ALABAMA A&M and AUBURN UNIVERSITIES

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ZORIAL RECEIVES EMERGENCY LABEL FOR ALABAMA

AUBURN, FEB. 19---For the sixth consecutive year, the Environmental Protection Agency (EPA) has approved an emergency label for Alabama to permit the use of Zorial in bermudagrass pastures and hayfields.

On Feb. 11, Alabama was granted an emergency exemption by the EPA for the use of Zorial Rapid 80 (norflurazon) to control crabgrass, broadleaf signalgrass and goosegrass in newly established hybrid bermudagrass hayfields. The exemption permits the use of Zorial in bermudagrass pastures until July 31.

Zorial, a preemergence herbicide by Novartis Crop Protection, Inc., is labeled for several other crops including cotton, soybeans and peanuts. This herbicide should be applied in existing stands of bermudagrass in late winter or spring prior to seed germination of the target annual grasses. Crabgrass begins to germinate in early February in South Alabama, mid-February in Central Alabama and early March in North Alabama. Broadleaf signalgrass and goosegrass will germinate a few weeks later in North and Central Alabama.

"Since these weeds can start to emerge in many sites now, landowners should make applications in the next several weeks," says Dr. John Everest, Extension WeedScientist with the Alabama Cooperative Extension System. "If treatment is delayed, emerged grasses will not be controlled by this treatment."

Landowners who will be establishing new bermudagrass pastures or hayfields this year can also use Zorial to control annual grasses. Zorial should be applied immediately after sprigging and before seed germination. This herbicide treatment will reduce the number of grassy weeds competing with the developing bermudagrass.

In newly established sites, Zorial Rapid 80 should be applied as a broadcast treatment using ground equipment at the rate of 0.6 to 0.75 pounds of the dry flowable material per acre in a minimum of 10 gallons of water per acre. Bermudagrass sprigs should be planted 2 inches deep in a well-prepared seedbed prior to application.

On established stands of hybrid bermudagrass, Zorial Rapid 80 can be applied at the rate of 0.75 -1.5 pounds of the dry flowable material per acre. Use lower rate on coarse textured (sands to sandy loam) soils and higher rate on heavy textured (clay) soils and/or established stands, says Dr. Donald Ball, Extension agronomist-forages. Zorial shouldn't be used on sites where the water table is within 30 feet of the surface.

Zorial inhibits the formation of yellow pigments in plants, resulting in the breakdown of chlorophyll. Smallsensitive weeds and grasses turn white due to loss of chlorophyll and die. Some bleaching or whitening may be observed in bermudagrass growing in treated areas. This symptom is cosmetic and temporary, lasting 30 to 40 days. Yield and survival of bermudagrass is not affected when Zorial is applied at recommended rates.

Landowners should avoid excessive overlapping in bermudagrass hayfields. Overlapped areas of bermudagrass will have prolonged injury. Zorial should not be applied with liquid nitrogen or fertilizer. No surfactant or crop oil is needed with this preemergence treatment.