Fruit, Vegetable & Farm Market EXPO Michigan Greenhouse Growers EXPO December 7-9, 2010 DeVos Place Convention Center, Grand Rapids, MI

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1 Gret Lkes Fruit, Vegetble & Frm Mrket EXPO Michign Greenhouse Growers EXPO December 7-9, 1 DeVos Plce Convention Center, Grnd Rpids, MI Asprgus Where: Gllery Overlook (upper level) Room C & D Recertifiction credits: (1B, PRIV OR COMM CORE) CCA Credits: SW(.5) PM(.5) CM(.5) Modertor: John Bkker, Michign Asprgus Advisory Bord, Dewitt, MI 9:.m. Asprgus Miner Reserch Zsofi Szendrei, Entomology Dept., MSU 9:.m. Irrigtion nd Cover Cropping Effects on Soil Moisture nd Weeds in Asprgus Dniel Brinrd, Horticulture Dept., MSU 9:5.m. Asprgus Disesee Reserch Updte Brin Cortright, Plnt Pthology Dept., MSU Mry Husbeck, Plnt Pthology Dept., MSU 1:1.m. Asprgus Replnt Suppression Reserch Mthieu Ngoujio, Horticulture Dept., MSU 1:3.m. Grower Experiences With Third Prty Audits Ben Byl, Grower, Shelby, MI Mike Vn Agtmel, Vn Agtmel nd Sons, Hrt, MI Scott Boundy, Greiner Frms, Inc., Hrt, MI 1:5.m. Michign Asprgus Advisory Bord Updte John Bkker, Michign Asprgus Advisory Bord, Dewitt, MI

2 Asprgus Miner Reserch ZsofiSzendrei nd Willim R. Morrison III Deprtment of Entomology, Michign Stte University, Est Lnsing, MI, 88 Lb website: Reserch in the vegetble entomology lb focuses on integrted pest mngement of the sprgus miner (Ophiomyi simplex (Loew), Dipter: Agromyzide; Figure 1). This insect is puttive vector for pthogenic species of Fusrium fungus, which is the custive gent for erly decline syndrome in sprgus fields. Figure 1. Asprgus miner lrvl dmge on n sprgus stem (left); sprgus miner pup (middle); sprgus miner dult (right). Photos re not to scle. Photos by R. Morrison. Insecticide tril.the MSU vegetble entomology lb conducted n insecticide tril in n experimentl sprgus field in Hrt, MI in summer 1. We hd nine insecticide tretments including six products nd tested three ppliction methods (chemigtion through drip irrigtion, folir spry, nd in-furrow t plnting). The sprgus crowns were plnted My 19, 1 nd the drip irrigtion system ws set up June 1, 1. The only currently registered insecticides in sprgus s used in this tril, re Sevin F nd Rdint SC. Folir nd drip tretments were pplied twice during the seson. Smpling for sprgus miner nd sprgus beetle ws done by visully surveying nd recording the number of dmged stems or insect life stges weekly on stems per tretment. Drip irrigtion ws used only for chemigtion (i.e. plots were not wtered throughout the summer), but plots tht were not ssigned to chemigtion tretment received equl mounts of wter through the drip system s those receiving chemigtion tretment. Chemigtion ws ble to suppress sprgus miner dmge (Figure ) ndsprgus beetle eggs (Figure 3) nd lrve (Figure ). In generl, insecticides pplied through drip irrigtion performed the best for insect pest suppression, followed by folirly pplied products. In furrow, t plnting pplictions were the lest effective in controllingsprgus miner nd beetles. Since the sprgus field ws estblished this yer, pest pressure in generl ws t low levels especilly erly in the seson. This is likely becuse pests need some time to immigrte into nd colonize new fields.

3 Figure. Asprgus miner dmge on sprgus stems on scle of -5.( - no dmge; 5 - severe dmge). Figure 3. Averge sprgus beetle egg bundnce in our experimentl sprgus plot.

