Q.630.7 I v6c no. 907 1984 cop. 5 UNIVERSITY OF ILLINOIS LIBRARY AT URBANA CHAMPAIGN. AGRICULTURE Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://www.archive.org/details/weedmanagementgu1984hope no, 901 i*!5 <*:^«* ^SK**" fB« ^tt*G cod- Weed Management Guide & 0^ V ■\\J^- V.® ^ 1984 FOR COMMERCIAL VEGETABLE GROWERS Restricied-use herbicides are identified with an asterisk(*). You must be certified as a pesticide applicator to use restricted-use pesticides. See your county Extension adviser in agriculture for information. Weed growth reduces the income of vegetable grow- ers in the United States by millions of dollars annually as a result of lower yields, poorer quality, and added labor in harvesting and processing. This guide should be used together with the grower's knowledge of soil types and the crop and weed history of the area to be treated. Whether to use herbicides or other means of weed control depends in part on the severity of past weed infestations. In some instances, mechanical control may be sufficient. If so, shave off weeds with a sharp hoe or cultivator while gently break- ing up the crust. Deep tillage causes severe injury to many shallow-rooted plants and helps place a fresh supply of weed seeds in position to germinate. Keeping equipment sharp and in good condition will help reduce injury to desirable plants. Hoe carefully around your plants, and hand pull weeds close to the plants. For warm season crops such as fresh market to- matoes, peppers, eggplant, okra, cucumbers, and melon, black polyethylene mulch will control annual weeds, conserve moisture, and increase the soil temperature in early spring. The higher temperature increases early season growth. Natural mulch materials may require considerable hand labor for application. Most organic materials are bulky and must be hauled to the place of use. This is a problem for large commercial plantings. Organic mulches tend to reduce soil temperature. Herbicide application may be needed in addition to mechanical control. Several herbicides may be sug- gested for some crops. These herbicides have shown good control with no injury to the vegetables under test conditions. Not all herbicides cleared for use on a species are necessarily listed. Where the choice of more than one herbicide is suggested, the decision rests with the grower and is based on his knowledge of past weed infestations, crop rotations, and material costs. Where one herbicide will not control the weeds present, a com- bination of herbicides may be suggested. When using a herbicide for the first time, it is advisable to use a small-scale trial. These suggestions for weed control in vegetables are based on research at the Illinois Agricultural Experi- ment Station, the U.S. Department of Agriculture, and other research institutions. The University of Illinois and its agents assume no responsibility for results from the use of herbicides, whether or not they were used in accordance with suggestions, recommendations, or direc- tions of the manufacturer or any governmental agency. Reading the label of the herbicide container is the most profitable time you spend in weed control. Use of the material and methods of application and use de- pend on registration of the herbicide by federal and state Environmental Protection Agencies (EPA). Do not use any herbicide unless the label states that it is cleared for the use on the crop to be treated. Herbicides are being classified for general use or re- stricted use by the U.S. Environmental Protection Agency. A person wishing to use a herbicide classified for restricted use must be certified as a private or com- mercial pesticide applicator by the Illinois Department of Agriculture. Contact your county Extension adviser in agriculture for details about this program. Only a few herbicides have been classified at this time. When applying mixtures of chemicals, the user as- sumes responsibility for freedom from residues if the mixture is not labeled by the EPA. Suggestions sometimes change during the growing season, based on EPA clearances that were made after this circular was issued. This publication, printed once a year, is subject to change without notification. Watch for notice of changes in the EPA registration of herbicides (as released by the EPA) in the Illinois Vegetable Farmer's Letter and the Insect, Weed, and Plant Disease Survey Bulletin. Subscription forms for the latter are available from the Agricultural Newsletter Service, 116 Mumford Hall, 1301 West Gregory Drive, Urbana, Illinois 61801, or your county Extension Office. You can obtain the Vegetable Farmer's Letter from Vegetable Crops Extension, University of Illinois, 1103 West Dorner Drive, Urbana, Illinois 61801. Some changes will be released through the Vegetable Growers "Hotline." UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN COLLEGE OF AGRICULTURE Prepared by H. J. Hopen, Department of Horticulture (revised annually) COOPERATIVE EXTENSION SERVICE CIRCULAR 907 (October 1983) For Application During the Growing Season (1984 Only) Crop Active ingredient per acre Weeds Treatment actually covered" controlled Timing of application (based on crop stage) Remarks, cautions, limitations Asparagus (seedlings) Amiben 3 1b. Annuals Immediately after seeding Irrigation or rainfall after treatment will give maximum control. Asparagus dalapon (established plantings) "'* diuron Princep Sinbar 5-10 lb. 1-4 lb. Perennial grass Annuals metribuzin 3-4 lb. Annuals 12-2.4 lb. Annuals 1-2 lb. Primarily broad- leaf weeds End of harvest season following disking In spring, after harvest, or both In spring, after harvest, or both In spring, after harvest, or both Early spring before the spears emerge or after harvest Apply when grass weeds are 3 to 4 in. tall. Direct spray under fern growth. Use surfactant as directed on label. Apply after disking. Do not exceed 6 lb. per growing season ; use a lighter rate on sandy soil. With diuron and Princep, a spring application may be sufficient after the first year. Apply after disking. Do not treat during the last year in asparagus because of residue. Use lower rates on coarse soils. Do not apply more than 2.4 lb. per acre per year. Do not use on sods with less than 1 percent organic matter. Do not plant to any other crop for two years after application. Apply after disking. Do not apply within 14 days of har- vest Can help control broadleaf weeds when used with dalapon, diuron, or Princep. Do not apply more than 2 lb./acre per growing season. Preemergence Beans, dry, Treflan 0.5-0.75 lb. lima and snap d Basalin 0.75-li lb. dinoseb 6-7.5 lb. Postemergence Annuals" Preplant soil application, in- (primarily grasses) corporate with soil immediately Annuals Preplant soil application, incor- (primarily grasses) porate with soil immediately Annuals Can be used between planting and crop emergence Basagran 0.75-1 lb. Annual broad- leaf weeds, Canada thistle, nutsedge When weeds are small and are actively growing; after the first trifoliate leaf appears on beans Plant crop immediately, or within 3 weeks after applica- tion. Can use up to 1 lb. per acre on dry beans. Do not use on light, sandy soil. Some stand reduction may result from use. See label for precautions. Can provide good, broad-spectrum control when combined with a grass-active herbicide. Do not mix with other pes- ticides. See Basagran entry under corn, postemergence for Canada thistle and nutsedge control. Beans, snap EPTC 3 lb. EPTC 2-3 lb. + Treflan 0.5-0.75 lb. Dacthal 6-10 lb. Annual grasses and nutgrass' Preplant soil application, incor- porate with soil immediately Preplant soil application, incor- porate with soil immediately Annuals* Immediately after seeding (primarily grasses) Research results have shown this combination to control a broader spectrum of weeds than either herbicide alone. Do not feed treated plant parts to livestock. Beans, lima Amiben and dry Dual Lasso 2-3 lb. 1.5-3 lb 2-3 lb. Broad spectrum of annual weeds Annuals Annuals Immediately after seeding, or preplant-incorporated for lima beans Preplant soil application, incor- porate with soil, or pre- emergence Lima beans : preplant soil ap- plication, incorporate into upper 1 to 2 inches, or pre- emergence. Dry beans: pre- plant soil application, incor- porate into upper 1 to 2 inches, or preemergence Field may be rotary-hoed without destroying herbicide action. Beans, dry EPTC + Treflan 2-3 lb. 0.5-0.75 lb. Preplant soil application, incor- porate with soil immediately Research results have shown this combination to control a broader spectrum of weeds than either herbicide alone. Beets, garden 4 Pyramin Ro-Neet 4 1b. 4 1b. Annuals (primarily broadleaved) Annual grasses Preemergence or after beets emerge and before weeds have two true leaves Preplant soil application, incor- porate with soil immediately Rainfall or irrigation needed to activate. Where grasses are a severe problem, use 4 lb. of Pyramin plus 4 lb. of Ro-Neet. Use a combination treatment with Pyramin to broaden control spectrum. Direct-seeded or transplanted Broccoli* Treflan 0.5-0.75 lb. Annuals* Brussels (primarily grasses) sprouts 4 Cabbage" Dacthal 6-10 lb. Annuals" Cauliflower 4 (primarily grasses) Preplant soil application, incor- porate with soil immediately Immediately after seeding. Can also be incorporated preplant Stunting or growth reduction may occur at recom- mended rates under growth stress conditions. Can use up to 1 lb. per acre on transplants. Carrots 4 Preemergence Treflan 0.5-1 lb. Annuals* (primarily grasses) Carrot* continued on tkt n+xt p*ff*. Preplant soil application, incorporate with soil immedi- ately