Time to Check on Pecan Casebearers
Dr. Chris Sansone, AgriLife Extension entomologist at San Angelo, says “May can be a make-or-break month for pecan production, and it’s also the month pecan nut casebearers hit the crop, leaving only a short window when control measures are effective.”
He says the best control is a springtime insecticide, but timing is all-important. May 17 is the decision window set for Tom Green County – not the actual date to spray, but the predicted date for the first significant egg lay in the county. (The date would be different for Glasscock County.)
Temperature fluctuations have a strong bearing on the moths’ activity, according to Sansone. He recommends scouting the trees, and not relying on prediction dates alone. Sansone says to consider spraying when two or more eggs are found while inspecting 10 nut clusters per tree. Ideally, spray when the hatch has started and is increasing.
Sansone says two web sites developed by AgriLife Research and Extension entomologists can help producers and homeowners with the timing: http://pecankernel.tamu.edu and http://PNCforecast.tamu.edu.
Some producers who anticipate a huge crop may opt not to spray at all, but instead let the casebearers thin the nut load to preserve the health of the tree and the quality of remaining nuts.
“Confirm” and “Intrepid” are two insecticides for commercial producers. Homeowners are limited to products containing spinosad, Bacillue thuringiensis (Bt), carbaryl or malathion.
More information on the casebearer can be found in AgriLife Extension publication E-173, available at http://agrififebookstore.org. Other publications on pecan insects accessible through the site include “Managing Insect and Mite Pests of Commercial Pecans in Texas” (E-215) and “Homeowner’s Guide to Pests of Peaches, Plums and Pecans” (E-145).