4 Figure. Asprgus beetle lrvl bundnce in our experimentl sprguss plot. Field monitoring of sprgus miner.in the 1 field seson we monitored the bundnce of sprgus miners by counting the dult flies weekly on yellow sticky trps plced t five commercil sprgus fields in the Hrt re. We observed pek in dult ctivity in mid- to lte-july, nd smller pek in the second hlf of August (Figure 5). Since the fll ws unusully wrm, prtil third genertion emerged, but these individuls re unlikely to be ble to complete their development before the freezing tempertures kill them. Yellow sticky trps plced t the field-edge cught more flies (sesonl verge: 7./trp) thn sticky trps inside the crop (sesonl verge: 5.5/trp). Trps plced t cnopy level ( feet from ground) cught more dult flies (sesonl verge: 1/trp) thn trps plced close to the soil surfce (sesonl verge: /trp). We re currently in the process of identifying nturlly occurring prsitoid species of the miner, s well s exmining their bundnce. So fr, prsitoids hve been identified from the Pteromlide(most bundnt prsitoids of miner), Eulophide nd Brconide fmilies (Figure 6). Fourty percent of the miner pupe collected from five commercil fields were infected with prsitoids. In the future, we will investigte wys in which their efficiency nd bsolute bundnce cn be incresed in order to better control sprgus miner popultions.

5 Figure 5. Averge of dult sprgus miners collected on yellow sticky trps in five commercil sprgus fields. Figure 6. Three different types of prsitoids were collected from sprgus miner pupe during summer 1 from commercil sprgus fields.

6 Irrigtion nd Cover Cropping Effects on Soil Moisture nd Weeds in Asprgus Dniel Brinrd, Deprtment of Horticulture, Michign Stte University AA Plnt nd Soil Sciences Building, Est Lnsing, MI 88 emil: phone: ext 117 ABSTRACT. Although sprgus is reltively drought tolernt, irrigtion my ply n importnt role in improving the resilience of sprgus to pests nd extreme wether events. Irrigtion my lso crete opportunities for integrtion of cover crops into sprgus production with reduced risk of competition for wter between sprgus nd the cover crop. Living mulches sown immeditely fter sprgus hrvest nd llowed to grow below the fern cnopy my help to suppress weeds while mintining nd improving soil chrcteristics. Reserch ws initited in Hrt, Michign in 8 with the following longterm objectives: 1) to evlute the effects of irrigtion on sprgus yields nd weed mngement under two cropping systems; nd ) to determine the effects of cerel rye (Secle cerele) living-mulch on soil moisture, weed growth, nd sprgus yield. After 3 yers, our results indicte tht: 1) rye living mulches grown without irrigtion cn reduce soil moisture content to levels tht re likely to stress sprgus fern; ) rye living mulches cn suppress weeds effectively when summers re cool (e.g. 9), but fil to dequtely suppress weeds under wrm conditions (e.g. 1); 3) irrigtion cn be used to overcome wter deficits cused by rye, but the long-term effects of irrigtion on sprgus yields in MI re not cler. More reserch is needed to optimize irrigtion nd living mulch systems, nd to help growers determine if the potentil benefits of these prctices justify the costs. INTRODUCTION Why irrigte? Drought stress my be n importnt fctor contributing to the decline in sprgus fern helth nd yield in recent yers. Although sprgus is deep rooted nd reltively drought tolernt, soil wter content during fern growth is n importnt determinnt of crop yields (Drost nd Wilcox-Lee, 1997; Drost 5; Hrtmn 1981; Roth nd Grdner 199). Drought stress during fern growth cn limit the cpcity of plnts to produce the soluble crbohydrtes in roots necessry for high yields in subsequent sesons (Drost 1997). Stressed plnts my lso be more susceptible to fungl diseses which incresingly plgue the sprgus industry (Husbeck, personl communiction). Wrmer tempertures nd more vrible rinfll ptterns observed in MI in recent yers re predicted by climte models to continue, mking irrigtion n incresingly importnt tool for reducing risks of yield loss in sprgus production. Irrigtion nd cover crops. Irrigtion my lso open opportunities for greter integrtion of cover crops into sprgus production systems. In irrigted systems, cover crops growing below the fern cnopy my be more relibly estblished with reduced risk of competition for wter with the sprgus crop. These living mulches my provide severl importnt benefits. During extreme rinfll events, they cn protect the soil from degrdtion, reduce the risks of nutrient nd pesticide run-off, nd tke up excess moisture tht cn be s dmging to the sprgus crop s drought (e.g. Wilson et l 1996; Hrtmnn 199). Living mulches my lso provide rnge of other benefits including mitigtion of soil compction, increses in soil orgnic mtter, improved nutrient cycling, nd reductions in the incidence of insect pests (Andow et l 1996; Vndermeer 1989).