Seed after application to 3 weeks later. All notes are at the end of this table (page 6). r\GX For Application During the Growing Season (continued) Crop Active ingredient per acre Weeds Treatment actually covered* controlled Timing of application (based on crop stage) Remarks, cautions, limitations Postemergence Carrots linuron 075-1.5 lb. (continued) 4 Annuals Stoddard Solvent 60-80 gal. Annuals Postemergence on carrots only after the crop is 3 in. tall ; grasses, less than 2 in. ; broad- leaves, less than 6 in. After two true leaves have appeared (do not apply to carrots or parsnips after they are >4 in. in diameter, since an oily taste may result) Do not feed treated foliage to livestock or replant treated area for 4 months. More than one application may be made, but do not exceed a total of 2 lb. per acre. Do not use over 40 PSI. Use no surfactants when tempera- tures exceed 80° F., or crop injury may result. Most effective when sprayed on cloudy days or during high humidity, and when weeds are not more than 2 inches high. May not control ragweed. Do not apply within 40 days of harvest. Can be used on celery, dill, parsnips, and parsley. Preemergence Corn, pop 4 atrazine 2-3 lb. (See sweet corn) (See sweet corn) Bladex Dual (See remarks) 1.5-3 lb. Annuals Annuals Preemergence only Eradicane, 4-6 lb. Eradicane Extra Lasso 2-4 lb. Princep 2-4 lb. Preplant soil application, incorporate with soil, or preemergence Difficult-to-control Preplant soil application, weeds incorporate with soil Annuals Preemergence Annuals Preemergence Sutan+ 3-4 lb. Postemergence 2,4-D 0.5 lb. Basagran 0.75-1 lb. Primarily annual grasses Broadleaved weeds Broadleaved an- nual weeds, Canada thistle, and nutsedge Preplant soil application, incorporate with soil Postemergence (See sweet corn) See sweet corn, except the section on preemergence com' binations. Some pop corn varieties are sensitive to the application rate. (See remarks on Bladex under sweet corn.) See sweet corn. See sweet corn. Plant only crops so specified on the label the following year. Do not graze treated areas. See sweet corn. Apply when corn is 3 to 10 in. tall. (See sweet corn) Corn, sweet e,< Preemergence atrazine 2-3 lb. Annuals, annual and perennial grasses" Bladex (See remarks) Annuals Preemergence, apply no later than 3 weeks after seeding. Shallow cultivation may im- prove weed control during dry weather. Preemergence only Dual 1.5-3 lb. Annuals Eradicane, 4-6 lb. Eradicane Extra 4 lb. Preplant soil application, incorporate with soil, or preemergence Difficult-to-control Preplant soil application, weeds incorporate with soil Lasso propachlor 2-4 lb. 4-6 lb. Annuals Annuals Preemergence Preemergence butylate + 3-4 lb. Primarily Preplant soil application, annual grasses incorporate with soil Combinations Dual, Eradicane, Eradicane Extra, Lasso, propachlor, and Sutan-f may be the spectrum of weed control and reduce residue and carryover. See labels of Postemergence 2,4-D 0.5 lb. (amine) atrazine 2 lb. Broadleaved weeds Annuals, annual and perennial grasses' 1 Postemergence Directed spray 3 weeks after emergence Corn continued on the next page. Grow corn a second year without atrazine treatment This chemical has a high soil residue. Do not plant other vege- table crops on a sprayed area until a second year of corn has been grown. Use atrazine where quackgrass is a prob- lem. Residue hazard decreased when banded or in com- bination with Lasso, propachlor, or Sutan. Some sweet corn varieties are sensitive to the application rate. Has been shown to have less soil residue than atra- zine. See label for rates and precautions. Do not use post- emergence, or on sandy or loamy-sandy soils (under 1 percent organic matter). Can be combined with other herbicides to reduce the rate being used. NOTE: The Shell Chemical Co. has a bulletin on using Bladex on pop and sweet corn. Use to control weeds that are difficult to control with other herbicides, such as wild cane, nutsedge, quackgrass, wild Proso millet, and seedling Johnsongrass. Eradicane Extra contains an "extender" which may lengthen the period of control in fields where Eradicane control has been shortened after several years of continuous use. Preplant incorporation may aid control of nutgrass. Do not use on sandy soils. Is an excellent herbicide on soils with a high organic-matter content Especially useful on sandy soil and where nutgrass is a problem. combined with atrazine or Bladex or Basagran to broaden herbicides for rates and application methods. Preferably, apply before corn is 6 in. tall. If corn is over 12 in., reduce the rate to \i lb. Can be combined with crop oils for postemergence appli- cation as emergency measure. This may increase residue the following year; preemergence use preferred. Do not graze or feed treated foliage for 21 