A 1.77 •' 
 
 / 
 
 Weed Control in 
 Lawns and Other Turf 
 
 4 
 
 m 
 
 United States 
 ^51 Department of 
 
 Agriculture 
 
 PREPARED BY 
 
 Agricultural 
 
 Research 
 
 Service and 
 
 Extension 
 
 Service 
 
 Home and 
 Garden Bulletin 
 Number 239 
 
Common, Chemical Names of Herbicides and Some Trademark 
 Names 
 
 Common Name Chemical Name 
 
 amitrole 3-amino-s-triazole 
 
 asulam 
 atrazine 
 
 benefin 
 
 bensulide 
 
 bentazon 
 
 bromoxynil 
 
 2,4-D 
 
 dalapon 
 
 DCPA 
 
 dicamba 
 
 dichlorprop 
 (2,4-DP) 
 
 DSMA, MSMA, 
 MAMA, CMA 
 
 glyphosate 
 
 mecoprop 
 (MCPP) 
 
 metham 
 
 methyl bromide 
 
 oxadiazon 
 
 pronamide 
 siduron 
 
 methyl sulfanilylcarbamate 
 
 2-chloro-4-(ethylamino)-6-(isopropyl- 
 amino)-s-triazine 
 
 N-butyl-/V-ethyl-a.a,a-trifluoro-2-6- 
 dinitro-p-toluidine 
 
 0,0-diisopropyl phosphorodithioate 
 S-ester with N-(2-mercaptoethyl) 
 benzenesulfonamide 
 
 3-isopropyl-1 H-2,1 ,3-benzothiadizain- 
 4(3H)-one 2,2-dioxide 
 
 3,5-dibromo-4-hydroxybenzonitrile 
 
 {2,4-dichlorophenoxy)acetic acid 
 
 2,2-dichloropropionic acid 
 
 dimethyl tetrachloroterephthalate 
 
 3,6-dichloro-o-anisic acid 
 
 2- (2,4-dichlorophenoxy) propionic 
 acid 
 
 methanearsonates 
 
 N-(phosphonomethyl)glycine 
 
 2-((4-chloro-o-tolyl)oxy]propionic 
 acid 
 
 sodium methyldithiocarbamate 
 
 bromomethane 
 
 2-tert-butyl-4-(2,4-dichloro-5- 
 isopropoxyphenyi)-AM,3,4- 
 oxadiazolin-5-one 
 
 3,5-dichloro-N-(1,1-dimetyl-2- KERB 
 
 propynyl) benzamide 
 
 1-(2-methylcyclohexyl)-3-phenylurea TUPERSAN 
 
 Trademark name(s)^ 
 
 AMINO TRIAZOLE WEED 
 KILLER, AMITROL-T, 
 CYTROL, WEEDAZOL 
 
 ASULOX 
 
 AATREX G 
 
 BALAN 
 
 BETSAN, PRESAN, 
 LESCOSAN, BETAMEC 
 
 BASAGRAN 
 
 BROMINAL, BUCTRIL 
 
 Too numerous to list 
 
 DOWPON, RADAPON 
 
 DACTHAL 
 
 BANVEL 
 
 WEEDONE DP (also 
 contains 2,4-D), 
 WEEDONE 20 
 
 DACONATE, DSMA Liquid, 
 WEED-E-RAD, CRAB-E-RAD, 
 WEED-HOE 
 
 KLEENUP, ROUNDUP 
 
 ISO-CORNOX 64; CHIPCO 
 TURF MCPP; MECOPEX 
 
 VAPAM, VPM 
 
 Too numerous to list 
 
 CHIPCO RONSTAR G 
 
 '/./sf may be incomplete. Inclusion of trademarked names 
 is lor information only and no recommendation to the ex- 
 clusion of others is intended. 
 
A 1.T7 : Z3^ 
 
 Contents / 
 
 Names of herbicides 2 
 
 Cultural practices to control weeds 4 
 
 • fertilizing 
 
 • liming 
 
 • watering 
 
 • mowing • 
 
 • timing of cultural operations 
 
 Selective weed control 6 
 
 • buying herbicides 
 
 • herbicide application 
 
 Herbicide treatments and weed types 8 
 
 • control of weed grasses 
 
 • control of broadleaf weeds 
 
 Tillage and new seedlings or plantings .y^<<^.\^^<<rTT77T>>i^^ 
 
 • tillage and turf establishment if'<^/ ^\^>>\ 
 
 • control of weeds //^/ \^V 
 
 • soil fumigation // ./ \^| 
 
 ■ r JUN 4 1984 n\ 
 
 Turf renovation and spot treatments \-\^i 
 
 • herbicides for renovation 
 
 • spot infestations Vv -4t\w "^ ' >^ ^ 
 
 Equivalents .>s^^0.EP0SVi;4iJ<r. 15 
 
 Response of lawn weeds to herbicides 16 
 
 Drawings of common lawn weeds 18-40 
 
 This Home and Garden bulletin supersedes 
 Lawn Weed Control With Herbicides, 
 Home and Garden Bulletin No. 123, 
 revised April 1971. 
 
 May 1984 
 
 For sale by the Superintendent of Documents, U.S. Government Printing OflSce 
 
 Washington, D.C. 20402 
 
Weed Control in Lawns and Other Turf^ 
 
 The best defense against weeds is dense, vigorously growing turf- 
 grass. Weeds have difficulty in gaining a foothold in such a lawn. To 
 produce this kind of turf, you must select the best varieties of adapt- 
 ed grass species; grow them in good soil; maintain the correct soli 
 acidity; use the proper fertilizer for your growing conditions; water 
 the turf properly; use the correct growing procedure; and control 
 weeds, insects, diseases, and nematodes. In spite of these efforts, 
 weeds often become problems. Weeds may appear if the turf is 
 mechanically disturbed; if the turf is worn by excessive use; and if 
 diseases, insects, or droughts partially reduce the stand. Furthermore, 
 some weed species are particularly strong competitors. 
 
 When weeds occur in lawns there are many methods of control, 
 including use of cultural practices and herbicides. Herbicides are avail- 
 able for control of most of the weeds found in lawns and turf. If they 
 are used according to directions on the label, the recommended her- 
 bicides will not damage plants and the hazard is low to the user, oth- 
 er persons, pets, birds, and wildlife in the area. Always read the direc- 
 tions and precautions on the label of herbicides before use. If improp- 
 er cultural practices are the cause of thin, weedy turf, correct these 
 basic causes as the first step in weed control. 
 
 Cultural Practices to Control Weeds 
 
 Fertilizing The nutrient most often lacking in turf is nitrogen. It and 
 the two other more common fertilizer elements, phosphorus and po- 
 tassium, should be in good supply when turf species are making most 
 rapid growth. Several States recommend ratios of high nitrogen, low 
 phosphorus, and mediurh potassium for repeat use on turf. Consult lo- 
 cal experts about practices to be followed. 
 
