine ppliction timing (Figure 1). Cumultive iomss (l/) Cumultive N uptke (l/) N uptke rte (l//dy) 10,000 8,000 6,000 4,000 2,000 0 1/1 2/1 3/1 4/1 5/1 6/1 120 100 80 60 40 20 0 1/1 2/1 3/1 4/1 5/1 6/1 2 1 0 1/1 2/1 3/1 4/1 5/1 6/1 Dte Figure 1. Biomss ccumultion nd N uptke for highyielding nnul ryegrss grown in the southern Willmette Vlley. Dt re from 1991. Stnd estlishment method nd nutrient mngement Before 1985, much of the nnul ryegrss strw ws urned, nd susequent plntings were no-till seeded. Current legisltive sttutes prohiit open field urning of residue in nnul ryegrss seed production. Now, nnul ryegrss is estlished (1) y plnting in conventionlly prepred seeded, (2) y direct seed or no-till plnting, or (3) with volunteer seedlings from the previous yer s crop. Recommendtions in this guide pply to ll common methods of estlishing stnd. Only minor djustments re needed for ech method. In generl, if the seed is drilled, we recommend fll ppliction of nutrients (preplnt or nded t plnting), except nitrogen. Recommended rtes re discussed on pges 3 6. Using volunteer seedlings for stnd estlishment reduces tillge nd plnting cost. However, nutrients ren t incorported t plnting with this method. For these stnds, only spring N nd S will e pplied. For this reson, volunteer stnd estlishment should e used only when soil ph nd nutrient levels re dequte. Volunteer stnd estlishment is recommended when soil ph is ove 5.3, soil test phosphorus is ove 25 ppm, soil test potssium is ove 150 ppm, soil test clcium is ove 5 meq/100 g soil (1,000 ppm), nd soil test mgnesium is ove 0.5 meq/100 g soil (60 ppm). Do not use volunteer stnd estlishment where soil ph is elow 4.8. To tke dvntge of the cost sving from volunteer stnd without reducing yield, competition must e reduced. Bnding hericides to estlish rows nd hevy grzing with sheep re two common wys to reduce competition. 2
Growth is slow during fll nd winter. Depending on the yer nd whether fields re grzed, etween 500 nd 1,000 l dry mtter/ is ccumulted y mid-mrch. Growth is rpid nd liner from erly April to erly June. Approximtely 100 to 125 l N/ is tken into the oveground portion of the crop when 90 to 135 l N/ is pplied in spring. The mximum N uptke rte is pproximtely 1.5 l//dy during lte Mrch nd erly April. Intensive grzing will dely iomss nd N ccumultion. At physiologicl mturity, the totl oveground iomss of pproximtely 9,000 l/ consists of 2,700 l seed/ nd 3 t strw/. Strw N concentrtion is out 1 percent, nd seed N concentrtion is out 2 percent. Slightly less thn hlf of the N is removed in the seed. Fll nutrient mngement In generl, if the seed is drilled, we recommend fll ppliction of nutrients (preplnt or nded t plnting), except nitrogen. Recommended rtes re discussed in ech of the sections elow. For volunteer-estlished stnds, no fll fertilizer is recommended. Nitrogen (N) Trditionlly, fll ppliction of 20 l N/cre ws recommended, sed on reserch with open field urning followed y no-till plnting. A seed yield increse from fll ppliction of N is not documented with current estlishment methods. For exmple, little or no increse in seed yield ws mesured from lte-fll/erly-winter N ppliction when the nnul ryegrss crop ws estlished from volunteer stnd nd rows were estlished with winter hericide ppliction. A Decemer ppliction of 20 l N/ s liquid spryed over rows provided n insufficient seed yield increse to recoup the cost of ppliction (Figure 2). A seed yield increse of t lest 80 l/ is necessry to recover the cost of 40 l N/ if N costs $0.50/l (ure t $460/t) nd the price for seed is $0.25/l. Clen seed yield (l/) 2,800 2,400 2,000 1,600 Check Roundup Roundup + Diurex Roundup + Diurex + fertilizer Figure 2. Clen seed yield response to hericide nd fertilizer tretments for estlishment of rows in volunteer stnd of nnul ryegrss. The fertilizer ws liquid 20-3-3-3 pplied over the row t the rte of 10 gl/ (20 l N/) in Decemer. 3 Field reserch hs shown tht fll N ppliction is less importnt to seed production thn is spring N ppliction (Tle 1). Seed ws hrvested from nnul ryegrss receiving either 0 or 40 l N/ s preplnt rodcst ppliction. All tretments received 15 to 25 l N/ in nd t plnting. The crop residue ws either urned or chopped nd plowed into the seeded. Tle 1. Influence of residue mngement, fll nitrogen ppliction, nd spring nitrogen rte on nnul ryegrss seed yield, clened. Preplnt rodcst Residue fll N Spring N Seed yield mngement (l/) (l/cre) (l/) Burn 0 80 2,226 0 120 2,481 40 80 2,241 Chop/plow 0 80 2,182 0 120 2,483 40 80 2,120 LSD 0.05 ~200 c Dt were collected from plots ner Shedd, Oregon, from 1983 through 1985 nd re tretment verges. All tretments received 15 to 25 l N/ in nd t plnting. The rte vried nnully. c A seed yield difference of less thn 200 l/ ws not sttisticlly significnt in this tril. Although fll pplictions of N hve not produced documented increses in seed yield, use of fertilizer t plnting cn promote erly growth, id in estlishment efore winter, nd provide dditionl forge for grzing. If fll N ppliction is mde, nd mximum of 20 l N/cre. If desired, N cn e pplied to volunteer stnds during row spry opertion. Ammonium phosphte, the most common phosphorus fertilizer, contins N. Thus, if 30 l P 2 O 5 / is nded t plnting, 15 to 25 l N/ typiclly is supplied. Phosphorus (P) Annul ryegrss hs pproximtely the sme need for P s do other grsses grown for seed in the Willmette Vlley. Between 10 nd 15 l P/ is contined in mture nnul ryegrss crop tht yields 2,000 l seed/. A smll mount, etween 1 nd 2 l P/, is contined in the seed. When P limits seed yield, the yield increse from P ppliction is pproximtely 300 l/. In comprison, seed yield increse of 500 to 1,000 l/ is common from pplictions of N fertilizer. Determine P need from soil test nd the ppliction rte from Tle 2 (pge 4). When needed, nd P ner the seed t plnting.