days after treatment All notes are at the end of this table (page 6). For Application During the Growing Season (continued) Crop Active ingredient per acre Weeds Treatment actually covered* controlled Timing of application (based on crop stage) Remarks, cautions, limitations Corn, sweet (continued)''* 1 Basagran 0.75-1 lb. Broadleaved an- nual weeds, Canada thistle, and nutsedge Early postemergence when the weeds are small and actively growing. Delay will result in less control. For Canada thistle and nutsedge, split applications are preferred. Make the first one when the plants are 6 to 8 in. tall; for nutsedge, 7 to 10 days later; for Canada thistle, 10 to 14 days later (or use one application plus cultivation). Do not mix with other pesticides. Cucumbers Alanap L Muskmelons' Watermelons' Prefar Prefar plus Alanap L 3-5 lb. 3-3.5 lb. 4-6 lb. 4 1b. +2-3 lb. Annuals' Immediately after seeding or transplanting After transplanting or vining Annuals Preplant soil application, (primarily grasses) incorporate with soil immediately Grasses and broadleaved Preplant light incorporation Do not use on cold soil. Rainfall or irrigation after treat- ment gives maximum control. Keep away from foliage. Apply to soil after the weeds have been removed. Is primarily a grasskiller. Consult label for sensitive crops within 18 months after application. Can be used in rotation with tomatoes, broccoli, cauliflower, lettuce, carrots, onions, and summer squash within 18 months. Soybeans can be planted 12 months after application. Has value for broad-spectrum weed control. Consult label for sensitive crops within 18 months after Prefar applica- tion. Has EPA approval as a tank mixture. weeds Where earliness is desired, black polyethylene mulch can be used as an alternative to herbicides. It will control annual weeds, conserve moisture, and increase the soil temperature in early spring. Eggplant Dacthal 6-10 lb. Annuals* After plants are established, (primarily grasses) 4-6 weeks after transplanting Cultivate and weed prior to application. Can be applied to plants as part of a uniform soil application. Greens (for beets, mustard greens, and spinach — see note d) Devrinol 1-2 lb. Annuals Preplant soil incorporation For use in transplanted eggplant. Where earliness is desired, black polyethylene mulch can be used as an alternative to herbicides. It will control annual weeds, conserve moisture, and increase the soil temperature in early spring. Dacthal 6-10 lb. Annuals' Immediately after seeding For use on collards, kale, mustard greens, and turnips. (primarily grasses) Treflan 0.5-0.75 lb. Annuals' Preplant soil application, in- For use on collards, kale, mustard greens, and turnip (primarily grasses) corporate with soil immediately greens. Furloe 1-2 lb. Primarily broad- Preemergence For spinach only. Use lower rates in cool, wet weather. leaved annuals Horseradish* Dacthal 6-10 lb. Annuals* Immediately after (primarily grasses) transplanting Lettuce* Balan Kerb* 1.5 lb. 1-2 lb. Annuals Annuals Preplant soil incorporation Incorporate with soil immediately Preemergence or preplant- incorpo rated Is primarily a grasskiller. Seed after application to 3 weeks later. Do not plant wheat, barley, rye, grass, onions, oats, beets, or spinach for 12 months after application. Do not use when the air temperature exceeds 85° F. Use the lower rates listed on sandy soil. Do not use on peat or muck soils. See label for rotation crops. For best results, rainfall or irrigation is needed 1 to 2 days after applica- tion, especially during warm weather. Okra" Dual 1.5-3 lb. Annuals Enide Treflan 3-5 lb. 0.5-1 lb. Onions* Preplant soil application, incorporate with soil, or preemergence Annuals At planting Annuals Preplant soil application, (primarily grasses) incorporate with soil immediately Where earliness is desired, black polyethylene mulch can be used as an alternative to herbicides. It will control annual weeds, conserve mois ture, and increase the soil temperature in early spring. Preemergence Dacthal 6-10 lb. Randox 4-6 lb. Postemergence Furloe Brominal 3-6 lb. Annuals* Immediately after seeding (primarily grasses) or transplanting Annuals' Just before onions emerge (primarily grasses) Broadleaved On seeded onions : weeds (especially loop stage or after 3- to smartweed) 4-leaf stage 0.25-0.38 lb. Broadleaved weeds When onions have 2 to 5 true leaves May not kill smartweed or common ragweed Can be used on seeds, sets, or seedlings. Use only on mineral soils. Use lower rates on sandy soils. A double application of Dacthal can be used at seeding, layby, or both. Use on muck soils. Heavy rainfall may reduce stand. Very effective on purslane and pigweed In later sprays, direct at base of onion plant. If applied more than once, do not exceed 6 lb. per acre for the season. Use lower rates in