7 Living mulches nd weeds. The impct of living mulches on weeds nd sprgus is uncler. On the one hnd, if poorly mnged, living mulches re themselves weeds: competing with the crop for nutrients, wter or light, nd cting s potentil hosts for diseses nd insect pests. The presence of rye lso complictes weed mngement since severl herbicides commonly used for suppression of weeds re not comptible with rye. On the other hnd, crefully selected nd mnged living mulches my suppress weeds without suppressing the crop. Rye living mulches, sown following sprgus hrvest hve been recommended (e.g. Kuepper nd Thoms, 1) nd tried by growers, but few studies hve been conducted to evlute their impct on sprgus or weeds (Pine et l. 1995). When sown in the summer, winter rye cn emerge rpidly nd suppress weeds, but does not shde crops due to its short growth hbit in the bsence of vernliztion (Brinrd nd Bellinder, ). Objectives. With these issues in mind, field studies were initited in 8 with the following longterm objectives: 1) To evlute the effects of irrigtion on sprgus yields nd weed mngement under two cropping systems nd ) To determine the effect of rye living mulch on soil moisture, sprgus yield, nd weed mngement. METHODS A field tril ws initited t the Asprgus Reserch Frm in Hrt, MI in sprgus (cultivr Jersey Gint ) tht hd been estblished from crowns in Following the finl sprgus hrvest in lte June, four experimentl tretments were estblished consisting of two different mngement systems (conventionl vs living mulch), ech with two levels of irrigtion (no irrigtion vs irrigtion) (Tble 1). The sme mngement systems were mintined in the sme plots ech yer from 8-1. Tble 1. Summry of tretments exmined Irrigtion Cover Tillge PRE herbicides 1. Herbicide/No irrigtion No None No Dul/Sprtn/Krmex. Herbicide/Irrigtion Yes None No Dul/Sprtn/Krmex 3. Living Mulch/No irrigtion No Rye Yes None. Living Mulch/Irrigtion Yes Rye Yes None Six replictes of ech tretment were included in plots mesuring 5 x 13.5, with 3 rows of sprgus spced.5 prt in ech plot. The herbicide system consisted of no-tillge with ppliction of tnk-mix of Roundup (1 Q/A), Dul (1.5 pt/a), Sprtn ( oz/a) nd Krmex (1. lbs/a). In the livingmulch system, winter rye (Secle cerele) ws brodcst t 3 bu/a nd roto-tiller ws used to simultneously kill weeds nd incorporte rye to depth of 1-. No residul herbicides were used in the living-mulch system, nd no post emergence herbicides were used in either system. Irrigtion ws ccomplished using 7 micro-sprinklers per plot to simulte overhed irrigtion. Soil moisture sensors (EC-5 sensors, Decgon Devices) were instlled t 6 nd in replictes of ech tretment to monitor soil volumetric wter content (VWC). Irrigtion ws used initilly to estblish rye, nd then to mintin VWC t or bove 5% of vilble wter through the middle of August. On the sndy soils of the experimentl site, field cpcity ws pproximtely 11% VWC nd the permnent wilting point pproximtely 5% VWC t depth. Weed density, rye dry weight, rye number nd fern stem number were ssessed in erly September. Weed density ws evluted by counting the number of weeds greter thn 1 in height (for erect weeds) or dimeter (for rosette/spreding weeds) in the entire plot. Asprgus yield ws ssessed from the middle row of ech plot during 18 hrvest events in spring 9 nd 5 hrvest events in spring 1.