 In the northern temperate climate, cool-season grasses should be 
 fertilized more heavily in the fall, with a lighter application or none at 
 
 'Davton L. Klingman (retired), Agricultural Research Service 
 
 (ARS), USDA, Beltsville, Md.; E. O. Burt (retired), Univ. of 
 
 Florida, Ft. Lauderdale; W. H. Daniel, Purdue Univ., 
 
 W. Lafayette, Ind.; C. L. Elmore, Univ. of California, Davis; 
 
 I. A. lagschitz, Univ. of Rliode Island, Kingston: and 
 
 I. I. Murray, ARS, USDA, Beltsville, Md. 
 
all in early spring. Use of nitrogen in summer is less common. Annual 
 rates of nitrogen range from 2 to 6 lb/1,000 square feet. Nitrogen lev- 
 els in the soil should be declining in cool-season grass turf before 
 periods of expected hot or dry weather. 
 
 Fertilize warm-season grasses such as bermudagrass, zoysia, and 
 St. Augustinegrass with nitrogen during the spring, early summer, and 
 early fall months at an annual rate of 5 to 10 lb/1,000 sq. ft. 
 
 Liming A pH in the range of 6.0 to 7.0 is considered best for turfgrass 
 growth because it provides for more favorable nutrient availability and 
 microbial activity. Ground agricultural limestone is frequently needed 
 in acidic soils in the Eastern United States. Need for lime can be deter- 
 mined by soil test. As a generalization in higher rainfall regions, acid 
 sandy soils usually require light applications (about 100 lb/1,000 sq. ft.) 
 of ground or pulverized limestone every 2 or 3 years and clay soils re- 
 quire heavier applications (about 200 lb/1,000 sq. ft.) every 5 to 6 
 years. Lime can be applied at any season; however, late fall or winter 
 is the best time. 
 
 Watering Sandy soils, because of their low moisture-retaining capaci- 
 ty, require frequent watering. Clay soils require less frequent watering 
 but larger amounts of water. Do not water the lawn until grass shows 
 signs of wilt. Then apply enough water, usually about an inch, to wet 
 the soil 6 inches deep or more. Do not apply water faster than it can 
 be taken in by the soil. Avoid watering lightly at frequent intervals; 
 this is wasteful and causes shallow growth of grass roots and stimu- 
 lates germination and growth of weeds. For instance, light, frequent ir- 
 rigation encourages the invasion of annual bluegrass and crabgrass. 
 
 Mowing Mow lawns of most cool-season grasses at least weekly to a 
 height of 2 to 2-1/2 inches. Close mowing, especially in hot weather, 
 weakens cool-season turfgrasses and invites weed invasion. Crabgrass, 
 in particular, can be reduced by the shading effects of the taller, 
 denser growth of permanent grasses on the crabgrass seedlings. Inva- 
 sion of spotted spurge, another warm-season weed, can be reduced 
 by high mowing. 
 
 Warm-season grasses, particularly bermudagrass, require closer 
 mowing than most cool-season grasses. Bermudagrass should be cut 
 frequently to a height of 5/8 inch or less. Others such as zoysia, cen- 
 tipedegrass, and carpetgrass should be mowed to a height of about 1 
 inch. St. Augustinegrass and bahiagrass should be cut at 2-1/2 to 3- 
 1/2 inches. 
 
Mow lawns frequently. Keep the mower blades sharp. Unless 
 growth is excessive and there are weeds setting seed in the lawn, 
 leave the clippings on the grass. A mower with a mulching blade in- 
 creases rate of decomposition of the clippings. Do not let grass grow 
 unusually high. No more than one-third the length of the grass leaf 
 should be removed at a clipping. If a lawn is to be mowed at 2 
 inches, the grass should be mowed before it exceeds 3 inches in 
 height. 
 
 Timing of Cultural Operations In some turf areas, cultural operations 
 require aerating, verticutting, or dethatching to enhance growing 
 conditions. When planning these operations they should be timed to 
 be performed when the turf will regenerate quickly. At the same time 
 these operations should not uncover the soil or leave it bare at the 
 time of year when seeds of crabgrass, annual bluegrass, or goosegrass 
 germinate. These weeds invade rapidly into open areas. 
 
 These management operations should not be performed follow- 
 ing preemergence herbicide applications or the weeds will not be 
 controlled. If the preemergence herbicide bensulide or benefin is ap- 
 plied immediately after verticutting or dethatching, the grass regrowth 
 may be suppressed. 
 
 Selective Weed Control 
 
 Selective herbicides are chemicals that will control most weeds 
 without injuring the turfgrass. Use herbicides only when necessary and 
 as part of a complete lawn management program. Always read and 
 follow the directions on the label. An excess dosage of almost any 
 herbicide will damage lawn grasses, and a herbicide may kill one weed 
 and not affect others. To control some weeds you may need to use 
 herbicides that will temporarily or even permanently injure lawn 
 grasses. 
 
 Buying Herbicides Herbicides are sold in liquid, powder, and granu- 
 lar form. Most of them have common names that are assigned specifi- 
 cally to their chemical names. On the inside front cover of this publi- 
 cation, herbicides used for turf weed problems are listed. Because of 
 the great number of trade names under which these herbicides are 
 sold, the common names are used in the text of this publication. 
 
 The strength of liquid forms of herbicides may be stated on labels 
 as pounds-per-gallon acid equivalent and percent of active in- 
 gredients. The weed-killing strength of other herbicides is stated on 
 the label as percent of active ingredient. Labels on granular herbicides 
 
state the percent of active ingredient and may give the size of lawn 
 area to be treated with the package contents. 
 
 Herbicide Application Granular herbicides are ready to use as pur- 
 chased. Granular herbicide particles are usually relatively large and 
 drift less than liquid sprays. Granular materials are best applied with ei- 
 ther the drop- or spinner-type spreader. Use the spreader setting 
 recommended by the manufacturer or that listed on the herbicide la- 
 bel. 
 
 Extra precautions should be taken in applying fertilizer-herbicide 
 mixtures. Do not overtreat by making a second or third trip around 
 trees and shrubs to give them an extra feeding of fertilizer. Such extra 
 trips can apply too much herbicide and cause injury or death to the 
 trees and shrubs. Do not use the fertilizer-herbicide mixture each time 
 the grass needs fertilizer. 
 
 Add liquid and wettable powder formulations to water and apply 
 as a spray. Use a sprayer that can be adjusted to make a coarse spray 
 at low pressure (less than 35 psi). On very small areas you may use a 
 garden sprinkling can. Care must be taken in handling sprays, especial- 
 ly herbicides such as 2,4-D, dichlorprop, mecoprop, and dicamba. 
 Drift of even small amounts of these can damage trees, shrubs, 
 flowers, and vegetables. Make treatments only when there is little or 
 no wind. Usually 1 to 5 gallons of spray mixture per 1,000 sq. ft. of 
 lawn are used. Within these limits the volume of spray used is not im- 
 portant. It is extremely important, however, to use the proper dosage 
 of herbicide per 1,000 sq. ft. 
 
 The most convenient equipment for applying sprays to small 
 areas is the pressure or knapsack sprayer of 1- to 3-gallon capacity. 
 This type of sprayer provides a fairly consistent volume of spray at 
 low pressure and allows you good control in limiting spray to the tar- 
 get area. Constant container agitation is necessary when using the 
 wettable powder or emulsifiable formulations or they will settle out. 
 
