Getting Home Lawns Ready for Spring Green Up.
A spring preemergent herbicide application can help with controlling weeds in lawn.
Atrazine Rate 1-2 qt/a
Atrazine is a common preemergent herbicide that is used to prevent summer weeds. It can be used to a wide range of broad leaf weeds, sandspur, and suppresses crabgrass.
Pendimethalin (Pendulum) – Rate – rates vary by product. Use product label
Pendimethalin control annual grasses, like crabgrass and certain annual broad leaf weeds
SPRING
Apply herbicides to control summer annual weeds such as crabgrass and goosegrass prior to soil temperatures reaching 55° F. Recommended dates are March 1 to 20 in north Georgia and February 15 to March 15 in south Georgia.
Postemergence herbicides are applied after annual weeds emerge or when new growth or regrowth of perennial weeds appears. Follow these guidelines for better weed control and improved turfgrass tolerance:
- Apply postemergence herbicides in the fall and late spring months. Air temperatures are cooler at this time of year, resulting in better turfgrass tolerance to herbicides. Also, perennial and many annual weeds are actively growing during these times of year and are easier to control with postemergence herbicides.
- Do not apply postemergence herbicides to turfgrasses and weeds that are stressed due to high temperatures or drought. Turfgrass tolerance to postemergence herbicides decreases at air temperatures greater than 90° F or when turfgrasses are drought-stressed. Also, weed control is poorer when herbicides are applied to weeds in a stressed condition than when applied to actively growing weeds.
- Do not apply postemergence herbicides during the green-up (transition from winter dormancy to active growth) process of warm-season turfgrasses. The risk of injury from postemergence herbicides is greater during the green-up process than when the turfgrass is fully dormant or actively growing.
Herbicide Use Tables
Visit www.ent.uga.edu/pest-management for the most up-to-date herbicide information. Always go by the label, even if it differs from the information presented here.
| Turfgrass Tolerance to Preemergence Herbicides | |||||||
| PREEMERGENCE HERBICIDES |
TURFGRASSES | ||||||
| Kentucky Bluegrass | Bermuda | Bahiagrass | Centipede-grass | Tall Fescue | St. Augustine-grass | Zoysiagrass | |
| atrazine | S | T(D) | I | T | S | T | I-T |
| benefin | T | T | T | T | T | T | T |
| benefin + oryzalin | T | T | T | T | T | T | T |
| DCPA | T | T | T | T | T | T | T |
| dithiopyr | T | T | T | T | T | T | T |
| oryzalin | T | T | T | T | T | T | T |
| pendimethalin | T | T | T | T | T | T | T |
| prodiamine | T | T | T | T | T | T | T |
| T = Tolerant; T(D) = Tolerant only when turfgrass is dormant; S = Sensitive, DO NOT use this herbicide; I = Intermediately tolerant, use herbicide with caution at reduced rates. | |||||||
| Turfgrass Tolerance to Postemergence Herbicides | |||||||
| POSTEMERGENCE HERBICIDES |
TURFGRASSES | ||||||
| Kentucky Bluegrass | Bermuda | Bahiagrass | Centipede-grass | Tall Fescue | St. Augustine-grass | Zoysiagrass | |
| atrazine | S | T(D) | I | T | S | T | 1-T |
| bentazon | T | T | T | T | T | T | T |
| carfentrazone | T | T | T | T | T | I | T |
| fenoxaprop | T | S | S | S | T | S | I |
| foramsulfuron | S | T | S | S | S | I | I |
| fluroxypyr | T | T | T | T | T | T | T |
| glyphosate1 | S | T(D) | S | S | S | S | S |
| halosulfuron | T | T | T | T | T | T | T |
| 2,4-D + MCPP | T | T | T | I | T | S-I | T |
| 2,4-D + MCPP + dicamba | T | T | T | I | T | I | T |
| MCPP | T | T | T | I | T | S | T |
| imazaquin | S | T | S | T | S | T | T |
| quinclorac | T | T | S | S | T | S | T |
| sulfosulfuron | T | T | I | T | S | T | T |
| sulfentrazone | T | T | T | T | I | S | T |
| trifloxysulfuron | S | T | S | S | S | S | T |
| sethoxydim | S | S | S | T | S | S | S |
| T = Tolerant; T(D) = Tolerant only when turfgrass is dormant; S = Sensitive, DO NOT use this herbicide; I = Intermediately tolerant, use herbicide with caution at reduced rates.
1 Use glyphosate on dormant bermudagrass, for spot treatments or for edging. |
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| Weed Control Schedule for Home Lawns | ||
| Time of Application | Weeds | Remarks1 |
| Late February to mid-March | Crabgrass, goosegrass, sandbur | Apply preemergence herbicide. |
| April to July | Annual and perennial broadleaf weeds | Apply 2,4-D + MCPP; 2,4-D + MCPP + dicamba; MCPP + 2,4-D + dicamba; or MCPP to actively growing broadleaf weeds. |
| May to July | Crabgrass, goosegrass, sandbur, dallisgrass, bahiagrass, nutsedge | Apply herbicides to control escaped grass weeds and suppress nutsedge. In centipedegrass, use sethoxydim or sulfosulfuron to control escaped grass weeds. Imazaquin, bentazon, or sulfosulfuron can be used to control emerged nutsedge(s). In bermudagrass and zoysiagrass, these herbicides, foramsulfuron, quinclorac, and trifloxysulfuron may be applied. |
| Mid-August to mid-October | Annual bluegrass, henbit, chickweed | Apply preemergence herbicide. DO NOT apply to lawns to be overseeded. |
| November to March | Wild garlic, winter annual broadleaf weeds | Apply 2,4-D + MCPP; 2,4-D + MCPP + dicamba; or MCPP + 2,4-D + dicamba in late November or December when temperatures are above 50 degrees F. Add 0.3 oz surfactant per gallon of spray mix when treating wild garlic. Repeat treatment in February for improved wild garlic control. Imazaquin can be used to control wild garlic. Apply imazaquin only after turfgrass dormancy but before spring green-up. |
| November to mid-February | Winter annual weeds | Apply atrazine to centipedegrass, St. Augustine-grass and DORMANT bermudagrass for control of annual bluegrass, henbit, hop clovers, etc. DO NOT apply over the root zone of desirable ornamentals. |
| 1 Refer to the “Turfgrass Weed Control for Homeowners” section in the current homeowner’s edition of the Georgia Pest Management Handbook for more information. | ||