cool, wet weather. Use no later than 30 days before harvest Do not use on sandy soils. Use 50 to 70 gallons of water per acre. Apply when onion foliage is dry for greatest crop safety. Suggested temperature for spraying is 80° F with low humidity. All notes are at the end of this table (page 6). For Application During the Growing Season (continued) Crop Active ingredient per acre Weeds Treatment actually covered' controlled Timing of application (based on crop stage) Remarks, cautions, limitations Preemergence propachlor Treflan 4-5 lb. 0.5-0.75 lb. Annuals Annuals Trcflan + Surflan 0.5 lb. + 0.5 lb. Annuals Basalin 0.5-0.75 lb. Annuals Dual 1.5-3 lb. Preemergence or Postemergence dinoseb 0.3-9 lb. Annuals (primarily broad- leaved weeds) Preemergence Preplant soil incorporation, incorporate with soil immediately Preplant soil application, incorporate with soil immediately Preplant soil application, (primarily grasses) incorporate with soil immediately Annuals Preplant soil application, incorporate with soil, or preemergence Do not use on sandy soil. Seed after application to 3 weeks later. Some reduction of growth and stand reduction possible under stress. May suppress some root rot. Do not use on soils of less than 1.5 percent organic matter. May suppress Aphanomyces root rot. May broaden weed control more than either herbicide alone. Do not feed forage to livestock. Do not plant any root crop for 12 months after application. Postemergence Basagran 0.75-1 lb. MCPB lib. 0.25-0.5 lb. MCPA (Na salt) Vacate 0.115-0.154 (MCPA amine) lb. Annual broad- leaved weeds, Canada thistle, nutsedge Broadleaved .weeds and Canada thistle Preemergence or postemergence When weeds are small and are actively growing; after peas have 3 pairs of leaves (or 4 nodes) When peas are 3-7 in. tall and no later than 4 nodes prior to pea blossom Preemergence, use 6 to 9 lb.; postemergence, use 0.3 to 1.1 lb. Apply prior to bloom when peas are 2 to 8 in. tall. See label for further precautions. Preemergence use may help suppress root rot. Can help control Canada thistle. Can provide good, broad- spectrum control when used with a grass-active herbicide. Do not mix with other pesticides. See Basagran entry under corn, postemergence for Canada thistle and nut- grass control. Do not use crop oil. May delay maturity 1 to 4 days. Use at least 20 gallons of water per acre. Do not feed vines to livestock. MCPA is more effective on mustard. MCPB or Vacate may be less injurious to peas. Dual EPTC Treflan linuron dalapoo metribuzin Lasso Prowl 1.5-3 lb. 3-6 lb. 0.5-1 lb. 0.75-2 lb. 7 lb. 0.25-0.5 lb. £5-3 lb. 0.75-1.5 lb. Annuals Annual grasses and nutgrass' Annuals' Drag-off treatment at emergence Drag-off treatment at emer- gence or preplant soil application ; incorporate with soil immediately Drag-off treatment at (primarily grasses) emergence Annuals Apply prior to potato emergence Quackgrass Before plowing in spring; wait 4 days before plowing and planting Annuals Postemergence, following a (primarily preemergence grass broadleaved) herbicide Annuals Apply at drag-off Annuals Drag-off treatment at emergence Use lower rate on sandy soil. Use a light incorporation. Plant tubers at least 2 in. deep. Do not replant treated area to other crops for 4 months after treatment. May injure crop on light, sandy soil. Do not apply over exposed tubers. Not for fields intended for red-skinned varieties or White Rose. Do not plant potatoes for 4 weeks. Use surfactant as directed on label. Can be used preemergence also. Do not exceed 1 lb. per acre in a season. Do not apply within 60 days of harvest. Do not use on red-skinned or early-maturing white varieties. Do not apply in cool, wet weather. Do not use on sandy soils. Can be used alone or in com- bination with Lorox, dinoseb, Lexone, or Sencor. Use a light incorporation within 7 days. May be com- bined with Sencor/Lexone, EPTC, or linuron. Dacthal 6-10 lb. Annuals' Immediately after planting (primarily grasses) Amiben 3 lb. Annuals Immediately after planting Enide 4-6 lb. Annuals Immediately after trans- planting Do not plant nonapproved crops on treated soil during the same season. Amiben Prefar 3-4 lb. 4-6 lb. Annuals As soon after seeding as possible, or preplant- lncorporated Annuals Preplant soil application, (primarily grasses) incorporate with soil immediately Use on loam soils. Amiben can be applied broadcast or banded over the row in pumpkins. Use on sandy soils. Is primarily a grasskiller. Consult label for sensitive crops within 18 months after applica- tion. Can be used in rotation only with tomatoes, broccoli, cauliflower, lettuce, carrots, onions, and summer squash within 18 months of application. Soybeans can be planted 12 months after application. All notej are at the end of this table (page 6). For Application During the Growing Season (continued) Crop Active ingredient per acre Weeds Treatment actually covered* controlled Timing of application (based on crop stage) Remarks, cautions, limitations Pumpkins propachlor Rhubarb 6 4-5 lb. Annuals Preemergence Do not use on sandy soils. paraquat* (See following table) Tomatoes, direct-seeded and trans- planted* Enide Devrinol Amiben metribuzin 4-6 lb. 1-2 lb. 3-4 lb. Annuals Annuals Annuals 0.25-1 lb. Primarily broad- (min.