 One method of treating small patches or individual weeds is to 
 use a small paint brush or sponge nailed or wired to a broomstick or 
 dowel. Mix a small amount of herbicide in a container that has a large 
 enough opening so that the sponge or brush can be easily dipped. 
 After dipping, squeeze out the excess by pressing the brush or sponge 
 against the inside of the container. Simply "paint" or dab the weed. 
 Also, such commercial devices are available on the market. When us- 
 ing this method, dilute the herbicide as if it were to be sprayed. Do 
 not use full strength chemicals or turf injury will result. 
 
Do not spray other plants such as flowers or vegetables with 
 equipment that has been used for herbicides. There may be enough 
 herbicide spray residue left in the sprayer to cause injury to these 
 plants. 
 
 Herbicide Treatments and Weed Types 
 
 Most lawn weeds are classed either as grasses or as broadleaf 
 types. The annual grass type includes crabgrass, foxtails, and barnyard 
 grass. Examples of broadleaf types include dandelions, plantains, 
 and chickweed. A narrow-leaf weed that is not a grass is nutsedge. 
 Each type requires different herbicides for effective control. 
 
 Herbicides used for crabgrass are usually effective on most other 
 annual grasses. The herbicides effective for controlling dandelion, plan- 
 tain, and chickweed are usually effective on most of the other 
 broadleaf weeds (see table and drawings at the back). 
 
 There are three types of weed control treatment: 
 
 • Preplanting - a herbicide applied before seeding or sodding turf. 
 
 • Preemergence treatment - the herbicide applied before weed 
 seeds germinate. 
 
 • Postemergence treatment - the herbicide applied after weeds e- 
 merge. Sometimes, a sequence of treatment at definite intervals or 
 repeated treatments are required to kill weeds without excessive 
 injury to the turf. 
 
 Always read instructions on the label and pay particular attention 
 to limitations on use. 
 
 Control of Weed Grasses Crabgrasses and other annual summer 
 grasses may be a problem in lawns in most areas of the United States. 
 You can achieve best control from one of the preemergence herbi- 
 cides applied before seed germination. A good index as to best time 
 for application is when Forsythia is flowering or when lilacs are about 
 to bloom. Another useful index is when soil temperature reaches 
 50°F. In most warm- and cool-season turfgrasses DCPA, benefin, ben- 
 sulide, siduron, and oxadiazon applied before weed seed germinates, 
 and according to directions, provide control. Only siduron can be 
 used on newly seeded turf areas. Other materials have a specified 
 waiting period (2 months or more) before overseeding is recommend- 
 ed. If no rainfall is received within 3 or 4 days after treatment, sprinkle 
 irrigation is recommended. 
 
 DCPA may injure red fescue and dichondra. Benefin may injure 
 bentgrass and dichondra. Bensulide may be used on most turf species. 
 Oxadiazon should not be used on bentgrass, centipedegrass, dichon- 
 
 8 
 
dra, or zoysia; in some areas it will injure perennial ryegrass. Siduron is 
 not recommended for use on bermudagrass and some varieties of 
 bentgrass. 
 
 Some of the other weedy annual summer grasses that may be 
 controlled with these herbicides include barnyardgrass, fall panicum, 
 foxtails, and goosegrass. Goosegrass is usually the most difficult to 
 control. 
 
 For control of such weeds as crabgrass, Paspalum sp., spotted 
 spurge, and most other annual broadleaf weeds in centipede, St. Au- 
 gustine, and zoysia grasses, apply the granular formulation of atrazine 
 in January, February, or March before weeds germinate. Treat soon 
 after planting newly sprigged lawns to reduce competition from 
 weeds. Do not apply to root zone areas of trees and shrubs. 
 
 Postemergence use of methanearsonate herbicides (DSMA, 
 MSMA, CMA, and MAMA), in two to three treatments of 5- to 10-day 
 intervals, provides some control of seedling and juvenile plants of 
 crabgrasses, foxtails, sandbur, and other annual summer grasses. To be 
 effective and to minimize turf injury, soils should have enough mois- 
 ture to support active growth. Also, treatments should be made on 
 days when temperatures will not exceed 85°F. Even so, some tem- 
 porary discoloration of turf is common. Generally, preemergence her- 
 bicides are more reliable for controlling crabgrass. 
 
 Asulam is used for postemergnce control of annual grasses and 
 certain broadleaf weeds in St. Augustinegrass only. Atrazine will also 
 control certain broadleaf and grass weeds when applied either pre- 
 emergence or postemergence in St. Augustinegrass. 
 
 Goosegrass tends to be a problem where soils are compacted 
 and turf is thin. It is an annual whose seeds germinate later than 
 crabgrass in spring and during the summer. Herbicide treatments used 
 for crabgrass control should be reinforced by a second application of 
 one-third to one-half the initial rate 4 to 5 weeks after the first appli- 
 cation to provide better goosegrass control. Most of the herbicides 
 give variable results. Oxadiazon tends to provide more reliable results 
 than the others. It may be best to correct the causes of the problem, 
 and reseed or sod in the fall to allow time for dense turf to develop 
 before the next spring. 
 
 Annual bluegrass tends to be a major problem in closely mowed 
 turf (such as putting greens) and in thin stands or along turf borders. It 
 is a cool-season species whose seeds can germinate throughout the 
 year except in the Deep South. Most preemergence herbicides used in 
 cool-season turfgrasses give only partial control. In some areas bensu- 
 lide is the preferred herbicide. Good turf management practices (infre- 
 quent irrigation and high mowing height) may limit infestation. 
 
Annual bluegrass can be well controlled in bermudagrass in the 
 Southeastern States by pronamide either as a preemergence or post- 
 emergence treatment. Do not overseed treated areas for 90 days 
 after application of pronamide, unless finely ground charcoal is applied 
 before seeding. 
 
 Bermudagrass, quackgrass, zoysiagrass, kikuyugrass, nimblewill, 
 and other perennial grasses that spread by horizontal stems, either 
 below or above ground, are often weeds in cool-season turfgrass and 
 can be controlled by methods to be discussed under turf renovation. 
 Clyphosate is advantageous for spot treatments. Such spreading 
 perennial grasses often have dormant buds at the joints of the spread- 
 ing stems that may not be killed by a single treatment of herbicide. 
 When practical, a second application with 1 to 2 months between 
 treatments increases the chance of eradicating these species. Continue 
 to search for any live plants for many months or years after treatment. 
 Because glyphosate is effective only when applied to leaves, an abun- 
 dance of foliage on the weed grasses at the time of application is 
 necessary for control. Treated spots can be seeded, sprigged, or sod- 
 ded soon after treatment as discussed under "Renovation," page 13. 
 Any reinfestation should be spot-treated as soon as observed. 
 
 Tall fescue, timothy, orchardgrass, and other such perennial 
 bunch grasses, when in fine turf, give a clumpy appearance because 
 of their more rapid growth. If only a few clumps occur they can be 
 removed by cutting under them shallowly with a spade. The bunch 
 grasses can be spot sprayed. The bare spots can be resodded or filled 
 with topsoil and seeded. See renovation treatments. 
 