Tle 2. Phosphorus ppliction rtes sed on soil test. Soil test P Apply this mount of P 2 O 5 (ppm) (l/) 0 15 40 60 16 25 30 40 Over 25 0 Bry P1 soil test method. Potssium (K) Potssium concentrtion in the seed of cool-seson grsses is constnt, pproximtely 0.6 percent or 12 l/t of seed. Thus, little K (only out 10 to 15 l/) is removed from n nnul ryegrss field in seed. Considerly more 30 l K/ or more leves the field in led strw. Tle 3 gives mounts of K in grss seed strw. Tle 3. Potssium concentrtion nd content in strw of grsses grown for seed. K in strw of grss seed crop (%) (l/t) (l/) Annul ryegrss 0.75 15 30 Perennil ryegrss 1 2 20 40 50 100 Tll fescue 1 2 20 40 60 120 Averge strw produced: nnul ryegrss = 2 t/; perennil ryegrss = 2.5 t/; tll fescue = 3 t/. Becuse most of the K in grss seed crop is contined in the strw, K mngement depends on strw mngement. When nnul ryegrss strw is chopped nd plowed into the soil or chopped nd left on the surfce, little K leves the field. Potssium in strw is very solule nd leches from the strw into the soil with fll rins. It is redily ville nd cn e used y seedlings. With field urning restricted, mny growers in the southern Willmette Vlley re now ling nnul ryegrss strw. Where strw is led nd removed, much more K leves the field thn where strw is retined, nd soil test K levels decline more rpidly. Growers should py creful ttention to soil test K depletion nd the economics of ling strw. Determine K need from soil test nd the ppliction rte from Tle 4. Reduction of nnul ryegrss yield from K deficiency is not expected until soil test K is elow 75 ppm. The recommended soil test level ove which no K is recommended is 150 ppm. Use the higher ppliction rtes in Tle 4 on Dyton soils to compenste for declining soil K supply with depth (pproximtely 100 ppm in the first foot nd 75 ppm in the second foot). In contrst, Bshw soil usully hs more thn 200 ppm in the top 2 feet of the profile, so the lower rtes re dequte. When K is plced with the seed, rtes should not exceed 30 to 40 l K 2 O/. Tle 4. Potssium ppliction rtes sed on soil test nd residue mngement. Soil test K Apply this mount of K 2 O (ppm) (l/) Ble Chop 0 100 60 90 30 60 101 150 30 60 0 30 Over 150 0 0 Ammonium cette method. Use the higher rtes on Dyton soils. Sulfur (S) Although S cn e pplied in the fll, spring ppliction is preferle. See pge 8 for rtes nd informtion. Lime, clcium, mgnesium, nd ph Annul ryegrss is widely dpted cool-seson grss, tolernt of oth poor dringe nd low soil ph. Even so, lime ppliction is suggested when the soil ph is less thn 5.5. Although nnul ryegrss cn e produced t lower soil ph, the risk of stnd filure nd depressed yield increses rpidly s soil ph decreses. In 3-yer tril conducted on Dyton soil ner Hlsey, Oregon, lime ws pplied to field of Gulf nnul ryegrss on very cidic soil. Lime ppliction produced smll ut significnt increse in seed yield (200 to 320 l/), s shown in Tle 5. Aluminum (Al) toxicity is considered primry plnt growth-limiting fctor in strongly cidic soils. As soil ph decreses, extrctle Al increses exponentilly nd grss seed yield decreses. The soil ph t which Al ecomes toxic to plnts depends on the soil, plnt species, Tle 5. Chnges in 3-yer verge seed yield, soil ph, nd extrctle C from lime pplictions. C Seed yield ph (meq/100 g soil) Lime rte (l/) (t/) Yer 1 Yer 3 Yer 1 Yer 3 3-yer verge 0 4.2 4.4 2.1 2.2 2,515 0.075 4.2 4.3 1.8 2.1 2,740 2.5 5.4 4.7 6.1 4.4 2,723 5 6.0 5.1 11.3 6.5 2,837 Grnulr lime nded t rte of 150 l/. By-product, lime score of 72, pplied 20 August, 2005 to provide n equivlent mount of 100-score lime. 4
nd vriety grown. In Willmette Vlley soils, ph of 4.7 hs een considered level t which Al concentrtion egins to increse exponentilly nd ffect the growth of grss roots in forge nd seed production systems. (See the sider Should soils e tested for luminum? ) Seed yields were ove the industry verge of 2,000 l/ even when extrctle Al ws three times the mount thought to ffect root growth. One possile reson for this result is tht soil orgnic mtter cn reduce the effect of Al toxicity on root growth. This explntion is possile since totl soil cron t the site ws 2.5 percent. Another possile explntion is tht the Gulf nnul ryegrss cultivr grown in Oregon my hve developed tolernce to lower soil ph. The seed stock of Gulf nnul ryegrss used in this tril cme from the sme frm nd from fields with similr low soil ph. Regulr soil smpling nd testing to monitor soil ph chnges is recommended. Sesonl fluctution