8 RESULTS Irrigtion, rinfll nd soil wter content. Without irrigtion, soil VWC t in rye living mulch tretments ws pproximtely % below the bre soil tretment during August (6-8 wks fter sowing) (Figure 1), resulting in prolonged periods ner the permnent wilting point in 8 nd 9. In irrigted tretments, VWC ws mintined t or bove 5% vilble wter (8% VWC), with the exception of 8, when VWC fell to -5% in ll tretments by lte August, before hevy rinfll nd cool tempertures in September restored VWC to field cpcity. In 8 nd 9 VWC rnked in the following order: Bre+irrigtion > Bre = Rye+irrigtion > Rye. In 1, stedy rinfll throughout the summer resulted in little need for irrigtion, nd few differences in soil VWC between tretments. Living mulch filed to control summer nnul weeds fter 3 yers. The dominnt weed species during fern growth were Powell mrnth (Amrnthus powellii) nd sndbur (Cenchrus longispinus). In 8, densities of sndbur were slightly higher in rye living mulch compred to herbicide tretments (Tble 1). In 9, cooler conditions resulted in more vigorous rye growth, nd both weed species were suppressed by rye, resulting in no differences in weed density between tretments. However, in 1, densities of both Powell mrnth nd sndbur were much higher in rye living mulch tretments compred to herbicide tretments. Filure of rye living mulch to suppress weeds in 1 ws likely the result of 1) poor rye estblishment due to unusully high tempertures in 1, nd ) higher weed seedbnks of these species resulting from higher weed seed production in previous Soil VWC (%) Soil VWC (%) Soil VWC (%) /1 7/1 7/19 7/8 8/6 8/15 8/ 9/ Bre Rye Bre + Irrigtion Rye + Irrigtion 7/9 7/18 7/7 8/5 8/1 8/3 9/1 9/1 9/19 Bre Rye Bre + Irrigtion Rye + Irrigtion Bre Rye Bre + Irrigtion Rye + Irrigtion 6/ 7/1 7/1 7/19 7/8 8/6 8/15 8/ 9/ 9/11 9/ yers. Although Powell mrnth could hve been controlled with n ppliction of post-emergence herbicide like Snde, grsses like sndbur pose chllenge in fields where rye living mulches re used, since grminicides tht kill sndbur, would lso likely kill the rye living mulch. Dte A. 8 B. 9 C. 1 Figure 1: Rinfll (blue brs), irrigtion (green brs) nd soil volumetric wter content (VWC) t ", Hrt, MI, 8 (A), 9 (B) nd 1 (C) Rinfll nd irrigtion (inches) Rinfll nd irrigtion (inches) Rinfll nd irrigtion (inches)

9 Tble. Effects of irrigtion nd rye on weeds in lte summer, 8-1 Herbicide/no-till Not irrigted.1 b..1 c.8 b.1.11 c.3 b.13. b Irrigted.8 b.6.6 b.9 b.9. b.1 b.18. b Rye (June) /till 8 Totl Powell mrnth b Sndbur Plnts/m Not irrigted.58 b b Irrigted b Note: Only weeds greter thn 1' in height or dimeter were included Column mens with letter in common re not significntly different (Fisher LSD Method; P=.5) Living mulch helped suppress mrestil but not sndbur when herbicides dissipted. The dominnt weed species during sprgus hrvest were mrestil (Conyz cndensis), sndbur nd Powell mrnth in 1 (Figure ). In 8 nd 9, ll three species were well controlled with stndrd combintion of burndown nd preemergence herbicides pplied in erly spring. However, in 1, PRE herbicides filed to provide dequte control nd differences in weed popultions under rye living mulch nd herbicide tretments were redily pprent by erly June. Under these circumstnces, mrestil popultions were lower where rye living mulch ws grown, while sndbur popultions were higher (Figure ). The suppressive effect of rye living mulch on mrestil in 1 ws likely due to the presence of hevy rye residue in lte summer of 9, which prevented mrestil from estblishing successfully. Rye living mulch hd similr suppressive effect on dndelion, lthough dndelion did not become problem in sprgus during this study. Weed density (plnts/m) Conventionl Living mulch Powell mrnth Sndbur Mrestil 1 Figure : Effects of rye living-mulch on weeds during sprgus hrvest, 1. Asprgus yields were not ffected. Neither irrigtion nor rye living mulch hd ny detectble effect on sprgus yield in the 9 nd 1 sesons (Figure 3). However, lrge vribility in fern helth cross the experimentl site mde it difficult to dequtely ssess yield effects. Our soil moisture dt suggests tht rye living mulch (without irrigtion) increses the risk of drought stress of sprgus fern during lte summer. In wrm yers (like 1), rye living mulch is lso unlikely to dequtely suppress summer nnul weeds, thus posing risks of weed-sprgus competition unless supplementl herbicides re used. On the other hnd, rye living mulches used in combintion with irrigtion pose fewer risks, Asprgus yield (lbs/a) 6 Not irrigted Irrigted Bre (No-till/Herbicides) N.S. Rye (Till/No herbicides) Figure 3: Effects of irrigtion nd rye living-mulch on verge sprgus yield, 9-1.

