Long Term Trends. ALFALFA testing. Alfalfa Management for the UP Kim Cassida 3/14/2016. Total MSU Forage Test Entries, 1992 to 2015

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1 //6 Alfalfa Management for the UP Long Term Trends ALFALFA testing Total MSU Forage Test Entries, 99 to 5 Long term Alfalfa Test Trends Alfalfa Grass Annuals Other Avg Alfalfa Yield in First Production Years 8 8 Number of Entries Avg Annual DMY, ton/a/yr NASS EL avg LC avg UP Avg UP Best UP Worst Year Seeded UP Vernal Performance of Vernal Relative to Best New Variety The Value of a Better Variety How much is an extra ton of worth? DMY, % of Vernal East Lansing Lake City Chatham Over the past years, the BEST has YIELDED MORE than Vernal: ~.. tons/yr Southern MI and Thumb ~.5 tons/yr Northern MI and UP Current hay price ~ $ 5/ton in Michigan + ton/acre/yr X yrs = +$5 (S. MI) / $5 (N) tons of hay is +$ /acre/yr (S. MI) / $57 (N) over four years ( production years plus seeding year)

2 //6 Disease Resistance Ratings, Winterhardiness, & Fall Dormancy FALL DORMANCY (FD) RATING = tendency to stop growing as daylength and temperature decrease a. Rated as = extremely dormant to = extremely non dormant b. Michigan FD rating to 6 recommended ( to for UP) c. Lower FD score also reduces spring and summer regrowth rate d. Trade off: faster regrowth (higher FD score) allows more cuttings per year and greater total yield for early stand years, but often reduces stand life WINTER SURVIVAL INDEX (WSI) a. Winter hardiness is not as tightly linked to fall dormancy trait as previously thought b. WSI rates varieties from (superior survival) to 6 (no survival) Non dormant Regrowth of differing in fall dormancy, 7 days postharvest during the growing season Dormant Annual is simply nondormant plus poor winter survival Yellow Flower Alfalfa Update What s the Scoop on Reduced Lignin Alfalfa? Released in 5 as Sholty (SDSU, NRCS, and MSU) Foundation seed fields planted in 5 in South Dakota Why do we care how much lignin is in forage? Lignin has negative nutritional value Greater lignin decreases forage digestibility through physical interference with fermentation Cell wall, including lignin, increases as forage plants mature Proportion of lignin increases faster than digestible cell wall components Alfalfa typically contains 5 % lignin What is lignin? Lignin is a phenolic secondary compound found in plant cell walls Cell walls consist of a framework of cellulose and hemicellulose strands in a matrix of lignin Lignin is required for plant function & survival Gives rigidity and strength to cell wall Contributes to normal growth patterns Enhances water transport in plant by reinforcing xylem vessels May help reduce water content of cell walls Provides resistance to attack by pests & diseases NDF (Cell Wall) NDF Solubles Protein Sugar Starch Fat Pectin Organic acids Cellulose, LIGNIN, Hemicellulose

3 //6 8 Lignin is a key part of the Yield Quality Tradeoff As matures, DMY increases while nutritive quality and value decrease Percent of DM Value Veg Bud / Late bloom bloom Growth Stage RFV $/Ton Seed pod CP ADF NDF DDM Cutting Alfalfa at bud stage for optimum quality prevents complete recharge of root carbohydrates Reduced persistence Veg Bud / Late Seed bloom bloom pod Growth Stage Development of Reduced Lignin Alfalfa Variety name Hi Gest HarvXtra Development and Marketing Team Alforex Seeds (Dow Agrosciences) Forage Genetics Int l Monsanto Noble Foundation ARS Dairy Forage Lab Origin Conventional breeding GMO (turn OFF existing gene) Stacked traits None Roundup Ready Seed Availability 5 (Limited supply) 6 (Limited supply) Marketing Claims 7 % less lignin 7 day longer cut interval Technology fee No Yes % less lignin 7 day longer cut interval points more RFQ Percent of Maximum Yield 8 6 RFQ normal YIELD Days of Regrowth Optimum date Optimum normal date RL RFQ reduced lignin Theoretical Reduced Lignin Advantage RFQ > 85 RFQ < Equal annual yield and quality in fewer harvests with better persistence? Unanswered Questions??? How will it yield? Is there a yield drag? Limited plot data What is the ideal harvest schedule? 7 days longer? Will it lodge? Small plot data promising Will there be pest/disease problems? Limited data Will lignin reduction be consistent? Limited data How will it feed? Will there be enough effective fiber? Are ration adjustments needed? Limited animal feeding data Reduced lignin Alfalfa Research at MSU Sponsored by FGI 5 states participating CA, KS, MI, PA, WI HarvXtra and two RR ready controls Planted May, 5 Seeding year data collected in 5 ( regrowth cuts) Trial Harvest Timing ) Harvest at 8,, or 8 d intervals ) Yield and quality measured Trial Scissors Clip Trial ) Harvested six times from to 7 d of growth ) Forage quality measured