of soil ph mkes yer-to-yer comprison difficult unless soil smples re collected t the sme time ech yer, for exmple, in the summer efore plnting. Soil ph increses s soil is wetted with fll nd winter rin. Soil ph is highest in the wettest time of the yer, Ferury or Mrch. Mesured soil ph lso depends on smpling procedure nd cn vry throughout field. Our recommendtion for lime ppliction when soil ph is elow 5.5 provides mrgin of sfety. The mount of lime required to increse soil ph is sed on the SMP lime requirement test, lso known s uffer test (Tle 6). It is nmed fter the three scientists who introduced the test, Shoemker, McClen, nd Prtt. The SMP uffer test is mesured in the sme units s soil ph, ut it is different test. Soil uffer or SMP ph usully is out 0.8 ph unit higher thn soil ph. Tle 6. SMP lime requirement when soil ph is elow 5.5. Amount of 100-score lime needed to rise ph of surfce 6 inches of soil to the following ph, (t/) SMP uffer 5.6 6.0 4.8 5.0 6 5 8 7 5.1 5.3 5 4 7 6 5.4 5.6 4 3 6 4 5.7 5.9 3 2 4 3 6.0 6.2 2 1 3 2 6.3 6.5 0 2 1 6.6 0 1 Rtes re sed on 100-score lime. The comintion of clcium cronte equivlent, moisture, nd fineness determines lime score. Lime ppliction rtes re djusted for score. Lime score is leglly required for ll mterils mrketed s liming mterils in Oregon. For more informtion out lime score nd liming mterils, see FG 52, Fertilizer nd Lime Mterils Fertilizer Guide. Use the higher lime ppliction rte for the lower uffer test vlue. Should soils e tested for luminum? Lime ws pplied to n cidic nnul ryegrss field ner Hlsey, Oregon. Annul ryegrss seed yield nd soil chemicl properties were mesured for 3 yers (Tle 5, pge 4). Mximum nnul ryegrss seed yield ws chieved when extrctle luminum (Al) ws elow 100 ppm. At soil ph of pproximtely 4.7, extrctle Al incresed shrply, reching pproximtely 100 ppm (Figure 3). Thus, soil ph of 4.7 is considered the threshold vlue t which Al egins to limit root growth in this re. Although resonle reltionship exists etween extrctle Al nd nnul ryegrss seed yield (Figure 4), use of extrctle Al to predict lime need is not recommended. The test is not universlly ville, nd criticl Al levels vry with soil nd crop. The strong reltionship etween extrctle Al nd soil ph in Figure 3 shows tht soil ph is n dequte indictor of the mount of Al in the soil nd the need for lime. Extrctle Al (ppm) 500 400 300 200 100 0 4.0 4.5 5.0 5.5 6.0 6.5 7.0 Soil ph Figure 3. ph chnge mesured in extrctle luminum with 2:1 wter:soil. Seed yield (l/) 3,500 3,100 2,700 2,300 1,900 1,500 0 100 200 300 400 KCl extrctle Al (ppm) Figure 4. Chnge in nnul ryegrss seed yield with KCl-extrctle Al. 5
Photo: Mrk Mellye Figure 5. Incorporte lime into the soil efore plnting. Clen seed yield (l/) 3,000 2,500 2,000 1,500 500 1983 1985 1953 1954 2000 2001 0 40 80 120 160 200 240 280 N rte (l/) Figure 6. Annul ryegrss seed yield chnge with rtes of spring-pplied N. Dtes of field experiments re noted. Some soil test results might hve high SMP uffer vlue (greter thn 6.2) nd soil ph elow 5.3. This condition typiclly occurs when soil smples re tken in August or Septemer. Spring fertilizer ppliction nd very dry summer conditions cn comine to temporrily depress soil ph. Work lime into the soil efore plnting (Figure 5). Lime pplictions of less thn 4 t/ re effective for severl yers if thoroughly mixed with the soil. When the SMP test result is elow 5.2, lime pplictions greter thn 4 t/ re recommended (Tle 6, pge 5). Do not exceed 5 t/ in single ppliction, ecuse mixing lrger mounts with the soil is difficult. If the recommended mount of lime exceeds 5 t/, split the ppliction over 2 or 3 yers or plow down hlf the lime nd hrrow in the reminder. When pplying lime over 2- or 3-yer period, test soil ph nd SMP uffer efore the second ppliction. A low rte of grnulr lime (100 to 150 l/) nded during plnting is n economicl option for mintining seed yield on fields with low soil ph (see Tle 5, pge 4). Bnding lime is recommended when the soil ph is etween 5.0 nd 5.5. However, the rte of lime used for nd ppliction is insufficient to increse soil ph or soil C or to decrese extrctle Al levels throughout the root zone. Therefore, it is recommended s shortterm mngement option, rther thn s replcement for rodcst lime ppliction. Bnding is recommended for only 2 or 3 yers. Conventionlly incorported lime pplictions, while more expensive, provide greter ssurnce of incresing soil ph, reducing extrctle Al, nd incresing seed yields on strongly cidic Willmette