John Richburg, Ph.D.
Field Scientist R&D
Coastal Crops – East, Dow AgroSciences
Headland, Ala.
Uncharacteristic to the Southeast, cotton growers in Alabama, Georgia and the Florida Panhandle have experienced isolated hot spots of tarnished plant bugs, prompting growers to be diligent in scouting fields for the presence of this potentially devastating pest.
The incidence of plant bug hot spots bears watching to determine if this is just a blip or the start of a concerning trend. Growers should pay serious attention since the pest has the potential to sneak up and take a big bite out of yields. Be diligent about scouting, especially early on during square retention.
Controlling Plant Bugs
When scouting for plant bugs early in the season, sweep nets are used most commonly because adults are mobile. Later, when cotton is nearing the bloom stage, scouting for plant bug nymphs is most effective using a drop cloth.
Treatment thresholds vary by state, but the general rule is eight bugs per 100 sweeps for early season, and three plant bugs per five feet of row when scouting for adults and nymphs using a drop cloth later in the season. Transform® WG insecticide has proven extremely effective in controlling tarnished plant bugs in cotton at the rate of 1.5 oz./A.
Sugarcane Aphids On The Move
A growing concern for sorghum growers is the northeasterly migration of sugarcane aphids. The pest overwintered much farther north and east this past year and was discovered earlier than anticipated so growers should be diligent about scouting early and often. Sorghum fields should be checked every three to four days as aphid populations can proliferate very quickly.
More definitive treatment thresholds for sugarcane aphids are currently being established but as a general rule, treatment is recommended when 50 to 100 aphids are present per plant and 20 percent of plants are infested.
Transform was the only proven control option for controlling sugarcane aphid in 2014, and it has received Section 18 emergency exemption in the following states: Alabama, Arkansas, Georgia, Kansas, Louisiana, Mississippi, Missouri, Oklahoma, South Carolina, Tennessee and Texas.
Sorghum growers have reported excellent coverage of the sugarcane aphid at the rate of 1.0 oz./A.