Scout and Use Thresholds for Cotton Insects

 

 

“Producers in Georgia have the opportunity to fully utilize an integrated approach to pest management (IPM) utilizing a variety of control tactics rather than relying solely on one method of control such as insecticide use.  Scouting and the use of thresholds, cultural practices, variety selection, biological control, and insecticides used on an as-needed basis are the building blocks of an IPM program.  Pests are managed so that economic damage and harmful environmental side effects are minimized while maximizing profits.  In most IPM programs insecticide use decreases resulting in lower production costs, delayed resistance problems, and improved competitiveness and profitability.  A successful and economical cotton pest management program mandates the use of this multi-tactical or IPM approach to insect control.

 

The most common insect requiring insecticide treatment at this time is stink bugs.  Stink bug numbers are up compared with previous years and most fields will require insecticidal control.  Scouting will allow growers to properly time needed applications or maybe even avoid having to treat.  When treating stink bugs be aware of other pests in the field.  The presence of corn earworm, whiteflies, and/or mites should influence insecticide selection when targeting stink bugs.  Granted the primary objective is to control the problem pest (i.e. stink bugs) but we must also consider other pests while doing so.  Avoid products known to flare the previous mentioned pests if present.

 

Corn earworm escapes in Bt cotton are very spotty and as a whole we would say infestations are generally low.  However, there are some fields which have exceeded threshold and required treatment.  None of the Bt technologies are immune to corn earworm damage.  Differences in performance do exists.  Three-gene Bt cottons provide the greatest control of corn earworm followed by the two-gene Bt cottons Bollgard II and TwinLink, and then WideStrike.

 

Agents, scouts, consultants, and growers are monitoring silverleaf whiteflies closely.  We continue to see whitefly populations build, especially in areas historically infested by whiteflies.  Hot and dry conditons favor whitefly development.  There are some hot spots which were treated for whiteflies in recent days.  It is extremely important that whitefly insecticides are applied in a timely manner when the threshold is met.  Conserve beneficial insects when possible, only spray other pests if thresholds are needed based on scouting.”

 

 

As Dr. Roberts mentioned, we have been monitoring silverleaf whiteflies (SLWF) in the county.  Whiteflies are now present in many fields in the county, but only a few fields have reached the threshold for treatment.  Let’s keep a close watch on cotton fields, especially some of the later planted cotton.