 Dallisgrass and some other Paspalum species are controlled by re- 
 peated applications of postemergence sprays with DSMA and other 
 methanearsonate herbicides at the highest rate recommended on the la- 
 bel. Some slight discoloration of turf may result temporarily. Do not use 
 on St. Augustine, bahiagrass, carpetgrass, or centipedegrass turf. 
 
 Control of Broadleaf Weeds Broadleaf weed control herbicides are 
 usually applied directly to foliage and stems of actively growing 
 weeds (postemergence treatments). Most should be applied in early 
 fall (to allow grass to fill spaces left by dead weeds) or in the spring. 
 Most broadleaf weeds are controlled by using one of the com- 
 mercially available products containing 2,4-D in combination with one 
 or more of the following: Dicamba, mecoprop, and dichlorprop. 
 
 10 
 
There are only a few broadleaf weeds that will not be con- 
 trolled by these connbinations. In newly seeded turf bromoxynil will 
 control many seedling broadleaf weeds. For weeds not controlled by 
 these herbicides, you may consult your local County Extension agent 
 or garden center representative for specific recommendations. 
 Responses of some common weeds to herbicides are given in the 
 table on pages 1 6 and 1 7. Do not mow or water lawn for at least 2 
 days after treatment. 
 
 If you use a granular material, be sure to follow instructions on 
 the label. It is generally recommended that such formulations be ap- 
 plied when plant leaves are moist by dew in early morning or just 
 after watering the lawn. Herbicide granules retained in water droplets 
 on the leaves are readily absorbed by the leaves. 
 
 A high percentage of lawn weeds are controlled by 2,4-D. How- 
 ever, several common weeds are not controlled by it. Included in this 
 group are a number of weeds that are well controlled Iby dicamba 
 (knotweeds, red sorrel, white clover, henbit, chickweeds, and many 
 others). 
 
 Take special care not to exceed recommended rates with dicam- 
 ba because it may be absorbed from the soil by plant roots of orna- 
 mentals in amounts injurious to shrubs and some trees. For safety, do 
 not treat within the "drip line" of shrubs and trees. 
 
 Speedwells and prostrate spurge are not well controlled with 
 2,4-D and herbicides commonly sold in mixtures with it except where 
 plants are quite young. These weeds can be suppressed by sprays of 
 DCPA applied at about the same time they should be applied for 
 crabgrass control. Bromoxynil applied postemergence on young spurge 
 will further reduce populations. 
 
 Yellow nutsedge is a perennial that reproduces mainly by nutlets 
 underground that may persist in the dormant stage. If you have only a 
 few plants, persistently pull the plants before each mowing date to 
 control them. Heavier stands are controlled with difficulty and often 
 incompletely. Two or three treatments with bentazon, DSMA, or other 
 methanearsonates in late June and July, with 7- to 14-day intervals 
 between treatments, will reduce stands of yellow nutsedge. Repeated 
 heavy treatments with 2,4-D will also reduce stands of yellow 
 nutsedge. Temporary slight discloration of lawn may result. 
 
 Wild garlic produces hardshell bulbs that may lie dormant under- 
 ground and may continue to produce plants for about 3 years. There- 
 
 11 
 
fore, to control this species use three annual treatments with 2,4-D 
 made in late winter or very early spring at the highest rates recom- 
 mended on the label. Low volatile ester formulations are more effec- 
 tive than amine salts. 
 
 Tillage and New Seedlings or Plantings 
 
 Tillage and Turf Establishment Existing turf can be removed by a sod 
 cutter, or in small areas, with a flat shovel. Also, the areas can be cul- 
 tivated with rotary-tillage equipment. Many weeds are easily killed by 
 cultivating and drying. If time is available, fallowing the soil with cul- 
 tivation intervals of 3 to 5 weeks will control many of the weeds aris- 
 ing from seeds and vegetative parts present in the soil. However, til- 
 lage is seldom adequate to control such pernicious perennial species 
 as quackgrass, bermudagrass, zoysia, and nutsedge. Use one of the 
 herbicides, discussed under "Renovation," that has little or no residual 
 toxicity in the soil before tillage when renovating such areas; or use a 
 soil fumigant after tillage. Finally, add needed lime and fertilizer and 
 plant seed in a smooth, firm seedbed. High-quality seed of an adapt- 
 ed turf variety may be broadcast on the surface and raked in or seed 
 may be shallow drilled. It may be advantageous to cover the surface 
 lightly with a straw mulch, peat, or compost. If you broadcast seed on 
 the soil surface, wet the seed and soil (sprinkle irrigate) daily for 7 to 
 14 days until seedling plants are visible. Then water less frequently. 
 
 Control of Weeds Some weeds in new seedings can be partially con- 
 trolled by a proper balance of mowing, irrigation, and fertilization. If 
 seedling broadleaf weeds threaten to shade out turfgrass seedlings, 
 even after one or two mowings, they may be controlled by herbi- 
 cides. A mixture of 2,4-D with other herbicides can be used advan- 
 tageously on cool-season grass seedlings of such species as Kentucky 
 bluegrass, red fescue, and tall fescue if applied at one-quarter to one- 
 third the rate used in established turf. Such treatments should be de- 
 layed 5 weeks or more after seeding. Also, bromoxynil alone or in 
 combination with dicamba has effectively controlled many annual 
 broadleaf weeds in new seedings without any delay in use needed 
 after seeding. 
 
 In spring or early summer seedings, crabgrass, foxtail, or bermu- 
 dagrass plants can be controlled by an application of siduron made on 
 cool-season turf species at seeding time. 
 
 12 
 
Soil Fumigation Soil fumigation before seeding or planting the turf 
 species is a very effective method of controlling persistent w/eeds if 
 used on moist, tilled soil. 
 
 • Metham is a soil fumigant used to kill germinating seeds, rhizomes, 
 tubers, roots, and stems of weeds in soil. 
 
 The soil should be cultivated and kept moist for a week before 
 applying metham. Then treat with 1 to 2 pints of commercial formula- 
 tion in a sprinkling can to each 1 00 sq. ft. of soil using 2 to 5 gallons 
 of water. Immediately sprinkle the treated area with water until soil is 
 wet as deep as control is desired. To increase effectiveness, an airtight 
 cover may be spread over treated area (cover edges with soil) to sub- 
 stitute for the water seal. This greatly increases the effectiveness of 
 the fumigant as a herbicide. You may seed 14 to 21 days after treat- 
 ment. 
 
 • Methyl bromide is a restricted fumigant herbicide that is very 
 poisonous and may be used only by a certified applicator. It is par- 
 ticularly effective for control of pernicious weed species with 
 nutlets, bulbs, corms, and lateral underground stems. It also kills 
 most seeds and disease organisms in the soil. It does not control 
 hard seeds of clover, dichondra, or field bindweed. Methyl 
 bromide must be applied when soil temperature is above 60°F and 
 under a well-sealed airtight cover. Because of the poisonous char- 
 acter of the gas, it can be safely used only if strict precautions are 
 followed. You can remove the cover 2 days after treatment and 
 seed 2 days later. 
 
