As cotton seed begins to emerge around the county, growers hopefully have already put some thoughts into their thrips management strategy for 2015. A recent Growing Georgia story discussed thrips management in 2015 cotton.
Here are some tips from Dr. Phillip Roberts, UGA Extension Entomologist, that can be found in that story:
- Know that thrips are predictable. “Some years we have high populations; some years we have low populations,” said Roberts, but the number doesn’t necessarily indicate how much damage they do. Instead, thrips are worst in years when nature provides them the longest time to get at vulnerable plants. For example, thrips do the most damage when cool weather or other plant stressors slows growth of cotton seedlings.
- Understand your risk of economic injury. Planting date makes a big difference. Thrips populations are highest and can do the most harm in early cotton, farmers who plant in April or early May should consider the cost of a pesticide treatment when they run the budget. Even when using pretreated seed, factor in the cost of a later foliar treatment for early planted cotton. Tillage also can impact the risk of thrips. Reduced tillage systems tend to have fewer thrips compared with conventionally tilled land.
- Thrips control is most important in the smallest plants. While thrips can attack and injure cotton plants upto the 4-leaf stage, the threat of yield loss shrinks as the plant gets larger. “Every time the plant puts on a new leaf, it becomes less susceptible to thrips,” Roberts said. Typically, a producer will face his first decision to spray about two weeks after planting, when cotton hits the one-leaf stage.
- Be most attentive when you aren’t seeing rapid growth in the plants.“You can’t control the weather, and thrips do the most injury in years that have a cool, wet spring,” Roberts said. Years like 2015 – with relatively cool, wet weather – can draw out the amount of time that the plant is susceptible and give thrips more opportunity to get at a crop. “Anything you can do to encourage healthy, rapid growth can help a plant tolerate thrips,” Roberts said.
You can find the whole story from Growing Georgia at the following link: http://growinggeorgia.com/features/2015/04/fighting-thrips-all-about-timing/?utm_source=Growing+Georgia&utm_campaign=7fb9e87b29-growinggeorgia-daily_newsletter&utm_medium=email&utm_term=0_4643f190f7-7fb9e87b29-296616809
If you have any questions about managing thrips in cotton, contact your local county agent for more information.