Vlley soils, not only for nnul ryegrss, ut for other crops tht my e grown in rottion. Clcium (C) nd mgnesium (Mg) re essentil plnt nutrients. Soil test C elow 3 meq/100 g soil (600 ppm) is often ssocited with low soil ph nd high extrctle Al, conditions tht limit nnul ryegrss root growth. When soil ph is ove 5.5, soil test C usully is 10 to 15 meq/100 g soil (2,000 to 3,000 ppm) for Bshw soil nd 8 to 12 meq/100 g soil (1,600 to 2,400 ppm) for Dyton soil. At this soil ph, soil test Mg usully is 2 to 5 meq/100 g soil (240 to 600 ppm) for Bshw soil nd 1 to 3 meq/100 g soil (120 to 360 ppm) for Dyton soil. Clcium nd mgnesium usully re present in dequte quntities when the soil ph is ove 5.0. For situtions where C is elow 5 meq/100 g soil nd soil ph is ove 5.0, pply 1 t lime/. For soils with ph elow 5.5 nd soil test Mg of less thn 0.5 meq/100 g soil (60 ppm), use 1 t dolomite/ to supply 1 t/ of the lime requirement. Dolomite nd limestone hve pproximtely the sme cpility to neutrlize soil cidity nd increse soil ph, so dolomite cn e sustituted for lime. An lterntive to dolomite is to rodcst 30 l Mg/ nnully. Compre mteril costs efore choosing mgnesium source. Spring nutrient mngement Nitrogen Nitrogen is supplied to nnul ryegrss from vriety of sources, including crop residue, soil, nd fertilizer. Soil cn contriute 60 to 100 l N/, depending on soil dringe, soil orgnic mtter content, nd spring soil temperture. Apply spring N to nnul ryegrss t rte of 100 to 140 l N/. Nitrogen rtes higher thn 150 l/ hve not een shown to increse seed yield enough to recover the cost of dditionl fertilizer. Excessive N rtes lso increse the need for lime. See the sider Effects of N fertilizer on soil cidity (pge 7) for more informtion. Figure 6 shows the reltionship etween nnul ryegrss seed yield nd spring N ppliction from three reserch efforts spnning lmost 50 yers. Although greter rnge of spring N ppliction rtes ws explored in the 2000 2001 trils, the conclusions from ll of the trils re similr. In ech study, pproximtely 120 l N/ ws sufficient for optiml nnul ryegrss seed yields. Optiml rtes vry due to differences in dringe, orgnic mtter, nd mngement. Soils with more thn 5 percent orgnic mtter produce less seed yield increse from N ppliction thn do other soils. Thus, n N 6
ppliction of 100 l/ might e dequte for Bshw or Awrig soil, while 140 l/ might e needed on soil with lower orgnic mtter content. Strw mngement hs little effect on N needs. Residue removl, urning, nd tillge hve little short-term effect on N supply to the crop. Tle 1 (pge 3) presents seed yield dt when residue is urned or chopped nd plowed into the seeded. When dequte spring N ws pplied (120 l/), yield ws identicl in fields where strw ws urned nd in those where strw ws incorported. Timing Timing of spring N pplictions requires considertion of oth plnt need nd field condition. In nongrzed fields, the mximum dily rte of N uptke, 1.5 l/, occurs in lte Mrch or erly April (Figure 1, pge 2). On these fields, pply N in mid-mrch to mid-april unless wet conditions restrict ccess. In fields tht re grzed, pply spring N s soon s sheep re removed from the field. Nitrogen cn e pplied in single or split ppliction. Growers cite evenness of ppliction s reson for split pplictions of spring N. However, in Willmette Vlley reserch, no increse in seed yield ws otined from split ppliction (Tle 7). Annul ryegrss fields often remin wet lte into the spring (Figure 7), so single ppliction fter fields hve dried is n option. Tle 7. Annul ryegrss clen seed yield from single or split spring N ppliction. Seed yield Nitrogen fertilizer (l/) ppliction method Site 1 Site 2 Split 2,550 2,385 Single 2,620 2,500 Site 1: Nitrogen ppliction split s 35 l/ in Mrch nd 93 l/ in April. Site 2: Nitrogen ppliction split s 68 l/ in Mrch nd 63 l/ in April. The mid-april single N ppliction rte ws 135 l/. Figure 7. If wet conditions limit field ccess, single N ppliction fter fields hve dried is n option. Effects of N fertilizer on soil cidity Use of most common N fertilizers increses soil cidity nd lime need. Tle 8 shows the effect of incresing N rte on soil ph in four southern Willmette Vlley soils. Ure nd other mmonicl N sources cidify soil pproximtely 0.1 ph unit for ech 100 l N/. For exmple, if ure is pplied t the rte of 140 l N/, soil ph will decrese y pproximtely 0.14 ph unit. If 140 l N/ is used for 3 yers, soil ph will decline pproximtely 0.4 ph unit. Thus, the use of N fertilizer eyond crop need hs doule cost. The first