10 nd my benefit sprgus through increses in soil orgnic mtter nd reductions in soil erosion. Long term reserch is needed to better understnd the potentil effects of living mulches nd irrigtion on sprgus. Reserch ssessing lterntive cover crop species, different methods of irrigtion (e.g. subsurfce drip) nd complementry weed mngement prctices my prove beneficil for improving the resilience of sprgus to stress nd incresing frm profitbility. LITERATURE CITED Andow, D. A., A. G. Nicholson, H. C. Wien, nd H. R. Willson Insect popultions on cbbge grown with living mulches. Env. Entomology 15: Brinrd, D. C. nd R. R. Bellinder.. Weed suppression in broccoli-winter rye intercropping system. Weed Science 5: Drost, D. T. 5. Improving sprgus growth through better wter mngement. Gret Lkes Fruit nd Vegetble EXPO Proceedings. Drost, D. T. nd D. Wilcox-Lee Soil wter deficits nd sprgus: II. Bud size nd subsequent sper growth. Scienti Horticulture 7: Hrtmnn, H. D The influence of irrigtion on the development nd yield of sprgus. Act Horticulture 119: Kuepper, G. nd R. Thoms. 1. Orgnic Asprgus Production. Current Topic. Approprite Technology Trnsfer for Rurl Ares. Ntionl Center for Approprite Technology. Pine, L., H. C. Hrrison nd A. C. Newenhouse Estblishment of sprgus with living mulch. Journl of Production Agriculture 8: 1-. Vndermeer, J The Ecology of Intercropping. New York: Cmbridge Univ. Press. 37 p. Wilson, D. R., S. M. Sinton nd H. A. Frser-Kevern Irrigtion responses of estblished sprgus Proceedings VIII Interntionl Symposium on Asprgus. ACKNOWLEDGEMENTS. Funding for this reserch ws provided by MAES Project GREEEN nd Michign Asprgus Reserch, Inc. Thnks to Norm Myers, John Bkker nd Steve Dillinghm for vluble dvice nd ssistnce with this project, nd to Corey Noyes, Ben Byl nd Dryl Lederle for technicl support.

11 Asprgus Disese Reserch Updte Dr. M.K. Husbeck ( ), nd B.D. Cortright Michign Stte University, Deprtment of Plnt Pthology, Est Lnsing, MI A new system of sprgus production needs to be dopted to ensure tht newly estblished fields remin vible nd productive to provide n dequte return on estblishment investment. This new system will rely on the use of clen crowns grown in properly fumigted fields. Additionl mesures for crown disese mngement re lso needed to extend field productivity. Soking crowns in effective fungicides prior to plnting my help limit disese on newly-plnted crowns. Fumigtion of production fields will help reclim fields tht hve history of high levels of disese. Controlling folir pthogens nd limiting insect dmge tht defolites the fern will ensure tht fern growth hs time to rechrge the crown for next hrvest seson. Proper rottion of crops nd mngement of soil ph nd soil moisture cn help keep crowns vigorous nd tolernt to infection. Using herbicides tht re sfe on crown nd fern growth hs recently been the focus of new MSU studies. Reserch hs been nd is currently being conducted on commercil frms to increse the wreness of the benefits multi-fceted pproch cn hve for incresing yields nd long-term productivity. Fumignt nd Crown Sok Tril. An ongoing experiment evlutes crowns grown in fumigted seedbeds in combintion with fungicides soks prior to plnting in production fields for control of Fusrium crown nd root rot nd Phytophthor sper, crown nd root rot of sprgus (see tble below). This tril ws plnted in 7 in commercil field with crowns grown during previous nursery fumigtion study. The crowns were rted nd plnted in the spring of 7 nd the growth of ech tretment monitored nnully. This ws the first yer of full hrvest for the plot Bsed on previous long term studies, differences in fern growth re expected fter the 11 hrvest. The crowns grown in the Telone C35 treted soil hd low percentge of Fusrium infected crowns t the time of plnting. Tretment of crowns in nursery Fern number per ft Fern number/a Unfumigted * 73,965 Unfumigted 7, + Cnnonbll 5WP.5 oz/1 gl (crown sok) Telone C gl/a ,715 Telone C35 35 gl/a 79,715 + Cnnonbll 5 WP.5 oz/1 gl (crown sok) K-Pm 6 gl/a ,11 K-Pm 6 gl/a + Cnnonbll 5 WP.5 oz/1 gl (crown sok) ,77 * There were no significnt differences mong tretments (Fisher LSD Method; P=.5). 9-Plnted Herbicide Study. In Spring of 1, second ppliction of tretments ws mde to the sprgus herbicide study estblished in 9. This ws the second yer of the plnting nd tretments were pplied right fter mowing of the existing fern nd finl soil leveling of the field.