 Turf Renovation and Spot Treatments 
 
 Sometimes an existing lawn that has weeds and mixed grass 
 species needs to be changed into a turf of superior quality. For exam- 
 ple, a Kentucky bluegrass turf may have been invaded by bentgrass, 
 bermudagrass, zoysia, or quackgrass. These unwanted grass species 
 cannot be controlled selectively in Kentucky bluegrass. Therefore, they 
 must be killed before a new lawn is established. Renovation involves 
 killing or removing the existing vegetation and establishing new turf. 
 
 Select the time of renovation that will favor establishment of the 
 desired turf species (when you expect adequate rainfall to germinate 
 seeds, especially if irrigation is not available, and when competing 
 weeds will be least troublesome). You may need to seek local advice 
 because conditions differ greatly among regions and for turfgrass 
 species. Varieties of turf species should be those best adapted in the 
 region. Under some situations, or with some turf species, sodding or 
 
 13 
 
sprigging is preferable to seeding. Check with your County Extension 
 agent for up-to-date information, especially about grass establishment 
 techniques. 
 
 Herbicides for Renovation A number of herbicides will kill established 
 vegetation and weeds. Some herbicides require no waiting period 
 after treatment before seeding while others leave toxic residues re- 
 quiring waiting periods of 20 to 50 days before seeding. 
 
 No seedbed tillage preparation is required when vegetation is 
 killed by herbicides provided the seed of turf varieties are placed in 
 contact with the mineral soil. The latter is important. A disk-seeder 
 machine will accomplish this task in one pass. If excessive thatch is 
 present, till, verticut, or thoroughly rake it with a thatch rake. Other 
 information under "Tillage," page 12, also applies here. Because ger- 
 minating weed seeds may present severe weed problems where limit- 
 ed tillage is practiced, supplemental weed control is often required. 
 
 • Glyphosate is used as a foliage spray and effectively controls 
 grasses and broadleaf weeds. Plants should have well-developed 
 foliage and be growing actively when sprayed. Glyphosate is 
 translocated throughout the plant and the vegetation should not 
 be mowed, verticut, or cultivated until 3 or more days after treat- 
 ment. Glyphosate is water soluble and is partially washed off 
 plants by rainfall or sprinkle irrigation within 6 hours of treatment. 
 
 Most cool-season grasses and annual grasses are killed by treat- 
 ment with 1 pound acid equivalent per acre of glyphosate. Almost all 
 plants of such strongly spreading grasses as bermudagrass are killed 
 with a single spraying with glyphosate at 4 lb/acre under favorable 
 conditions. In the Middle Atlantic States, two treatments, 1 to 2 
 months apart, at 1-1/2 to 2 lb/acre are slightly more effective on ber- 
 mudagrass and zoysia. Moisture should be adequate to cause 
 development of dormant buds between treatments. Also, to increase 
 control in some areas, the turf can be verticut or cultivated 7 days 
 after treatment and the area can be completely dried out to kill any 
 remaining dormant buds. 
 
 You can seed turfgrasses soon after treatment with glyphosate 
 because it leaves no residues in the soil toxic to germinating grass 
 seeds. Glyphosate does not move laterally in runoff water from the 
 treated area. Prevent sprays or drift from contacting foliage of desir- 
 able plants or injury will result. 
 
 Use control methods described earlier for weeds that may be- 
 come a problem in the new seeding. 
 
 • Amitrole is a foliage-applied, translocated herbicide that will con- 
 trol most annual species and some perennial grass species. Best 
 
 14 
 
control is achieved if weeds are growing vigorously in moist soil. If 
 it does not rain within 5 to 7 days after treatment, apply heavy ir- 
 rigation. Ten to fourteen days after treatment (when grass or 
 weeds are white or brown) the area should be cultivated. This can 
 be done by digging, rototilling, or otherwise loosening and drying 
 treated areas — verticutting, aerating, or raking the area is not 
 enough. If rain or watering occurs within 12 hours after treatment, 
 reduced control will result. If bermudagrass regrows, it should be 2 
 to 3 inches high before retreating. Rototill the area again in 10 
 days and then seed. 
 
 • Dalapon is used for turf renovation in Arizona and California only. 
 Mow any dead vegetation present, irrigate, and wait 2 weeks for 
 new grass growth, then spray with 0.37 oz active ingredient per 
 1,000 sq. ft. (1 lb/acre). After 2 to 3 weeks, water at least 15 
 min/day for 1 week. Wait 4 to 6 weeks, then seed, plug, or sprig 
 new lawn. 
 Verticutting or rototilling, followed by drying of soil, will increase 
 
 control of bermudagrass and other perennial grasses. 
 
 Runoff water can carry dalapon to adjoining turf areas and cause 
 
 injury. 
 
 Spot Infestations Often a spot(s) of coarse grass such as tall fescue in 
 Kentucky bluegrass or pernicous perennials such as bermudagrass, 
 bentgrass, quackgrass, nimblewill, and others will occur in otherwise 
 high-quality turf. These cannot be killed selectively. Methods dis- 
 cussed under "Renovation," particularly glyphosate, can be used to kill 
 these spots so that they can be reseeded, sodded, plugged, or 
 sprigged. Be particularly careful to confine the spray to the spot in- 
 tended to be sprayed. For such weed species as bermudagrass, the 
 sprayed area should extend at least 12 inches beyond the last ob- 
 served bermudagrass plants because of their strong rhizome habit that 
 grows outwardly. Do not use dalapon for spot treatments because 
 runoff water carries the herbicide outside the treated spots to adjoin- 
 ing turf and kills more grass than intended. 
 
 Equivalents 
 
 1 quart = 2 pints = 4 cups = 32 fluid ounces = 946 milliliters 
 
 1 cup = 8 fluid ounces = 16 tablespoons = 237 milliliters 
 
 1 fluid ounce = 2 tablespoons = 29.6 milliliters 
 
 1 pound = 16 ounces = 454 grams 
 
 1 acre = 43,560 square feet = 0.405 hectare (ha) 
 
 1 hectare = 2.47 acres 
 
 15 
 
Response of Lawn Weeds to Herbicides^ 
 
 (Symbols: E = excellent, 
 
 VC = very 
 
 good, G 
 
 = good. 
 
 F = fair, and P = 
 
 poor) 
 
 Weed 
 
 Type of 
 plant 
 
 
 
 ControP 
 
 
 2,4-D 
 
 MCPA 
 
 dicamba 
 
 mecoprop 
 
 Bindweed, field 
 
 Perennial 
 
 G 
 
 F 
 
 F 
 
 G 
 
 Convolvulus arvensis 
 
 
 
 
 
 
 Buttercup, creeping 
 
 Perennial 
 
 G 
 
 E 
 
 G 
 
 C 
 
 Ranunculus repens 
 
 
 
 
 
 
 Chickweed, common 
 
 Annual 
 
 G 
 
 F 
 
 E 
 
 E 
 
 Stellar ia media 
 
 
 
 
 
 
 Chickweed, mouseear 
 
 Perennial 
 
 F 
 
 F 
 
 E 
 
 C 
 
 Cerastium vuigatum 
 
 
 
 
 
 
 Cinquefoil, Canada 
 Potentilla canadensis 
 
 Perennial 
 
 VG 
 
 G 
 
 E 
 
 — 
 
 Cinquefoil, sulphur 
 
 Perennial 
 
 VG 
 
 G 
 
 E 
 
 — 
 
 P. recta 
 
 
 