cost the N fertilizer itself is not offset y incresed seed yield or economic return. Second, the dditionl N cidifies soil, which then requires dditionl lime to rise the soil ph. Annul ppliction of 50 l N/ ove crop need will require n dditionl 0.3 to 0.6 t lime/ in 3 yers. Ure, the most common N source for nnul ryegrss seed production, is less cidifying thn mmonium sulfte ecuse the N in ure undergoes different process to ecome plnt-ville. As ure initilly rects with enzymes in the soil, soil ph rises slightly; this chnge prtilly offsets cidifiction produced y susequent rections. Tle 8. Soil ph from 0- to 2-inch depth, SMP vlues, nd lime rtes to rise the soil ph in grss seed fields fter 3 yers of nitrogen pplictions t three ppliction rtes. Dyton silt lom Concord silt lom Bshw silty cly lom Amity silt lom N rte Soil SMP Lime Soil SMP Lime Soil SMP Lime Soil SMP Lime (l/) ph ph (t/) ph ph (t/) ph ph (t/) ph ph (t/) 0 5.9 6.6 0 6.2 6.7 0 5.4 5.3 4.3 c 6.0 7.1 6.9 0 135 5.5 6.5 1 5.8 6.4 1.1 4.9 5.2 4.7 6.4 6.6 6.7 0 270 5.2 6.2 2 5.6 6.3 1.5 4.8 5.1 5.0 6.9 6.0 6.5 1 Smpled Novemer 2000. Lime to ph 6.0. c Lime to ph 5.6 7
Spring fertilizer N economics Annul ryegrss receiving spring ppliction of 100 to 140 l N/ produces pproximtely 1,000 l/ more seed thn does unfertilized nnul ryegrss (Figure 6, pge 6). If seed sells for $0.25/l, the incresed yield is worth $250. If N fertilizer costs $0.50/l, 120 l N costs $60. Add $5 for ppliction, nd the totl fertilizer cost is $65. An input cost of $65 produces return of $250. Growers sometimes wonder whether they should djust spring N rtes if the price of N fertilizer rises nd/or the price for seed flls. The nswer is simple: don t chnge the spring N rte s long s you re pplying 100 to 140 l N/. Consider the dt in Tle 9. The tle shows the mximum economic N rte when seed prices or fertilizer prices increse threefold. For exmple, the mximum economic N rte is 117 l N/ when the seed price is $0.15/l nd the N fertilizer price is $0.20/l. If the seed price doules to $0.30/l, the mximum economic N rte increses y only 5 l/ to 122 l/. Since the price of seed is unlikely to doule, the mximum economic N rte will chnge only slightly. Tle 9. Mximum economic spring nitrogen rte with vrying cost of nitrogen nd price received for nnul ryegrss seed. Price received for seed ($/l) Cost of N $0.15 $0.20 $0.25 $0.30 fertilizer Mximum economic N rte ($/l) (l/) 0.20 117 120 121 122 0.40 108 113 116 117 0.60 99 106 110 113 Conversely, when the fertilizer price triples ut the seed price remins unchnged, the mximum economic N rte decreses. Agin, the decrese is not lrge. For exmple, if seed sells for $0.20/l nd fertilizer N costs $0.20/l, the mximum economic N rte is 120 l/. If the cost of fertilizer N increses to $0.60/l, the mximum economic N rte is 106 l/, decrese of only 14 l/. In Tle 9, the center represents seed price of $0.20/l nd fertilizer cost of $0.40/l. Price chnges in ny direction will chnge the mximum economic N rte y less thn 10 l/. Most fertilizer spreders cnnot e djusted with this level of precision, nor cn fertilizer e spred this evenly. Growers often increse the N rte in n ttempt to increse yield nd profit. Figure 6 (pge 6) shows the increse in nnul ryegrss seed yield from N ppliction. Compre the shpe of the line for 2000 nd 1954. In oth cses, the point of mximum yield occurs t 120 to 160 l N/. Incresing the N rte produces greener plnt, ut Tle 10. The economics of N fertilizer ppliction on nnul ryegrss. Incrementl Fertilizer Clen seed Net return net return N rte yield ove N cost per $ invested (l/) (l/) ($/) ($/) 0 1,614 0 45 2,136 100 $6.65 90 2,428 149 $3.29 135 2,618 176 $1.78 180 2,645 167 $(-0.60) 225 2,645 152 $(-1.00) Dt from OSU spring N fertilizer trils (2000 2001). Price of N = $0.33/l; price for seed = $0.22/l. does not increse seed yield. Tle 10 further illustrtes this point. Incresing the fertilizer rte from 135 l N/ to 180 l N/ decresed the net return. Potssium If soil test indictes need for K, pply K in the fll. For mintennce purposes, K cn e pplied in the spring. Appliction of KCl is not needed in order to supply chloride. See the sider Spring potssium nd chloride ppliction (pge 9) for more informtion. Sulfur (S) Annul ryegrss hs pproximtely the sme need for S s do other grsses grown for seed in the Willmette Vlley. Between 15 nd 25 l S/ is contined in mture nnul ryegrss crop with 2,000 l/ seed yield. Soil testing for S is not recommended. An nnul ppliction of 10 to 15 l S/ is