12 Herbicide dmge ws noticed on the Cllisto nd Sprtn tretments which were ttributed to the ppliction of these herbicides. Weed competition ws light within these sme tretment plots. Stnd reduction in the Buccneer Plus tretment plot nd untreted control ws likely due to second yer of high weed pressure. This ws the second yer tht Cllisto ppliction resulted in reduced sprgus stnd. The grower stndrd ws included for comprison nd included Sprtn.31 pt + Sencor.5 lb + Dul Mgnum 1.5 pt + Buccneer Plus 3 pt. Stnd (%) Herbicide Sfety on Asprgus (second yer ppliction to 9-plnted crowns) de b b -c 11 Jun -d -d -e b-e b-e c-e e Untreted Sencor 75DF.66 lb Sinbr 8WP.5 lb Grower Stndrd Krmex 8DF 1 lb Lorox 5DF 1.5 lb Solicm 8DF 1 lb Snde 75WG.6 lb Buccneer Plus EC 3 pt Sprtn FL.5 pt Dul Mgnum 7.6EC 1.33 pt Cllisto SC.19 pt Weed cover (%) 3 1 Untreted Herbicide Sfety on Asprgus (second yer ppliction to 9-plnted crowns) e Grower Stndrd Sprtn FL.5 pt Snde 75WG.6 lb Cllisto SC.19 pt Tretments pplied pre-emergence. Brs with letter in common re not significntly different. -c b b -c Sencor 75DF.66 lb Sinbr 8WP.5 lb Dul Mgnum 7.6EC 1.33 pt Lorox 5DF 1.5 lb b-d Solicm 8DF 1 lb c-e Krmex 8DF 1 lb 11 Jun de Buccneer Plus EC 3 pt Grower Stndrd Progrm: Sprtn.31 pt Sencor.5 lb Dul Mgnum 1.5 Pt Buccneer Plus 3 pt

13 Fern height (in.) Untreted Herbicide Sfety on Asprgus (second yer ppliction to 9-plnted crowns) b-d Sinbr 8WP.5 lb Lorox 5DF 1.5 lb b Buccneer Plus EC 3 pt -c Solicm 8DF 1 lb -c Grower Stndrd Krmex 8DF 1 lb -c -c -c Sencor 75DF.66 lb Snde 75WG.6 lb Dul Mgnum 7.6EC 1.33 pt Sprtn FL.5 pt Cllisto SC.19 pt 1-Plnted Herbicide Study. The herbicides were pplied immeditely fter crown plnting nd well before fern emergence. Asprgus in res of lighter soil nd in res where plnting trenches were still visible showed more signs of herbicide dmge. These trenches llowed n herbicide buildup fter surfce wter wshed the product into the trenches. Mny of the herbicide tretments killed over % of the brley cover crop. The site ws fumigted with metm sodium nd this, combined with the herbicides, provided seson-long weed control for most tretments. Weeds observed in the untreted control, Buccneer Plus, nd Dul Mgnum tretments were comprised of brodlef types. The effect of vrious herbicides ws evluted by counting the number of fern in ' treted section of row. The grower stndrd ws included for comprison nd included Sprtn.31 pt + Sencor.5 lb + Dul Mgnum 1.5 pt + Buccneer 3 pt. This prticulr grower stndrd resulted in reduced stnd of fern tht ws significntly different thn the untreted plot nd to most other tretments. In ddition to reduced fern stnd, the fern in the grower stndrd ws dmged t n erly rting, but did grow out of the dmge lter. The Cllisto SC tretment lso resulted in dmged fern tht ws significntly different thn most of the other products included in the tril. cd d 11 Jun d Cover crop kill (%) Weed cover (%) Untreted 11 Jun 11 Jun c bc Prowl HO 3.8SC. pt Buccneer Plus EC 3 pt Herbicide Sfety on Asprgus (first yer ppliction to 1-plnted crowns) b bc Solicm 8DF 1 lb bc Lorox 5DF 1.5 lb b-d b-e Sprtn FL.5 pt Krmex 8DF 1 lb Dul Mgnum 7.6EC 1.33 pt c-e c-e Tretments pplied pre-emergence. Brs with letter in common re not significntly different. -c Snde 75WG.6 lb d-f Sencor 75DF.66 lb Chteu 51WDG.38 lb ef ef b Cllisto SC.19 pt Sinbr 8WP.5 lb f f Grower Stndrd