 
 
 
 Clover, White 
 
 Perennial 
 
 P 
 
 P 
 
 E 
 
 VG 
 
 Trifolium repens 
 
 
 
 
 
 
 Clover, bur 
 
 Annual 
 
 F 
 
 F 
 
 E 
 
 E 
 
 Medicago polymorpha 
 
 
 
 
 
 
 Daisy, English 
 
 Perennial 
 
 P 
 
 P 
 
 E 
 
 F 
 
 Belli s perennis 
 
 
 
 
 
 
 Dandelion 
 
 Perennial 
 
 E 
 
 E 
 
 F 
 
 F 
 
 Taraxacum officinale 
 
 
 
 
 
 
 Dock, curly 
 
 Perennial 
 
 VG 
 
 G 
 
 VG 
 
 F 
 
 Rumex crispus 
 
 
 
 
 
 
 Garlic, wild 
 
 Perennial 
 
 G 
 
 F 
 
 F 
 
 — 
 
 Allium vineale 
 
 
 
 
 
 
 Ground ivy 
 
 Perennial 
 
 C 
 
 F 
 
 G 
 
 — 
 
 Glecoma hederacea 
 
 
 
 
 
 
 Henbit 
 
 Annual 
 
 F 
 
 F 
 
 E 
 
 — 
 
 Lamium amplexicaule 
 
 
 
 
 
 
 Ivy, English 
 
 Perennial 
 
 P 
 
 P 
 
 F 
 
 P 
 
 Hedera helix 
 
 
 
 
 
 
 Knawel, annual 
 
 Annual 
 
 P 
 
 P 
 
 E 
 
 — 
 
 Scleranthus annuus 
 
 
 
 
 
 
 Knotweed 
 
 Annual 
 
 F 
 
 F 
 
 E 
 
 F 
 
 Polygonum aviculare 
 
 
 
 
 
 
 Medic, black 
 
 Annual 
 
 C 
 
 G 
 
 C 
 
 C 
 
 Medicago lupulina 
 
 
 
 
 
 
 Moneywort 
 Lysimachia nummularia 
 
 Perennial 
 
 E 
 
 — 
 
 — 
 
 — 
 
 Nutsedge, purple 
 Cyperus rotundus 
 
 Perennial 
 
 F 
 
 P 
 
 P 
 
 P 
 
 16 
 
Response of Lawn Weeds to Herbicides^— continued 
 
 (Symbols: E = excellent, VC = very good, G = good, F 
 
 = fair, and P = 
 
 poor) 
 
 Type of 
 
 Contror 
 
 
 weea piani 
 
 2,4-D MCPA 
 
 dicamba 
 
 mecoprop 
 
 Nutsedge, yellow 
 
 Perennial 
 
 F 
 
 P 
 
 C. esculentus 
 
 
 
 
 Pennywort, lawn 
 
 Perennial 
 
 VC 
 
 — 
 
 Hydrocotyle rotundifolia 
 
 
 
 
 Plantain, broadleaf 
 
 Perennial 
 
 E 
 
 C 
 
 Plantago major 
 
 
 
 
 Plantain, buckhorn 
 
 Perennial 
 
 E 
 
 C 
 
 P. lanceolata 
 
 
 
 
 Plantain, rugel 
 
 Perennial 
 
 E 
 
 c 
 
 P. regelii 
 
 
 
 
 Posion Ivy 
 
 Woody 
 
 C 
 
 c 
 
 Toxicodendron radicans 
 
 
 
 
 Posion Oak 
 
 Woody 
 
 c 
 
 F 
 
 T. diversiloba 
 
 
 
 
 Puncturevine 
 
 Annual 
 
 VC 
 
 F 
 
 Tribulus terrestris 
 
 
 
 
 Sorrel, red 
 
 Perennial 
 
 p 
 
 P 
 
 Rumex acetosella 
 
 
 
 
 Speedwell, corn 
 
 Annual 
 
 F 
 
 P 
 
 Veronica arvensis 
 
 
 
 
 Speedwell, purslane 
 
 Annual 
 
 G 
 
 P 
 
 V. peregrina 
 
 
 
 
 Spurge, spotted 
 
 Annual 
 
 F 
 
 F 
 
 Euphorbia maculata 
 
 
 
 
 Strawberry, wild 
 
 Perennial 
 
 F 
 
 P 
 
 Fragaria 
 
 
 
 
 Thistle, Canada 
 
 Perennial 
 
 C 
 
 C 
 
 Cirsium arvense 
 
 
 
 
 Violet 
 
 Perennial 
 
 F 
 
 P 
 
 Viola 
 
 
 
 
 Woodsorrel, yellow 
 
 Perennial 
 
 F 
 
 P 
 
 Oxalis stricta 
 
 
 
 
 Woodsorrel, creeping 
 
 Perennial 
 
 P 
 
 P 
 
 O. corniculata 
 
 P 
 E 
 F 
 F 
 F 
 C 
 F 
 E 
 VC 
 F 
 F 
 F 
 C 
 E 
 F 
 F 
 P 
 
 P 
 P 
 
 ^The effectiveness evaluations are given as general susceptibility of the weed to a her- 
 bicide. For further information consult individual labels and local authorities. Further 
 research may result in change in some of the current effectiveness ratings. A dash indi- 
 cates effectiveness is not known. 
 
 17 
 
Large Crabgrass 
 
 Large crabgrass, an annual, reproduces by seed. The stems 
 are stout and vigorous; those that are prostrate root at the 
 joints. Stems are not hairy. The leaf blade and the lower 
 part of the leaf (sheath), which encloses the stem, are 
 hairy on large crabgrass; leaves and sheaths on smooth 
 crabgrass are hairless. Most leaf blades of large crabgrass 
 are 1/4 to 7/3 inch wide. Smooth crabgrass is not as coarse 
 and tall as large crabgrass. Seeds are borne on 3 fo 10 
 branches that radiate from the top of upright stems. The 
 two rows of seed are on opposite sides of the branch. 
 
 18 
 
Smooth Crabgrass 
 
 / 
 
 //'/ 
 
 19 
 
Bermudagrass 
 
 Bermudagrass is an aggressive perennial grass that forms a 
 dense, tieavy sod. It reproduces by prostrate stems (both 
 above and below ground) that root at the joints, and by 
 seed. Below-ground stems are hard, scaly, and sharp point- 
 ed. Above-ground stems are gray green and most of their 
 surface is hairless. There are long hairs at the edges just 
 above the junction of the leaf blade and the sheath (the 
 part of the leaf that encloses the stem). Bermudagrass 
 often has two sheaths attached to a single joint. Seeds are 
 borne on three to five branches that radiate from the end 
 of a flattened stem; the two rows of seeds on each branch 
 are pressed closely against one side of the branch. 
 
 20 
 
Coosegrass 
 
 Coosegrass is an annual that reproduces by seed. In gen- 
 eral appearance, it has some resemblance to crabgrass. 
 Stems are prostrate and without hairs, like those of 
 smooth crabgrass. Crabgrass stems root at the joints; 
 goosegrass stems do not. The pale-green leaf blades usual- 
 ly are without hairs and are 3 to 12 inches long; they may 
 be folded. Seeds are borne on 2 to 10 branches that radi- 
 ate from near the top of the stem. There are two rows of 
 seeds, both of which are on one side of, the branch. 
 