dequte for nnul ryegrss production. Sulfur cn e pplied in the spring or fll, ut spring ppliction (with the first N ppliction) is recommended. Sulfur ppliction is not needed every yer. Appliction of 20 to 25 l S/ cn e mde every other yer. Plnts use S from the soil in the form of sulfte, which is common component of multinutrient fertilizers such s triple sixteen (16-16-16), 16-20-0-14, nd ure-sul. The use of S-contining mterils often rises concern out possile soil cidifiction nd corresponding need for incresed lime. Not ll forms of S cidify soil. The ppliction of S in the sulfte form does not increse soil cidity nd the need for lime. Although mmonium sulfte cidifies soil, this effect is cused y the oxidtion of mmonium to nitrte, not y the presence of sulfte. Elementl S produces sulfuric cid nd increses the long-term need for lime. Elementl S usully is not recommended for use s fertilizer mteril in the Willmette Vlley. 8
Spring potssium nd chloride ppliction Potssium (K) ppliction on grss grown for seed hs trditionlly een mde in the fll. In the pst decde, some growers egn pplying K in the spring nd reported yield increses. Growers logiclly sked, When should K e pplied to grss for seed production? nd Does the chloride (Cl) from spring ppliction of potssium chloride increse seed yield? To nswer these questions, K nd Cl tril ws estlished during the spring of 2003 nd 2004 in commercil field of continuous Gulf nnul ryegrss ner Junction City. The soil series ws Bshw, typicl soil for nnul ryegrss production. Flg lef smples were collected s heding egn to evlute the influence of K nd Cl ppliction on tissue concentrtion. Both K nd Cl tissue concentrtion incresed when these nutrients were dded (Tles 11 nd 12). The 1,000-seed weight ws not chnged y Cl or K ppliction. Seed yield ws not incresed y K ppliction nd ws not expected to do so, s soil test K ws dequte (138 ppm K in the surfce 6 inches). Tle 4 (pge 4) Tle 11. Flg lef tissue chloride, tissue potssium, 1,000-seed weight, nd seed yield fter spring ppliction of potssium fertilizers, 2003. Tretment K 2 O Cl Tissue Cl Tissue K Seed wt Seed yield (l/) (ppm) (%) (g/1,000) (l/) 0 0 3,535 0.76 2.55 1,499 88 0 3,675 1.24 2.58 1,461 44 35 5,934 1.37c 2.65 1,535 88 70 7,206 1.56cd 2.68 1,525 176 140 11,567c 1.77e 2.63 1,515 NS NS Vlues followed y the sme letter re sttisticlly different. Tle 12. Flg lef tissue chloride, tissue potssium, 1,000-seed weight, nd seed yield fter spring ppliction of potssium fertilizers, 2004. Tretment K 2 O Cl Tissue Cl Tissue K Seed wt Seed yield (l/) (ppm) (%) (g/1,000) (l/) 0 0 3,108 1.28 2.90 2,630 88 0 3,154 1.50 2.85 2,758 44 35 4,503 1.42 2.91 2,696 88 70 6,880c 1.54 2.97 2,777 176 140 11,340d 1.77c 2.93 2,638 NS NS Vlues followed y the sme letter re sttisticlly different. recommends 0 to 30 l K 2 O/ t this K soil test level. The lowest K ppliction, 44 l K 2 O/, incresed flg lef K concentrtion to vlue no different thn tht mesured when 88 l K 2 O/ ws pplied. These dt nd seed yield dt in Tles 11 nd 12 sustntite recommendtions in Tle 4. When compred to tretments receiving no Cl ppliction, tretments receiving Cl produced n incresed seed yield in 2003 ut not in 2004. No explntion for the seed yield increse in 2003 ws found, nor did we identify wy to predict potentil seed yield increse from Cl ppliction. Soil test Cl did not predict whether site would produce incresed seed yield from n ppliction of Cl. The Cl soil test from 1-foot smple collection depth ws 88 l/, lmost triple the vlue used in North nd South Dkot to predict Cl need for whet production. Their recommendtion is to pply Cl if soil test Cl in the top 2 feet of soil is less thn 30 l/. Flg lef Cl concentrtion ws not helpful for identifying n insufficient mount in the plnt. In 2004, the flg lef Cl concentrtion ws 3,108 ppm with no chloride ppliction, nd seed yield did not increse with Cl ppliction. In 2003, flg lef Cl concentrtion ws higher (3,535 ppm), ut seed yield did increse with Cl ppliction. This reserch is prt of project conducted for 2 yers in nine loctions with three cool-seson grss species grown for seed. Limited nd unpredictle seed yield nd seed weight increse were mesured from Cl ppliction. Annul ryegrss ws the only species producing yield increse from the ppliction of Cl, nd the flg lef tissue Cl concentrtion from plots with no Cl pplied ws the highest of the three species. Our conclusion is tht spring ppliction of KCl to supply Cl to nnul ryegrss or other grss seed crops is not recommended, s no predictive mesurement is ville nd the seed yield increse from Cl ppliction is not economicl when KCl is routinely pplied. 9