14 Dmged fern Dmged fern Untreted 6 My b 11 Jun Sinbr 8WP.5 lb Sencor 75DF.66 lb Herbicide Sfety on Asprgus (first yer ppliction to 1-plnted crowns) Prowl HO 3.8SC. pt Buccneer Plus EC 3 pt b Solicm 8DF 1 lb Tretments pplied pre-emergence. Brs with letter in common re not significntly different. b Sprtn FL.5 pt b Lorox 5DF 1.5 lb b Krmex 8DF 1 lb b Snde 75WG.6 lb -c Chteu 51WDG.38 lb Dul Mgnum 7.6EC 1.33 pt bc cd b Cllisto SC.19 pt d Grower Stndrd Dt shown for the studies in this report were collected erly in the growth seson. Lter evlutions were not used for this report due to the high incidence of fern deth from stem girdling cused by numerous sprgus miner lrve. Up to 15 pupe were recovered from single stem nd this outbrek ws seen in both Ocen nd Mson Counties. This mteril is bsed upon work supported by the USDA CSREES Specil Reserch Grnt Awrd , Subwrd 1138-G565. Any opinions, findings, nd conclusions or recommendtions expressed in this publiction re those of the uthor nd do not necessrily reflect the views of the USDA CSREES. This reserch ws lso supported by Michign Asprgus Reserch, Inc. We thnk our grower-coopertors Oomen Brothers Frms.

15 Introduction Asprgus Replnt Suppression Reserch Mthieu Ngoujio, Norm Myers, John Bkker, Jmes Counts, nd Drey Clrk Deprtment of Horticulture, Michign Stte University A8 Plnt nd Soil Sciences Building, Est Lnsing, Michign, USA 88 Asprgus replnt suppression is mjor thret to sprgus production worldwide. The problem is more pronounced in res with long trdition of sprgus production where virgin lnd is limited. Under those conditions erly decline nd stnd reduction re observed in newly replnted fields nd the life spn of those fields cn esily be reduced significntly. Fungicides nd soil fumignts re use to help reduce the impct of the problem. If proven effective, disese free plnting mterils like greenhouse-grown trnsplnts nd crop mngement prctices like soil mendments nd cover crops tht help improve soil qulity could be dded in the tool box for mngement this problem. Objectives - Extend sprgus field productivity through culturl prctices, nd soil mendments - Compre field performnce of greenhouse-grown trnsplnts to one-yer-old crowns - Evlute the potentil to integrted mustrd cover crops in sprgus production nd their impct on crop growth Methodology Effect of soil mendments cover crops plnting mterils nd cover crops Trils were estblished t the Asprgus Reserch Frm in Ocen County, MI in 7. The tril used minly trnsplnts but lso contined tretment with crowns for dditionl comprison. Millennium trnsplnts were strted in the greenhouse on April 13-15, 7, moved outside for hrdening off on June 1, 7, nd trnsplnted on June 1, 7. The tretments were: 1) Diry compost (see Tble 1 for rte/yer); ) SoilBuilder ( gl/cre fter TerrClen t gl/cre) Microbil soil mendment; 3) Mustrd Cover crops ( mixture of oilseed rdish t 5 lb/a nd Orientl mustrd t 3 lb/a) ) One-yer-old crown; 5) Control Compost nd SoilBuilder were pplied every yer (Tble 1). One-yer-old crowns Millennium (treted with cnnonbll) were plnted My 8. Therefore, both crowns nd trnsplnts in the study hve bout the sme ge. To void excessive competition with young trnsplnts the cover crop ws not plnted in 7 seson. In 8, the cover crop ws plnted on Aug 1, 8, August 5, 9, nd August 18, 1. The seed ws brodcst fter shllow tillge between rows nd incorported to bout ½ to 1 inch.

