herbicides

Annual weeds establish from seed and complete their lifecycle in one year. Summer or warm-season annual weeds (like crabgrass) establish in spring, grow actively in summer, and die out in fall. Winter or cool-season annual weeds (like annual bluegrass) establish in fall, grow from fall to spring, and complete their lifecycle in warm temperatures in late spring. 

The introduction of new turf herbicides will continue to enable practitioners to control troublesome weeds. In 2010, turf managers will see several new options for weed control from novel active ingredients, combination products, and label amendments. The following article contains an unbiased view on these products and discusses efficacy for turfgrass weed control.

Celsius (thiencarbazone + iodosulfuron + dicamba)

Often one of our biggest problems in the spring is fertilizing turf too early. Early application of fertilizer can lead to early green up. Though this may please the client, turf that greens up early can be more susceptible to damage by late cold weather. Early fertilization may predispose the turf to disease problems. Also, nitrogen applied too early may not be taken up by plant roots which are still dormant. This nitrogen can be lost by leaching and runoff.

Hand-held and backpack sprayers are extremely useful for treating small turf areas infested with weeds. But they have to be calibrated to apply the recommended rate of a herbicide.

Most herbicides used in turf grasses control weeds without injuring the turf. But that depends on the rate applied. The rate is usually on the product label as the amount to be applied to 1 acre or 1,000 square feet.

For example, the highest recommended rate of Trimec Classic for Bermuda grass and tall fescue is 1.5 fluid ounces per 1,000 square feet.