Micronutrients No documented increse in growth or seed yield of nnul ryegrss from the ppliction of micronutrients hs een mesured in western Oregon. Soil test oron (B) levels normlly re very low in the Willmette Vlley, nd tissue nd soil test B levels will increse with soil B pplictions. However, seed yield increse from n ppliction of B rrely is mesured in grss seed crops. No seed yield increse from the ppliction of 1.25 l B/ ws mesured in field trils during 2000 (Tle 13). Boron pplied t 1 l/ every 3 or 4 yers my e used on tril sis where soil test B is less thn 0.3 ppm. Soil test levels for zinc (Zn) usully re dequte (0.6 ppm). In ddition to eing plnt nutrients, folir Zn, copper (Cu), nd mngnese (Mn) hve fungicidl properties. Distinguishing etween fungicidl nd nutritionl responses with the use of folir nutrients is difficult. Tle 13. Influence of oron pplictions on nnul ryegrss seed yield, flg lef oron concentrtion, nd oron soil test level. Boron rte Soil test B Flg lef B Seed yield (l/) Soil (ppm) (ppm) (l/) 0 Dyton 0.2 10 2,143 1.25 0.5 39 2,123 0 Awrig 0.1 9 2,098 1.25 1.4 42 1,999 Boron pplied in Mrch 2000 s dry grnulr fertilizer mixed with ure. Soil nd plnt smples tken My 24, 2000. For more informtion Fertilizer nd Lime Mterils Fertilizer Guide, FG 52-E (revised 1990). http://extension.oregonstte.edu/ctlog/ pdf/fg/fg52-e.pdf Reserch on which this puliction is sed 1953, 1954, nd 1983 1985: Seed yield ws mesured on plots receiving rnge of N rtes. Dt is presented in Figure 6 (pge 6). 1995: Recycled pper residue t 35 t/ ws pplied to two frms ner Hrrisurg, Oregon in Septemer. Soil ph nd C incresed with ppliction of the pper wste, ut yield ws reduced n verge of 270 l/. Lower rtes thn used here re suggested to provide desired soil ph increse nd lessen yield reduction. 1996 nd 1997: Volunteer seedlings were used to estlish plots. Yield of solid stnd ws lower thn tht of stnd treted with glyphoste to crete rows. Highest yields were mesured with 25 percent stnd remining. 1995 1997: Annul ryegrss ws estlished y conventionl tillge nd drilling, no-till plnting, nd with volunteer seedlings where residue ws removed y ling or not removed nd flil chopped. The conventionl plowing nd drilling mintined 3-yer verge 5 percent yield dvntge over the no-till estlishment nd 16 percent over using volunteer seedlings to estlish the crop. 2000 nd 2001: Nitrogen ws pplied t rtes of 0 to 270 l/ t two sites. N rtes etween 90 nd 135 l/ produced the highest seed yield in three of the four sites. 2000: Tretments of 0 nd 1.25 B/ were pplied with spring N t two sites. Annul ryegrss seed yield did not increse with B ppliction. Figure 8. Weighing seed from plots in grower s field. 2003 2004: K 2 O rtes from 0 to 176 l/ nd Cl from 0 to 140 l/ were pplied to Gulf nnul ryegrss in the spring. Soil test K ws dequte (138 ppm), nd K did not increse seed yield. Chloride ppliction incresed seed yield one yer. No method exists to predict Cl need, nd routine ppliction of KCl for Cl is not recommended. See Spring potssium nd chloride ppliction (pge 9). 2005 2008: Preplnt rodcst nd incorported lime ws compred to 150 l lime/ nded t plnting, nd yield ws mesured on Dyton soil ner Hlsey, Oregon. All lime tretments incresed seed yield. The 3-yer verge seed yield for tretments receiving 150 l/ lime nded t plnting were sttisticlly the sme s 2.5 nd 5 t/ lime incorported t the eginning of the study. Photo: Mrk Mellye 10
References Brown, W.G., T.L. Jckson, nd H.W. Youngerg. 1975. Appliction of Nitrogen for Grss Seed Production Does It Still Py? Oregon Stte University Extension Service. Specil Report 435. Chpin, M.F. nd J.H. Huddleston. 1992. Effects of nnul ryegrss residue mngement on Dyton soil orgnic cron distriution nd relted properties. In: W.C. Young III (ed.), 1991 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 89. Fitzgerld, M.H., M.E. Mellye, nd D.M. Sullivn. 1998. Liming with recycled pper residue (RPR). In: W.C. Young III (ed.), 1997 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 111. Griffith, S.M., S.C. Aldermn, nd D.J. Streeter. 1997. Itlin ryegrss nd nitrogen source fertiliztion in western Oregon in two contrsting climtic yers. Growth nd seed yield. J. Plnt Nutrition 20(4&5):419 428. Hrt, J.M., M.E. Mellye, G.A. Gingrich, W.C. Young III, T.B. Silerstein, nd N.W. Christensen. Spring potssium nd chloride ppliction for grss seed production in the Willmette Vlley. 