Texas Panicum Control in Field Crops and Commercial Vegetables

Transcription

1 Weed Fcts WF-22 Texs Pnicum Control in Field Crops nd Commercil Vegetles Texs pnicum is considered to e one of the most troulesome weed species in the southestern US. Texs pnicum plnts will grow under rnge of soil moisture levels. Seeds re cple of emerging from soil depths of 3 inches. Also, Texs pnicum will continue to emerge throughout the summer. Texs pnicum is esily identifile from other summer nnul grsses ecuse of the short thick hirs tht develop on oth the upper nd lower lef surfce. Currently, no other grss species tht infests gronomic crops in Delwre hs short thick hirs on oth lef surfces. Pursunt to the provisions of Title 3, Chpter 24 of Delwre Code, s Amended 1995, the Delwre Deprtment of Agriculture under its Rules nd Regultions hs declred Texs pnicum noxious weed. Designtion s noxious weed requires tht Texs pnicum must e controlled. Drwing from Knss Stte University (Permission eing sought) Texs pnicum (Pnicum texnum Buckl.) sometimes referred to s Texs millet (Urochlo texn) is n extremely competitive summer nnul grss tht commonly reches heights of 2 to 3 feet nd forms dense ptches in fields nd rodsides. Texs pnicum reproduces only y seed. Individul plnts will root t nodes tht come in contct with the soil. A noxious weed is plnt tht hs dverse effects on or thretens griculturl production. A plnt is designted s noxious y the U.S. or Delwre Deprtments of Agriculture. An ttriute of noxious weed is tht it is difficult to control with mny stndrd weed control progrms. Often fields infested with noxious weed need specil ttention nd require different mngement thn non-infested fields. Growers who hve noxious weeds cn cll Todd Dvis, noxious weed specilist t Delwre Deprtment of Agriculture to sign WF-22 _ 1

2 complince greement. Filure to control this weed cn result in fines of $25 per cre ($100 minimum). Noxious weeds cn e reported to Mr. Dvis t He will contct the owner or gency to work on developing control progrm. Noxious weeds must e controlled on rights-of-wy, lots nd undeveloped lnds s well s frmlnd. PREVENTION Moving equipment cn spred Texs pnicum seed within field or from field to field. Proper clening of equipment requires use of n ir compressor, pressure hose, or sweeping. Letting the equipment run to clen itself out is not dequte. Be sure tht orgnic mterils such s strw, mulch, mnures, nd seeds re not infested with Texs pnicum or other weed seeds. Mke sure Texs pnicum plnts outside the field re controlled. MECHANICAL AND CULTURAL CONTROL Culturl prctices tht result in rpid, dense crop cnopy will improve overll level of control of Texs pnicum. Since Texs pnicum will emerge throughout the summer until erly fll, crop cnopy is very importnt to prevent emergence nd limit seed production of these lte emerging plnts. Post-hrvest control with mowing, tillge, or hericides is importnt to limit seed production. Texs pnicum plnts will recover fter erly hrvested corn or vegetles, nd without dditionl control mesures these plnts re cple of producing lrge numers of seed. Cultivtion Cultivtion in comintion with hericide ppliction cn increse the overll level of control. Do not cultivte 7 dys efore tretment or until 7 dys fter tretment. When cultivting, cre must e tken to void ringing soil not treted with n hericide ner the soil surfce, therey incresing the opportunity for seeds to germinte nd seedlings to emerge. CONTROL IN CORN Effective Texs pnicum control cn e chieved in field nd silge corn production. Texs pnicum control cn e expected in corn when spryed with products contining glyphoste 1 nd nicosulfuron hericides. These products re pplied postemergence. Preemergence Control Emerged Texs pnicum in no-till fields should e spryed with glyphoste prior to plnting. A preemergence ppliction of residul products such s s-metolchlor or pyroxsulfone my provide some suppression, ut postemergence hericides will lmost lwys e necessry for complete control. None of the soil-pplied hericides will provide seson-long control of Texs pnicum. Postemergence Control The following tle lists hericides tht cn e used t leled rtes nd ccording to lel directions to control emerged Texs pnicum plnts. See lels for detils. Alwys consult 1 Glyphoste is the ctive ingredient in ll Roundup nd Touchdown formultions. Glyphoste is lso ville under mny other nmes nd s prt of numerous prepckged mixtures. Rtes ssume glyphoste pckged s 4 l i (3 l e) gllon. WF-22 _ 2

