Weed Identification FTGA Turf Seminar Port St. Lucie, FL February 13, 2020
Golf Session
Dr. Phil Busey 954‐579‐3932
Remember:
South Florida Turf Expo March 26, 2020
flrecturf.eventbrite.com
Why identify weeds?
It’s important to know the weed species because if chemicals are used to control them, only some products are effective.
Weeds are indicators of environmental conditions which may need adjustment by management.
Consistent primary cultural practices (mowing, irrigation, and fertilization) grow the densest bermudagrass turf with minimal weed activity. These practices are done anyway, so gentle adjustment may be all that is needed.
Some weeds are beneficial as nectar sources, provide other wildlife benefits, and can lessen soil erosion.
Some weeds can support play, are not noticeable, and their removal may be ugly.
Other weeds that are invasive exotics should be removed everywhere so they do not to spread in natural areas.
Some weeds are a hazard (poisonous, skin irritants, or puncture risks) or other nuisances, e.g., on clothing.
Some turfgrasses can also be weeds, such as off-types of the same species, so we need to be able to identify mixtures of different kinds of turfgrasses.
Users or your boss may ask about weeds. Having the name is a reasonable start for good communications and shows your attention to details.
Weeds are interesting and a part of life.
philbusey.com
Trailing indigo Purple nutsedge
Diamondflower Pectis (cinchweed)
Southern sida False buttonweed
Poa annua Dollarweed
Goosegrass seeds Goosegrass seedlings
Major groups of weeds Grasses Sedges Broadleaf weeds Others
Families of weeds Grass family Sedge family Sunflower family Pea family Coffee family
Weeds identified by Sight recognition Browsing Dichotomous key Technical characteristics
Technical characteristics Leaves arranged alternate or opposite Leaves simple or compound Pinnately or palmately compound leaves Bunch-type or spreading Hairs, spines, tendrils present Leaf margin smooth or serrate Leaf tip rounded or pointed Flower showy or chaffy Flowers in a specialized head Fruit a flat pod or berry or winged
Resources Weeds of Southern Turfgrasses, $14.00:
https://extension.uga.edu/publications.html
edis.ifas.ufl.edu florida.plantatlas.usf.edu
idweed.com
Examples and keywords
Crabgrasses — soft, grayish leaves
Green kyllinga (a sedge) — shiny, bur-like
Seashore paspalum — paired racemes
Bull paspalum — bunch type, rounded seeds
Carpetgrass — wide, flattish leaves
Tropical signalgrass — stiff, shiny leaves
Spurges — milky latex
Torpedograss — hairy leaf sheaths
Crowfootgrass — spreading, comb-like head
Goosegrass — bunch grass, comb-like head