Annual bluegrass (Poa annua) is a small, tufted to clumped winter annual grass. Leaf blades are smooth on both surfaces, with two distinct, clear lines, one on each side of the midrib. Leaf tips are keeled or boat shaped. The ligule is membranous. Spikelets are light green to whitish without cottony hairs. They are arranged on branches, one to two per node. Flowers form in dense to open clusters. Reproduction of annual bluegrass occurs by seed.
Herbicide Options for Controlling Annual Bluegrass in Florida Turfgrass
Annual bluegrass is considered a winter annual. Therefore, it starts to emerge late in the fall when soil temperatures are consistently between 60°F and 70°F. It is at this time that having preemergence (PRE) herbicides on the ground will help to minimize annual bluegrass populations. Due to a prolonged emergence period, postemergence (POST) herbicides should be used as a complement to PRE herbicides and not as a unique control tool. In this way, POST herbicides will control annual bluegrass individuals that escape PRE control. (Always refer to the label for specific uses, application rates, turfgrass tolerance, and application timing.)
Bermudagrass
Preemergence: benefin, benefin+oryzalin, benefin+trifluralin, bensulate+oxadiazon, DCPA, dimethenamid-P, dithiopyr, ethofumesate (only dormant overseeded), fenarimol, indaziflam, metolachlor, napropamide, oryzalin, oxadiazon, pendimethalin, prodiamine, prodiamine+isoxaben, prodiamine+sulfentrazone, proamide, simazine
Postemergence: amicarbazone, bispyribac-sodium (only dormant overseeded), foramsulfuron, metribuzin, pronamide, rimsulfuron, simazine, sulfometuron, sulfosulfuron, trifloxysufluron
St. Augustinegrass
Preemergence: atrazine, benefin, benefin+oryzalin, benefin+trifluralin, DCPA, dimethenamid-P, dithiopyr, ethofumesate, indaziflam, metolachlor, napropamide, oryzalin, oxadiazon, pendimethalin, prodiamine, prodiamine+isoxaben, simazine
Postemergence: amicarbazone, atrazine, ethofumesate, simazine, sulfosulfuron
Centipedegrass
Preemergence: atrazine, benefin, benefin+oryzalin, benefin+trifluralin, DCPA, dimethenamid-P, dithiopyr, indaziflam, metolachlor, napropamide, oryzalin, pendimethalin, prodiamine, prodiamine+isoxaben, prodiamine+sulfentrazone, simazine
Postemergence: amicarbazone, atrazine, clethodim, simazine, sulfosulfuron
Bahiagrass
Preemergence: benefin, benefin+oryzalin, benefin+trifluralin, DCPA, dimethenamid-P, dithiopyr, indaziflam, metolachlor, napropamide, oryzalin, pendimethalin, prodiamine, prodiamine+isoxaben, prodiamine+sulfentrazone
Postemergence: sulfometuron
Seashore Paspalum
Preemergence: dimethenamid-P, dithiopyr, indaziflam, oryzalin, oxadiazon, pendimethalin, prodiamine, prodiamine+isoxaben, prodiamine+sulfentrazone
Postemergence: amicarbazone,
Zoysiagrass
Preemergence: atrazine, benefin, benefin+oryzalin, benefin+trifluralin, bensulate+oxadiazon, DCPA, dimethenamid-P, dithiopyr, indaziflam, metolachlor, oryzalin, oxadiazon, pendimethalin, prodiamine, prodiamine+isoxaben, prodiamine+sulfentrazone, simazine
Postemergence: amicarbazone, atrazine, formasulfuron, simazine, sulfosulfuron, trifloxysulfuron
Perennial Ryegrass
Preemergence: dimethenamid-P, dithiopyr, ethofumesate (dormant overseeded bermudagrass), fenarimol, oxadiazon, pendimethalin, prodiamine, prodiamine+isoxaben, prodiamine+sulfentrazone
Postemergence: bispyribac-sodium (dormant overseeded bermudagrass)
Refer to the publication Pest Control Guide for Turfgrass Managers at http://turf.ufl.edu/pdf/2012_UF_Pest_Control_Guide.pdf for brand names associated with chemical names listed.