16 Tble 1. Tretments. Tretment Treted control Cnnonbll Untreted control TerrClen 1 Gl/A Drench 1 Gl/A Drench 1 Gl/A Drench 1 Gl/A Drench SoilBuilder Gl/A Drench Gl/A Drench Gl/A Drench Gl/A Drench Compost 1 tons/a (6-9-7) 5 tons/a (5-9-8) 3 tons/a (7-7-9) 3 tons/a (7-15-1) Rtings consisted of yield nd sper count (April 3-June 15 in 1), nd soil smpling (July 15 1). Fern dry weight fter fern deth in November 9 nd 1 ws lso recorded. Effect of soil mendments under fumigted nd unfumigted conditions Field studies were estblished in Ocen County, MI in 7 to ssess the efficcy of soil mendments/fumigtion on sprgus Millennium. Ech field ws setup using rndomized complete block design with replictions. Frm A (unfumigted soil nd untreted crowns): This site ws unfumigted nd untreted one-yer-old sprgus crowns Millennium were trnsplnted on 3 My 7. A single row ws used for ech plot. Rows were on 5-foot centers, with 1-inch between plnts inside the row. Field B (fumigted soil nd treted crowns): This site ws fumigted with metm sodium (Sectgon ). One-yer-old Millennium crowns treted with the fungicide Fludioxonil (Cnnonbll TM, Syngent) were plnted on 6 June 7. Double stggered rows were used t this site. Double rows were on 5-foot centers, with 7-inch spcing between plnts in ech individul row. Plnt popultions used by the two commercil frmers were different but representtive of the industry prctices. Consecutive tretment rows were seprted with gurd rows to void tretment contmintion. Plots were 5 feet long but the number of plnts per plot vried between sites (5 plnts for site A nd plnts for site B). Tretments re indicted in Tble : Tble. Tretments. Tretment Treted control Cnnonbll Untreted control Mustrd brn tons/a tons/a tons/a tons/a TerrClen 1 Gl/A Drench 1 Gl/A Drench 1 Gl/A Drench 1 Gl/A Drench SoilBuilder Gl/A Drench Gl/A Drench Gl/A Drench Gl/A Drench Compost 1 tons/a 5 tons/a 3 tons/a 3 tons/a Rtings consisted of stnd counts, hrvest yields (April 3-June 15 in 1), nd soil smpling (July 15 1). Results Effect of soil mendments cover crops plnting mterils nd cover crops In November 9 fter fern deth, one-yer-old crowns tretment hd the lowest fern dry weight followed by the cover crop tretments. Compost plot produced the highest fern biomss t the end of the growing seson.

17 In 1, one-yer-old crown hd the lowest yield nd sper count, nd compost the highest yield nd sper count. These results were in greement with fern biomss evlution in November 9. All trnsplnt tretments yielded more thn one-yer-old crowns tretment for both totl weight nd sper count. Tble 3. Asprgus yield nd sper count s ffected by the tretments Fern 9 Yield 1 Tretment Totl dry weight (g/plot) Weight (g/plot) Sper count (per plot) Diry compost Brssic cover crops 1.6 c b 11. b Microbil soil mendment.3 b b 13. b Control 1.9 bc 391. b 115. b One-yer-old crown.61 d c 73. c LSD P-Vlue.1 <.1.11 Effect of soil mendments under fumigted nd unfumigted conditions Field A (unfumigted site) showed significnt yield differences mong tretments. Upon finl sprgus hrvest on 1 June 1, yellow mustrd brn showed the highest yield. This ws followed by the tretment where crowns were treted with Cnnonbll prior to plnting in unfumigted soil. In Field B (fumigted site), none of the tretments ffected sprgus yield nd sper count. Tble. Yield nd Sper Count per plot in 1*. Field A Field B Weight Count Weight Count Compost b Mustrd SoilBuilder* b Treted Control b Untreted Control b TerrClen LSD P-Vlue Note tht plnting density ws different between fields SoilBuilder ws pplied bout 1 hour fter TerrClen in the tretment lbeled SoilBuilder. Acknowledgments Funding for this work ws provided in prt by Project GREEEN (Generting Reserch nd Extension to meet Economic nd Environmentl Needs) # GR7-8, USDA-NIFA PMAP Awrd # , Michign Asprgus Reserch Committee nd Michign Vegetble Council. We pprecite inkind nd technicl support from our grower coopertors (Tom Oomen, Rick Oomen, Ken Oomen nd Rlph Oomen).