 21 
 
Dallisgrass 
 
 Dallisgrass is a perennial vv/fh short rhizomes that gives a 
 clumped appearance in sparse stands. Stems are 18 to 60 
 inches tall and without hairs except at the ligules and on 
 the crowded spikelets that are on one side of the rachis. 
 Seeds are borne in 3 to 9 racemes per stem that are loose- 
 ly ascending or spreading. It is found in the Atlantic Coast 
 States, southward from New jersey and Missouri, and 
 across the southern border States. 
 
 22 
 
Quackgrass 
 
 Quackgrass is a perennial noxious weed that reproduces 
 by seed and spreading underground stems. New shoots 
 and roots arise from joints on the underground stems. 
 Aboveground stems, 18 to 36 inches tall, are smooth with 
 three to six joints. Leaves have auricles, ligule V32 inch 
 long, hairy lower sheath and upper sheaths without hair or 
 nearly so. Leaf blades are soft, flat, with crowded fine ribs. 
 Seeds are borne in a single spike per stem, with three to 
 seven short-awned florets per spikelet. It is a noxious 
 weed found throughout the United States except the 
 southern area. 
 
 23 
 
Nimblewill 
 
 Nimblewill, a perennial, reproduces by seed and by stems 
 that root at the lower joints. Growth that develops from 
 rooting stems forms dense patches W inches or more in 
 diameter. The lower part of the stem is semiprostrate; 
 upper parts curve upwards. The slender, branching stems 
 are not hairy. Leaf blades are short, flat, and hairless. The 
 stems that bear the seeds are branching and 2 to 6 inches 
 long. Seeds are very fine and borne singly. 
 
 24 
 
Barnyardgrass 
 
 Barnyardgrass is a summer annual that reproduces by seed 
 and is a problem in new seedings. Stems are stout, erect 
 to semiprostrate, often branching from the base, seldom 
 more than 3 feet in height. It has no ligule or auricle. Leaf 
 blades are hairless, elongate, and light green. The head is 
 branched, erect to nodding, green to purplish tinged, and 
 4 to 8 inches long. It tolerates wet sites and is found 
 throughout the Unted States except the extreme 
 southeastern area. 
 
 25 
 
Annual Foxtail Grasses 
 
 The Foxtails shown are summer annual grasses. They 
 reproduce only by seed. Yellow foxtail (A) is the species 
 most often found in newer lawns. In mowed lawns, yellow 
 foxtail produces a mat of foliage and seed heads. The stem 
 bases usually are flattened and reddish. The stems are usu- 
 ally 6 to 12 inches high. The leaves are flat but may have a 
 spiral twist; they have long hairs where the leaf joins the 
 leaf sheath enclosing the stem. The growing season is 
 similar to that of crabgrass and control methods are the 
 same lor both weeds. Green foxtail (B) has round stems 
 that branch at the base and are W to 20 inches high. 
 Heads are erect to slightly nodding, densely flowered, usu- 
 ally green to purple colored, and tapers slightly toward the 
 summit. Ciant foxtail (C) is similar in many ways to green 
 foxtail, except it is taller, the stem weaker and often 
 lodged, the head is more lax and nodding, and the leaf 
 blades often are softly hairy beneath. It is seldom a weed 
 in lawns. 
 
 26 
 
Field Sandbur 
 
 Field sandbur is a summer annual grass that reproduces by 
 seed that are borne in burs in terminal spikes. It is trou- 
 blesome in lawns, gardens, crops, and waste places mainly 
 because the spiny burs cause discomfort to persons and 
 animals. Stems are erect and often spreading and mat-like, 
 6 to 24 inches long. It is found mostly in sandy soils 
 along the South Atlantic Coastal Plain from Virginia to 
 Texas and westward from Arkansas to California. 
 
 27 
 
Yellow Woodsorrel 
 
 Yellow woodsorrel, a perennial, reproduces by seed. It is a 
 low-growing plant, 4 to 12 inches tall. The weak stems 
 branch at the base and may root at the joints. Leaves are 
 divided into three folded, heart-shaped leaflets that radiate 
 from the end of a long, slender leaf stalk. Leaves are sour 
 tasting. The yellow flowers have five petals and occur in 
 clusters. 
 
 28 
 
Yellow Nutsedge 
 
 Yellow nutsedge, incorrectly called nutgrass, is a grass-like 
 perennial weed. It reproduces by seed and tubers on the 
 underground lateral stems. Mature plants have nut-like 
 tubers at the tips of the lateral stems. Above-ground stems 
 grow erect and are triangular in cross section and 
 yellowish-green in color. Looking down on the plant, the 
 leaves appear in three ranks corresponding to the triangu- 
 lar stem rather than two ranks as in grasses. Nutsedge is 
 found in lawns in low, wet areas and in lawns that are 
 watered excessively in the summer. 
 
 29 
 
Wild Garlic 
 
 Wild garlic is a perennial bulbous herb. It reproduces by 
 bulbs, bulblets, and seed. The stem is stiff, erect, leafy to 
 near the middle, and 12 to 50 inches tall. Leaves are 2- 
 ranked, with sheathing bases, the leaf blades circular and 
 hollow in cross section, striped, the younger ones easily 
 flattened and slenderly tapering. Plants form four types of 
 bulbs: aerial bulblets at end of upright stem, underground 
 hard shell bulbs (dormant) that have a single bladeless 
 storage leaf that contains a growing point at its base, cen- 
 tral bulbs, and soft offset bulbs. 
 
 30 
 
Prostrate Knotweed 
 
 Prostrate knotweed is a survmer annual weed that repro- 
 duces by seed. Stems are 4 to 40 inches long, prostrate or 
 loosely ascending, the main stem corrugated, much- 
 branched, and mostly forming mats from thin taproots. 
 Leaves are alternate, sharp-pointed to rounded at the end, 
 narrowed at the base, blue-green, lanceolate, linear to ob- 
 long, 3/16 to 7 inch long and from 7/76 to 5/76 inch wide. 
 It is found throughout the United States. 
 
 31 
 
Spotted Spurge 
 
 Spotted spurge, also known as prostrate spurge, is a sum- 
 mer annual reproduced by seed. Stems are slender, pros- 
 trate or ascending, branching from near the base, forming 
 mats 4 to 36 inches in diameter, soft, hairy, and often red- 
 dish, and have a milky juice. Leaves are opposite, 3/76 to 
 5/8 inch long, ovate to oblong in shape, and often 
 purple-mottled in appearance. It is distributed throughout 
 the Eastern and Central States, the Pacific Coast, and a few 
 areas in Idaho and Arizona. 
 