2005. In: W.C. Young III (ed.), 2004 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 124. Hrt, J.M. nd M.E. Mellye. 2010. Annul ryegrss seed production in cidic soil. In: W.C. Young III (ed.), 2009 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 129. Jckson, T.L. 1956. The effect of time nd rte of nitrogen ppliction on seed production of common ryegrss. In: Proc. 7th Annul Fertilizer Conference of the Pcific Northwest, June 28 30, Ykim, WA. Jckson, T.L. 1984. Strw decomposition nd disese suppression. Report to Field Burning Commission on Intergency Agreement, DEQ Contrct No. 15-84, Septemer 28. Jckson, T.L. nd N.W. Christensen. 1985. Nitrogen fertilizer effects on strw decomposition nd old crown growth. Report to Field Burning Commission on Intergency Agreement, DEQ Contrct No. 10-85, Octoer. Mellye, M.E., W.C. Young III, T.G. Chstin, T.B. Silerstein, nd C.J. Gricek. 1998. The effect of strw removl nd different estlishment systems on soil fertility levels in nnul ryegrss seed fields. In: W.C. Young III (ed.), 1997 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 111. Mellye, M.E. 1997. Effect of recycled pper residue soil mendment (RPR) on ryegrss seed yields. In: W.C. Young III (ed.), 1996 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 110. Mellye, M.E. nd L. Gerig. 2002. Row Sprying Volunteer Ryegrss. Oregon Stte University Extension Service. FS 7. Mellye, M.E., G.A. Gingrich, nd J.M. Hrt. 2001. Do grss seed fields in the Willmette Vlley need oron fertilizer? In: W.C. Young III (ed.), 2000 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 115. Young III, W.C. 1981. Grzing durtion effects on seed yield of nnul ryegrss (Lolium multiflorum L.). M.S. thesis. Oregon Stte University. Young III, W.C., T.G. Chstin, M.E. Mellye, T.B. Silerstein, nd C.J. Grcik. 1997. Crop residue mngement nd estlishment systems for nnul ryegrss seed production. In: W.C. Young III (ed.), 1996 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 110. Young III, W.C., T.G. Chstin, M.E. Mellye, T.B. Silerstein, nd C.J. Grcik. 1997. Estlishment of rows in volunteer nnul ryegrss seed crops using shielded spryer. In: W.C. Young III (ed.), 1996 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 110. Young III, W.C., T.G. Chstin, M.E. Mellye, T.B. Silerstein, nd C.J. Grcik. 1998. Crop residue mngement nd estlishment systems for nnul ryegrss seed production. In: W.C. Young III (ed.), 1997 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 111. Young III, W.C., D.O. Chilcote, nd H.W. Youngerg. 1996. Annul ryegrss seed yield response to grzing during erly stem elongtion. Agronomy J. 88(2):211 215. Young III, W.C., M.E. Mellye, G.A. Gingrich, T.B. Silerstein, T.G. Chstin, nd J.M. Hrt. 2001. Defining optimum nitrogen fertiliztion prctices for grss seed production systems in the Willmette Vlley. In: W.C. Young III (ed.), 2000 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 115. Young III, W.C., M.E. Mellye, G.A. Gingrich, T.B. Silerstein, T.G. Chstin, nd J.M. Hrt. 2002. Defining optimum nitrogen fertiliztion prctices for fine fescue nd nnul ryegrss seed production systems in the Willmette Vlley. In: W.C. Young III (ed.), 2001 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 121. Young III, W.C., B.M. Queemn, M.E. Mellye, nd C.J. Grcik. 1995. Row sprying volunteer nnul ryegrss seed crops. In: W.C. Young III (ed.), 1994 Seed Production Reserch t Oregon Stte University, Deprtment of Crop nd Soil Science, Ext/CrS 102. Acknowledgments We thnk the following for thoughtful dvice nd ssistnce during the preprtion of this puliction: Dr. Mrvin Kuffmn, consultnt (first edition); Pt Boren, Crop Production Services; nd Peter Kuenzi, Wilur-Ellis Compny (first nd second editions). 2011 Oregon Stte University. This puliction my e photocopied or reprinted in its entirety for noncommercil purposes. This puliction ws produced nd distriuted in furthernce of the Acts of Congress of My 8 nd June 30, 1914. Extension work is coopertive progrm of Oregon Stte University, the U.S. Deprtment of Agriculture, nd Oregon counties. Oregon Stte University Extension Service offers eductionl progrms, ctivities, nd mterils without discrimintion sed on ge, color, disility, gender identity or expression, mritl sttus, ntionl origin, rce, religion, sex, sexul orienttion, or vetern s sttus. Oregon Stte University Extension Service is n Equl Opportunity Employer. Pulished Decemer 2003. Revised Ferury 2011.