-max.) leaf. Should be used with a grass- active herbicide. 0.25-0.5 lb. 0.25-0.5 lb. 0.5-1 lb. (For min.- max. rates) Preemergence Preplant soil incorporated Tomato plants must have 5-6 true leaves Preplant incorporated. Post- emergence, can be broadcast or directed Preplant incorporated, trans- plant tomatoes Broadcast spray, established tomatoes Directed spray, established tomatoes Do not plant other food crops on treated areas for 6 months. If used under dry soil conditions, a shallow (1 in.) incorporation as a preplant treatment may improve weed control. Can also be used on transplanted peppers. Also used on direct-seeded and transplanted peppers. Enide + Devrinol is labeled as a tank mixture. Use granular formulation only. Apply to dry foliage to avoid leaf burn. Do not use on sandy soils. Apply with ground equipment to seeded and transplantec tomatoes. Do not use air-blast or other high-pressure spray equipment. Do not use on peppers. Alone or in a tank-mix combination with Treflan. Single or multiple applications. Minimum of 14 days be- tween treatments. Direct-seeded plants should have 5 ot 6 leaves; transplants should show new growth. Recommended for use in fields with severe weed prob- lems, or for fields with hard-to-control weeds. Do not apply within 7 days of harvest, or within 3 days following cool, wet, or cloudy weather; otherwise, crof injury may occur. Do not apply to established tomatoes within 24 hours after application of other pesticides. Dc not apply more than 1 lb./acre per crop season, or more than 1 lb./acre within a 35-day period. Allow at least U { days between applications, regardless of the dosage oi method used. Do not use hot caps on tomatoes within days before application, or at any time afterward. Do noi tank-mix with other pesticides, except Treflan. Tomatoes and Peppers, transplanted Amiben Treflan 3-4 lb. 0.5-1 lb. Annuals Wait 3 days after transplanting to apply Annuals" Preplant soil application, (primarily grasses) incorporate with soil immediately Use granular formulation only. Apply to dry foliage it; order to avoid leaf burn. Do not use on sandy soils. Some reduction of growth may be possible under growtl stress conditions, or if rates are higher than suggestec for the soil type. Where earliness is desired, black polyethylene mulch can be used as an alternative to herbicides. It will control annual weeds, conserve moisture, and increase the soil temperature in early spring. * Restricted-use herbicide. » Based on active ingredients (actual amount of active herbicide in material or acid equivalent). Use lower rate on sandy soil and higher rate on clay and loam soils. Whet using a band application over the row, adjust amount of material applied to the part of an acre treated. b For perennial weed control, applications during and outside the growing season, see the following table. c For stale seedbeds, before crop emergence, see the following table. «* For perennial grass control, applications outside the growing season, see thi following table. * May not control ragweed and panicutn. * May not control smartweed. « May not control ragweed, smartweed, and velvetleaf. h May not control crabgrass ■ May not control smartweed and velvetleaf. For Application Outside the Growing Season Stale seedbed, before crop emergence Asparagus paraquat* 0.5-1 lb. All emerged green foliage Before crop emergence; allow maximum weed emer- gence prior to treatment Weeds that emerge after treatment will not be controlled Crop plants that have emerged at application will be in jured. Do not apply within 18 months of harvest. Us< with a preemergence or preplant sustained-action weet control system. Rhubarb paraquat* 0.5-1 lb. All emerged green foliage Before crop emergence; allow Weeds that emerge after treatment will not be controlled maximum weed emergence prior to treatment but apply before dormant rhubarb buds in crown begin to grow. Corn, sweet paraquat* Lettuce Melons Peppers Potatoes Tomatoes 0.5-1 lb. All emerged green foliage Before crop emergence Weeds that emerge after treatment will not be controlled Crop plants that have emerged at application will be in jured. Use with a preemergence or preplant, sustained I action weed control system. * Restricted-use herbicide. For Application Outside the Growing Season (continued) Crop Treatment Active ingredient per acre actually covered* Weeds