3 hericide lels for the proper djuvnts to use. Consider whether tnk-mixes, split pplictions or follow-up pplictions tht re recommended on the lel would e preferred to using single product or timing. Other importnt considertions re crop vriety, soil insecticide interctions, environmentl conditions, crop helth nd stge, nd crop rottions. All of this informtion is ville on the hericide lel. Mny of the following hericides provide control of emerged Texs pnicum plnts, ut they will not provide residul control (glyphoste, Impct, Ludis, Lierty 280, etc). The ddition of rimsulfuron or pyroxsulfone contining hericides my provide residul control. Post-hrvest Mngement Mowings, diskings, or rodcst hericide pplictions fter hrvest will prevent seed production nd is very importnt for long-term mngement. Corn growth stge- TX pnicum mximum size or rnge Hericide mximum Efficcy Hericide Brodcst Directed group size Rte/A Rting Accent Q V6 or 20 in V10 or 36 in 2 3 in 0.9 oz G-E Cpreno V6 n/ in 3 oz F-G Glyphoste products c V8 or 30 in n/ 9 8 in 1 qt G-E Impct/Armezon up to 45 dys pre-hrvest s needed 27 3 in 1 oz F-G Ludis up to V8 n/ 27 3 in 3 oz F-G Lierty 280 d through V5 n/ 10 4 in 22 oz F-G Option V5 or 16 in 16 to 36 in 2 3 in 1.5 oz G Stedfst Q V6 or 20 in n/ in 0.75 oz G E = Excellent (>90% control) G-E = Good to Excellent G = Good (80-90% control) F-G = Fir to Good F = Fir (60-80% control) Accent Q, Option, Stedfst Q, nd other hericides contin restrictions concerning soil insecticide use. Follow lel restrictions crefully or serious crop injury my occur. c Glyphoste is the ctive ingredient in ll Roundup nd Touchdown formultions. Glyphoste is lso ville under mny other nmes nd s prt of numerous prepckged mixtures. The rte given in the tle is for glyphoste with formultion of 4 l i (3 l e) per gllon. Adjust the rte for other formultions. All glyphoste products require the use of glyphoste-resistnt corn hyrids. Using these products on corn hyrids tht re not glyphoste-resistnt will seriously injure or kill the crop. d Lierty 280 requires the use of glufosinte-resistnt corn hyrids. Using this product on corn hyrids tht re not glufosinte-resistnt will seriously injure or kill the corn crop. CONTROL IN SOYBEANS Texs pnicum control in soyens relies on postemergence options. Soil-pplied hericides such s Commnd my provide some suppression, ut not full-seson control. Postemergence Control There re severl highly effective postemergence hericides ville for control WF-22 _ 3

4 of Texs pnicum. The following hericides cn e used t leled rtes nd ccording to lel directions to control emerged plnts. Sequentil or follow-up pplictions my e needed for full-seson control. Assure II, Trg, Fusilde DX, Select, Select Mx, Post, Post Plus, nd Fusion re very sfe to soyens, ut do not provide ny rodlef weed control. If rodlef weeds re present, consult the grss hericide s lel for. the est procedures to follow. Tnk-mixing rodlef hericides with the postemergence grss hericides cn result in ntgonism (lck of control). Alwys consult hericide lels for the proper djuvnts to use. Other importnt considertions tht re ddressed on the hericide lel re crop vriety, environmentl conditions, crop helth nd stge, nd crop rottion. Efficcy Hericide Mximum Texs rting for Hericide Rte group pnicum size seedlings Fusilde DX 12 oz 1 8 in G Fusion 8 oz in G Glyphoste products 22 oz 9 12 in G Lierty oz 10 4 in F-G Post 16 oz 1 8 in G Post Plus 24 oz 1 8 in G Select 6-8 oz 1 6 in G Select Mx oz 1 6 in G Trg / Assure II 10 oz 1 4 in G E = Excellent (>90% control) G-E = Good to Excellent G = Good (80-90% control) F-G = Fir to Good F = Fir (60-80% control) P-F = Poor to Fir P = Poor (20-60% control) Glyphoste products require the use of glyphoste-resistnt soyen vrieties. The rte given in the tle is for glyphoste with formultion of 4 l i (3 l e) per gllon. Adjust the rte for other formultions. Using these products on soyen vrieties tht re not glyphoste resistnt will seriously injure or kill the soyen crop. CONTROL IN GRAIN SORGHUM There re no stisfctory rodcst tretments currently ville for controlling Texs pnicum in grin sorghum. Grin sorghum should not e plnted in fields where there is hevy Texs pnicum infesttion. CONTROL IN PASTURE AND FORAGE There re no stisfctory rodcst tretments currently ville for controlling Texs pnicum in permnent psture. Mowing my e n pproprite lterntive to chemicl control to prevent seed production. In lflf, Select (6 to 8 oz/a), Select Mx (12 to 32 oz/a), Post (1.5 pt/a), or Post Plus (2.25 pt/a) cn used for postemergence control of Texs pnicum. Alwys consult hericide lels for surfctnts to use, pproprite weed nd crop stges, grzing, feeding, hying, nd slughter intervls, nd other restrictions. WF-22 _ 4

