Wednesday, September 3, 2014

Pecan weevils emerge

    After a hot and very dry month of August, a large storm spread over our area on the 1st day of September. Along with an amazing lightning display and high winds, this storm dumped 5 inches of rain on our pecan grove. The much needed moisture will help fill out pecan kernels but has also created the prefect soil conditions for pecan weevil emergence. Today we collected up to 5 weevils in a Circle trap.
    When weevils emerge from the soil they crawl and fly up into the nearest pecan tree. Once in the tree's canopy, both male and female weevils search out a nut cluster (photo above). After arriving at the nut cluster, male and female weevils will find each other and mate. Several days after mating, the female weevil will begin laying eggs inside the nut.

    It is fairly easy to tell the difference between male and female weevils. Female weevils have a much longer proboscis than their male counterparts. In the photo at left, the male weevil is the insect on the upper right. The female is located on the lower left side of the photo. Looks like these two will be doing the weevil tango before too long.
   To remind everyone that weevils can and do fly, I was also able to photograph a weevil adult preparing to take flight (photo at right). A weevil will raise its two hard wing-covers to reveal a pair of translucent, copper-colored wings. A pecan weevil may not be the best aerial acrobat, but this insect will fly from un-managed, weevil-infested, native trees into your orchard just to find a place to lay eggs. That it one reason why we have been setting up traps outside of our orchard. I don't like to be caught unaware by migrating weevils.
    We will be spraying for weevil starting Thursday Sept. 4.