Timing of application controlled (based on crop stage) Remarks, cautions, limitations Perennial weed control, applications during and outside the growing season .sparagus Roundup 2-5 lb. (See remarks) Before emergence, or with shielded or directed sprays during fern growth Perennial grass control, applications outside the growing season sparagus Roundup eans, edible eet greens eets, red roccoli abbage auliflower om, sweet and pop orseradish, as a weed and as a crop irusalem artichoke 2-3 lb. (See remarks) (See remarks) Kale Lentils Lettuce Mustard greens Okra Onions Peas Potato, Irish and sweet Radishes Spinach Use to control milkweed, thistle, field bindweed, quack- grass, or Johnsongrass. Apply to quackgrass when it is 6-8 in. tall in the fall or spring. Apply to Johnsongrass when it is at least 12 in. tall and actively growing. Do not till for the specified time for each species (see label). Does not provide residual weed control. Do not mix, store, or apply Roundup spray solutions in containers or spray tanks made of galvanized or unlined steel (except stainless steel). Use for quackgrass or Johnsongrass control. Apply to quackgrass when 6 to 8 in. tall in fall or spring. Apply to Johnsongrass when at least 12 in. tall and actively grow- ing. Do not till until 3 to 7 days after application. Does not provide residual weed control. Do not mix, store, or apply Roundup spray solutions in galvanized steel or un- lined steel containers (except stainless steel). For control of volunteer horseradish, apply 3 to 4 lb. in mid-September. Field should have been disced 4 to 6 weeks prior to application. For this control practice, use spray coverage only. 'ote: In the suggestions in this publication, trade names of herbicides are usually used. The list below shows trade names and their >rresponding common names. Restricted-use herbicides are identified with an asterisk (*). ommon name Trade name Common name lachlor Lasso frazine AAtrex and Atrazine hnefin Balan wisulide Prefar v'ntazon Basagran lomoxynil Brominal litylate + safener Genate+, Sutan + DA A Randox Uoramben Amiben lorpropham Furloe anazine Bladex I cloate Ro-Neet lapon Dowpon CPA Dacthal Trade name Common name dinoseb Premerge-3, Sinox, Dinoseb diphenamid Enide diuron Karmex and others EPTC Eptam, Genep EPTC+safener Eradicane EPTC + safener + extender Eradicane Extra fluchloralin Basalin glyphosate Roundup, Kleen Up linuron Lorox, Linex MCPA, MCPB Vacate, numerous metolachlor Dual metribuzin Lexone, Sencor Trade name napropamide Devrino! naptalam Alanap L paraquat* Paraquat,* Gramoxone* pendimethalin Prowl pronamide* Kerb* propachlor Ramrod, Propachlor pyrazon Pyramin oryzalin Surflan simazine Princep terbacil Sinbar trifluralin Treflan Petroleum solvent Stoddard Solvent 2,4-D (amine) (numerous) Storing Pesticides and Containers Keep pesticides and containers in a separate building, room, or enclosure used only for this purpose. Such build- ing or rooms should be dry, ventilated, and locked. Fence outside storage areas to protect children and animals and to discourage pilferage. CAUTION: Do not store weedkillers, herbicides, or defoliants in the same room with in- secticides. Chlorate salts can create a fire or explosion hazard. Remove only the pesticides needed for one day's op- eration and return empty containers — and any unused pesticide — to the storage area each day. Disposing of Pesticides and Containers Surplus pesticides. To dispose of surplus pesticide mixtures, try to find other areas with the same pest problem and use up any extra tank mix or rinse water on these areas. Do not drain surplus pesticides in any loca- tion where they can contaminate wells, streams, rivers, lakes, or ponds. Operators of landfills meeting environmental safety standards can obtain supplemental permits to handle toxic waste materials, including pesticides. To dispose of large quantities of surplus pesticides, contact the Illinois EPA Division of Land Pollution Control to locate the nearest landfill with a supplemental permit for toxic waste or to obtain specific instructions about disposal. Pesticide containers. All empty pesticide containers, regardless of their type, should be rinsed three times before disposal. Rinse water should be dumped in the tank. Triple-rinsed containers should be punctured or broken to facilitate drainage and to prevent reuse for any purpose. They should then be hauled to a sanitary landfill for dis- posal. Small quantities of containers may be buried singly in open fields, with due regard for the protection of sur- face and subsurface water. Illinois regulations permit the burning of combustible containers provided that they are burned on the premises where they were used, that they are burned more than 1,000 feet from residential areas, that the burning will not cause undue