|Mild weather has some pest impact |
|Posted: Tuesday, March 27, 2012 3:04 pm |
|The recent mild winter has elicited much speculation on how this will affect insect populations this spring and summer. |
For the most part, we expect the same complex of pest insects to occur this year as last.
While some insects will emerge a week or so earlier than in past years, this in itself should not be a reason for major concern. Insects in Tennessee are acclimated to our weather and up and down winter temperatures tend to be the norm.
Thus, most insects are able to successfully overwinter and emerge in the spring.
While sometimes winter weather will reduce insect populations, insects have a high reproductive potential and can increase their populations quickly when favorable conditions occur. One of the best examples is the many species of mosquitoes that overwinter in Tennessee and other states.
Mosquitoes can overwinter as eggs, larvae or adults depending on the species. In the spring and summer they need warm standing water for their aquatic immature stages to develop.
The plentiful rainfall and warm temperatures of a typical Tennessee spring bring about the numerous pools of water needed for mosquito populations to increase rapidly.
Another example is the imported fire ant, an invasive pest originally from South America.
These insects have become established in more Tennessee counties than entomologists had initially predicted. They can be insulated from cold temperatures by moving deeper into the soil.
While some years we have 75 percent or more kill of imported fire ant colonies due to cold winter weather, newly mated queens can quickly disperse and start new colonies in the spring and early summer when favorable conditions such as warm weather, rainfall, and high humidity occur.
Thus, in spite of the occasional hard winter, the number of imported fire ant colonies tends to increase over time.
Insects can be major crop pests so continue to scout crops and follow UT Extension recommendations for controlling damaging populations.
Just realize that you will probably need to start your pest scouting program a week or two earlier this spring.