5 CONTROL IN VEGETABLE CROPS Successful Texs pnicum control in vegetle crops cn e otined with timely mngement. It is importnt to recognize tht control strtegies will rely on timely postemergence sprys of Select, Select Mx, Post, or Assure II/Trg. Refer to the lels for those registered for use in your re. Ludis nd Impct (or Armezon) will provide postemergence control in sweet corn. Mowings, diskings, or rodcst hericide pplictions fter hrvest will prevent seed production nd is very importnt for long-term mngement. SPOT-SPRAY CONTROL (Crop nd Noncrop) Spot tretment cn e mde in corn, soyens, whet, rley, ots, sorghum, forge, psture, nd non-crop res. For smll or loclized res, use the chrt elow nd pply the recommended concentrtion on spry-to-wet sis (1 gl/1000 ft 2 ) to provide thorough coverge. For lrger res, refer to the hericide lel for rtes to pply on percre sis. Also, include surfctnts sed on mnufcturers recommendtions. Mowing my e n pproprite lterntive, ut repeted mowing mye need to prevent seed production. Amount of hericide to mix with vrious volumes of wter Gllons of wter Glyphoste Trg / Assure II Fusilde DX Post Post Plus Select Mx Crop oil conc. c qt 25 fl oz 30 fl oz 40 fl oz 60 fl oz 40 fl oz 1 gl fl oz 6 fl oz 7.5 fl oz 10 fl oz 15 fl oz 10 fl oz 1 qt oz (1.6 Tsp) 0.2 oz (1.4 tsp) 0.3 oz (1.8 tsp) 0.4 oz (2.4 tsp) 0.6 oz (3.6 tsp) 0.4 oz (2.4 tsp) 1⅓ oz (2½ Tsp) Spot pplictions re sed on sprying to wet leves ut not to the point of spry running off the leves (estimted t 40 gl/a of spry volume). Add surfctnt s required y the lel. Amount is sed on 4 l i (3 l e) formultion of glyphoste. c Add crop oil concentrte t 1% v/v to ll of the postemergence grss hericides. NOTE: Glyphoste will kill non-glyphoste resistnt crops nd the postemergence grss hericides will kill ny grss-like crops (corn, sorghum, psture grsses, etc.) in the treted re. Tke cre to void drift outside the trget re. These products do not provide residul weed control; therefore, Texs pnicum plnts tht hve not emerged t time of ppliction will not e controlled. Authors: WF-22-3/15 Mrk VnGessel Extension Specilist/Professor Weed Science nd Crop Mngement Deprtment of Plnt nd Soil Sciences University of Delwre Quintin Johnson Extension Associte IV Weed Science nd Crop Mngement Deprtment of Plnt nd Soil Science University of Delwre Coopertive Extension Eduction in Agriculture nd Home Economics, University of Delwre, Delwre Stte University nd the United Sttes Deprtment of Agriculture cooperting. Distriuted in furthernce of Acts of Congress of My 8 nd June 30, It is the policy of the Delwre Coopertive Extension System tht no person shll e sujected to discrimintion on the grounds of rce, color, sex, disility, ge, or ntionl origin. Commercil compnies or products re mentioned in this puliction solely for the purpose of providing specific informtion. Mention of compny or product does not constitute gurntee or wrrnty of products y the Agriculturl Experiment Sttion or Delwre Coopertive Extension or n endorsement over products of other compnies not mentioned. WF-22 _ 5