visibility or environmental hazards, and that no reasonable alternative disposal method is available. Do not breathe smoke from burning pesticide containers, and do not burn containers that have weedkillers such as 2,4-D or similar herbicides. When these change to a gas, the vapors may damage nearby crops and shrubbery. Pesticides containing chlorates may explode when heated and therefore should not be burned. Growers with Several Crops in a Small Area Growers with several crops in a small area should be especially careful when applying herbicides. The tendency is to apply more if the quantity measured out "looks" as if it is not enough. A low-percentage granular formulation is suggested for small areas. Check rates and application techniques on the container label very carefully. Applica- tions must be accurate and uniform. Excessive amounts may cause injury to present or subsequent crops. Ideally, a specific herbicide should be fitted to a specific crop species. When growing several different crops in a small area, however, it is often impractical and expensive to use all the appropriate herbicides. Following are two herbicides that can be used on a wide range of vegetables. Dacthal. Dacthal is cleared on a large number of vegetables. As listed in this circular, it may not always be the herbicide of preference. It can be used on broccoli, brussels sprouts, cauliflower, cabbage, snap beans, mung beans, Southern peas, soybeans, seeded melons, cucumbers, squash, collards, kale, mustard greens, turnips (root and greens), garlic, horseradish, onions, potatoes (Irish), sweet potatoes and yams, tomatoes, eggplant, peppers, and strawberries. Do not use on beets or Swiss chard. Dacthal is a preemergence herbicide that must be applied to weed-free soil. It controls very small weed seed- lings soon after the weed seeds germinate. It is most effective if rainfall occurs or if the soil is irrigated within 2 to 3 days after application. A one-time application to all species is not always possible because some plants are susceptible to injury in early-growth stages. It is preferable to use Dacthal at seeding or transplanting time if the species is adapted to it. When this is not possible, the weeds should be removed and Dacthal applied to prevent further weed development. Consult the label for the appropriate application time. Dacthal is effective in controlling annual grasses that are a problem in the spring. Broadleaf weeds that escape control should be mechanically removed. Treflan. Treflan is widely available because it is used in soybean culture in Illinois. It can be purchased as a liquid with 4 pounds of active ingredient per gallon for large garden areas or as a low-percentage granular formulation for smaller areas. The amount of Treflan to use correlates very closely with the type of soil. The ap- propriate amounts are shown on the container label. Treflan can be used for weed control in beans (green, lima, and dry), broccoli, brussels sprouts, cabbage, cauliflower, carrots, kale, mustard greens, okra, peas, peppers, tomatoes, and turnip greens. Treflan may injure sweet corn. Treflan must be mixed with or watered into the soil to prevent loss of the chemical from the soil surface. A rototiller, disc, or similar implement should be used to mix Treflan with the soil to a 3- to 4-inch depth. When it is impractical to mix Treflan with the soil mechanically, remove all germinated and growing weeds and allow the herbicide to be carried into the soil through rainfall or sprinkle irrigation. Treflan is quite effective on annual grasses, but many broadleaf weeds will need to be mechanically removed. Mulches — see paragraph 3, page 1 Other Publications on Weed Control Copies of the following publications on weed control are available from the office of your county Extension adviser in agricul- ture and the Office of Agricultural Publications, 47 Mumford Hall, 1301 West Gregory Drive, Urbana, Illinois 61801. Calibrating and Adjusting Granular Row Applicators — Circular 1008 Controlling Weeds in the Home Garden — Circular 1051 Equipment and Calibration: Low Pressure Sprayers — Circular 1192 Turfgrass Pest Control — Circular 1076 Herbicides for Commercial Fruit Crops in Illinois — H-659* Herbicide Recommendations for Commercial Nurserymen — NC-2-80* 1984 Row Crop Weed Control Guide Weed Control in Small Grains, Forages, and Pastures * Available in Department of Horticulture, 125 Mumford Hall. Issued in furtherance of Cooperative Extension Work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, WILLIAM R. OSCHWAlt Director, Cooperative Extension Service, University of Illinois at Urbana-Champaign. The Illinois Cooperative Extension Service provides equal opportunities In program and employment. jm — 10-83 — 57641 — i UMWERSITYOHUINO.S-URBMIA C 907 REV. 198* C005