HORSEWEED

**

Not for application to residential lawns.

Footnotes:

(1)

Turfgrass Codes:

ba

bahiagrass

bc

bentgrass, creeping

be

bermudagrass

bk

bluegrass, Kentucky

c

centipedegrass

f

fescue, tall

r

ryegrass, perennial

sa

St. Augustinegrass

z

zoysiagrass

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No turfgrass in the database is completely tolerant. Check label to see if chemical can be used at a reduced rate or during the dormant season on your turfgrass.

(2)

Efficacy Ratings:

E

excellent control (90 to 100%)

G

good control (80 to 90%)

F

fair control (70 to 80%)

Efficacy ratings are based on herbicide trials performed by weed scientists at North Carolina State University between 1997 and 2007. The number of trials included in the efficacy ratings is displayed in the next-to-last column. The higher this number, the more confidence can be placed in the efficacy values. Trials may have involved sequential applications of one or more chemical. Details of individual trials (herbicide rates, dates of application, environmental conditions at time of application, etc) can be viewed on the TurfFiles web site, through the Turf Weed Management Decision Aid.

Efficacy ratings for chemicals lacking trial data are from “Pest Management Strategic Plan for Turfgrass in the Southern United States,” summary of a workshop for turf experts from multiple universities held in Griffin, GA in October, 2004 and sponsored by the Southern Region Integrated Pest Management Center.

(3)

Recommendations of specific chemicals are based upon information on the manufacturer's label and performance in a limited number of trials. Because environmental conditions and methods of application may vary widely, performance of the chemical will not always conform to the safety and pest control standards indicated by experimental data. The order in which brand names are given is not an indication of a recommendation or criticism.

Recommendations for the use of agricultural chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services does not imply endorsement by North Carolina State University or discrimination against similar products or services not mentioned. Other brand names may be labeled for use on turfgrasses. Individuals who use agricultural chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact your county's Cooperative Extension agent.