4 //6 Scissors Clip Trial MSU Forage Quality Seeding Year 5 (preliminary results) Alfalfa Harvest Schedules 8 days days 8 days Lignin, % 6 5 Sept cut LSD =.9 HarvXtra Pioneer 5R WL55RR Oct cut LSD = Days since last cut NDF Digestibility, % Sept cut LSD =.87 HarvXtra Pioneer 5R WL55RR Oct cut LSD = HarvXtra Days since last cut RFQ, % 5 Sept cut LSD = 8.9 Pioneer 5R WL55RR Oct cut LSD = HarvXtra consistently better quality than controls BUT seedling MSC never exceeded vegetative stage, resulting in unrealistically high quality Days since last cut Forage Yield Seeding Year 5 (preliminary results) Harvest schedule timing did not affect DMY in the seeding year all DMY relatively low Reduced lignin variety yielded ~5% less than controls in both cuttings Forage Quality Seeding Year 5 (preliminary results) Reduced lignin variety had consistently better NDFd and greater RFQ than controls in both cuttings. Lignin was reduced only in the Sept cutting. Vegetative maturity stage resulted in exceptionally high forage quality. Variety Cut (Sept) Cut (Oct) Total tons/acre Pioneer 55R.a.58a.67a WL55RR.7a.5a.59a HarvXtra8.9b.b.b LSD.7.9. Cut (Sept) Cut (Oct) Variety Lignin % NDFD % RFQ Lignin % NDFD % RFQ Pioneer 55R.8a 55.8b c.6 7.6b b WL55RR.5b 57.b 5b.8 7.6b 7b HarvXtra8.c 6.a 95a.5 76.a 6a LSD ns.66 Forage Quality Seeding Year 5 (preliminary results) Lengthening the harvest interval increased lignin while decreasing NDFD and RFQ Establishment Cut (Sept) Cut (Oct) Harvest Timing Lignin % NDFD % RFQ Lignin % NDFD % RFQ 8 days.5c 6.a a.8c 76.a 7ab days.7b 56.7b 8b.b 7.9ab 5a 8 days 5.a 55.5b c.7a 7.b 6b LSD

5 //6 Good field sites for Alfalfa are:. Well drained Good field sites for Alfalfa are:. Well drained. Soil ph > 6.8. Deep soil. Good fertility (K, P, S, B) 5. No autotoxicity Autotoxicity Alfalfa is toxic to its own seedlings a. Specific toxic compound unknown (probably a combination of things) b. Toxin concentrated in above ground tissue c. Toxin is water soluble, leaches out of soil over time d. Soil type affects duration of effect (sandy soil clears faster than heavy soil) e. Negative effect persists wk to yr after an stand is killed f. Effects of autotoxicity. Reduced seedling germination within 8 in diameter of a mature (has flowered) plant. Permanent damage to structure of seedling roots. AUTOSUPPRESSION even if stand looks ok, damaged roots lead to reduced lifetime stand productivity g. Avoiding problems. Don t overseed into existing stands. Safest plan Rotate out of for at least one year before replanting. Use tillage to speed toxin breakdown Good Establishment is Vital to Stand Productivity Yield (% of st Prodtn Year) Yield as Stand Ages Age of Stand (Years) Stems per Square Foot seedyr 5 6 DM Yield, % of Max Stem Density & Yield 8 6 D.W. Meyer. 8. Seeding Rate Effects in Alfalfa. North Dakota State University Alfalfa Seeding Rate Plant 6 lb/acre ~75 seeds per square foot Ideal at least 75 seedlings emerged No data support economic value (yield, quality, or persistence) for seeding rates > 6 lb/acre Plant RR at the same seeding rate as conventional (Hall et al., ; ) % Emergence 5 Effect of Seeding Depth on Alfalfa Emergence clay loam sand Seeding Depth (inches) Planting too deep is the single most common reason for establishment failure Firm, level seedbed is optimum 5

6 //6 Controlling Null Plants in RR Alfalfa A null plant does not have the RR trait (up to % of seeds) In a new seeding, there will be 75 plants/ft and about 8 nulls/ft Stand will continually self thin down to 5 plants/ft at the end of its economic life you do not want these survivors to be nulls Terminating RR Alfalfa Failure to kill RR plants is problematic if succeeding crop in rotation is also RR Best results in the Forage Program: fall applied, D and dicamba combination PLUS tillage Apply glyphosate at or before th trifoliate leaf to remove the nulls before they can win the competition with neighbors Fertility Sulfur More than half of Michigan stands surveyed by MSUE in 5 were deficient or low normal in plant tissue sulfur Sulfur fertilizer may pay on sandy or low organic matter soils Maps: National Atmospheric Deposition Program (from 5) Nutrient Nutrient Removal by Alfalfa Hay Crop ton hay (8% DM) ton DM MI State avg.5 ton DM/yr MSU Variety Test 7 ton DM/yr K O P O S 7 6 Does RR Alfalfa need extra TLC? RRA High Yield Management Trial Sponsor: Monsanto Popular criticisms of glyphosate use include:. glyphosate induced tie up of soil micronutrients. increased pathogen pressure on crop So what happens if we apply extra micronutrients and pesticides? RESULTS: On fertile soil, apply extra PKS+B, foliar micronutrients, insecticide, fungicide, and Bioforge: Nothing improved DMY unless was stressed by hot, dry weather in midsummer cuttings Did not improve lifetime stand DMY Unlikely to be cost effective 6

7 //6 Questions? 7