 32 
 
Common Chickweed 
 
 Mouseear Chickweed 
 
 |/«6 
 
 Common chickweed and mouseear chickweed are similar 
 in habit growth. Common chickweed is a low-spreading 
 plant, and mouseear chickweed is partly spreading to 
 erect. Leaves on both plants are small, single, and opposite 
 each other on the stems. Flowers on both are small; the 
 petals are white and fine. But there are distinct differences: 
 (V Leaves of common chickweed are broadly oval, point- 
 ed at the tip, not hairy, and are borne on short leaf stalks; 
 leaves of mouseear chickweed are very hairy, more 
 elongated than round, and attached directly to the stem. 
 (2) Flower petals are slightly notched on mouseear 
 chickweed, and deeply notched on common chickweed. 
 Common chickweed is an annual or winter annual that 
 reproduces by seed and by creeping stems that root at the 
 joints. Mouseear chickweed is a perennial that normally 
 reproduces by seed; occasionally, it reproduces by root 
 development on lower branches. 
 
 33 
 
Ground Ivy 
 
 
 Ground ivy, a perennial, reproduces by seed and by creep- 
 ing stems. Stems that are prostrate root at the joints; 
 those that are upright give rise to long leal stalks. Stems 
 have lour sides. The bright green leaves are almost round 
 with round-toothed edges, and Vi to 7'/? inches in diame- 
 ter. Flowers are small, bluish purple, lunnel shaped, and 
 borne in small clusters in the axils of the leaves. 
 
 34 
 
![ 
 
 Henbit 
 
 Henbit is a winter annual that reproduces by seed and, 
 occasionally, by rooting at the joints where stems touch 
 the ground. Stems are 4 to 6 inches tall, slender, hairless, 
 and four-sided. Leaves are oppostie each other on the 
 stems, and are hairy with rounded teeth. Lower leaves are 
 borne on leaf stalks; upper leaves are attached directly to 
 the stem and clasp the stem. Flowers are pinkish to pur- 
 ple. 
 
 35 
 
Purslane Speedwell 
 
 Purslane speedwell is a winter annual that reproduces by 
 seed. Its root system is quite fibrous. The small, white 
 flowers are located in the axils of the upper leaves. The 
 seed pod is flat, heart shaped, and about 1/8 inch wide. 
 The weed is noticed especially in early spring when 
 blucgrass is just starting to grow well. 
 
 36 
 
Common or Corn Speedwell 
 
 Common or corn speedwell is a winler annual that repro- 
 duces by seed. Its leaves are more oval than those of 
 purslane speedwell and are notched on the margins. The 
 flower petals are blue, and the whole plant is covered 
 with tiny hairs. The heart-shaped seed capsule may be 7/4 
 inch wide. Like purslane speedwell, this weed is found 
 growing in lawns in early spring when bluegrass is making 
 vigorous growth. 
 
 37 
 
Plantains 
 
 Buckhorn, broadleaf, and blackseed plantains commonly 
 found in lawns are perennial plants that reproduce only by 
 seed. All have erect, leafless stems that terminate with a 
 flower spike. (A) Buckhorn plantain leaves are all basal in a 
 rosette, the blades are slender, lanceolate, with 3 to 5 
 prominent veins tapering into the petiole. This weed is 
 found throughout the United States with heaviest concen- 
 trations in the Middle Eastern States eastward from Nebras- 
 ka and Kansas. (B) Broadleaf plantain has broadly ovate 
 leaves, about 2 to 12 inches long, that form a rosette. The 
 blades are thick, rough on one or both sides when dry, 
 with minute hairs. The petioles are broad, usually green 
 (no purple tinge), and hairy at the base. It is found 
 throughout the United States. (O Blackseed plantain has 
 broadly elliptic to oval leaves, about 2 to 8 inches long, 
 that form a basal rosette. The blade is simple, thin, pale, 
 hairless to slightly hairy, usually wavy-edged, petiole is 
 margined, at base usually hairless and tinged with purple. 
 It is found in the eastern half of the United States. 
 
 38 
 
li 
 
 Red Sorrell 
 
 Red sorrell is a perennial that reproduces by creeping 
 rootstocks and seed. It gets its name from the reddish 
 appearance of the seed head. The rootstocks are shallow. 
 The leaves are 1 to 2 inches long, thick with smooth sur- 
 face, and sour tasting. The weed is seen mostly in the 
 spring and fall when it is cooler. It persists in areas of poor 
 drainage and acid soil conditions. 
 
 39 
 
Dandelion 
 
 Dandelion is a perennial herb from a thick taproot with 
 many-branched crowns, with milky juice, and it repro- 
 duces by seed. Shallowly cut roots produce new shoots. 
 Stem is very short and wholly underground, producing a 
 rosette of feaves at the ground surface. Leaves vary in 
 shape, from lobeless or entire to deep-cut lobes. Flower- 
 heads are golden-yellow, 1 to 2 inches in diameter in 
 flower, solitary at the end of a naked hollow stalk 2 to 30 
 inches long. It is found throughout most of the United 
 States. 
 
 40 
 
Use of Pesticides 
 
 This publication is intended for na- 
 tionwide distribution. Pesticides are 
 registered by the Environmental Pro- 
 tection Agency (EPA) for country- 
 wide use unless otherwise indicated 
 on the label. 
 
 The use of pesticides is governed by 
 the provisions of the Federal Insecti- 
 cide, Fungicide, and Rodenticide Act, 
 as amended. This act is administered 
 by EPA. According to the provisions 
 of the act, "It shall be unlawful for 
 any person to use any registered 
 pesticides in a manner inconsistent 
 with its labeling." (Section 12(a) (2) 
 O) 
 
 The optimum use of pesticides, both 
 as to rate and frequency, may vary 
 in different sections of the country. 
 Users of this publication may also 
 wish to consult their Cooperative Ex- 
 tension Service, State agricultural ex- 
 periment stations, or county exten- 
 sion agents for information applica- 
 ble to their localities. 
 
 The pesticides mentioned in this 
 publication are available in several 
 different formulations that contain 
 varying amounts of active ingredient. 
 Because of these differences, the 
 rates given in this publication refer 
 to the amount of active ingredient, 
 unless otherwise indicated. Users are 
 reminded to convert the rate in the 
 publication to the strength of the 
 pesticide actually being used. For ex- 
 ample, 1 pound of active ingredient 
 equals 2 pounds of a 50-percent for- 
 mulation. 
 
 The user is cautioned to read and 
 follow all directions and precautions 
 given on the label of the pesticide 
 formulation being used. 
 
 Federal and State regulations require 
 registration numbers. Use only pesti- 
 cides that carry one of these regis- 
 tration numbers. 
 
 Federal and State regulations require 
 registration numbers. Use only pesti- 
 cides that carry one of these regis- 
 tration numbers. 
 
 USDA publications that contain 
 suggestions for the use of pesticides 
 are normally revised at 2-year inter- 
 vals. If your copy is more than 2 
 years old, contact your Cooperative 
 Extension Service to determine the 
 latest pesticide recommendations. 
 
 The pesticides mentioned in this 
 publication were federally registered 
 for the use indicated as of the issue 
 of this publication. The user is cau- 
 tioned to determine the directions 
 on the label or labeling prior to use 
 of the pesticide. 
 
 Follow 
 Pesticides 
 Label Exactly 
 
 i^U.8. GOVERNMENT PRINTING OFFICE: 198i» if21 227 10016 
 
 41 
 
ir 
 
ill 
 
UNIVERSITY OF FLORIDA 
 
 3 1262 08584 2887