Residents in the nearby four-parish area could see a second, more determined generation of walnut caterpillars this month, just as walnut and pecan trees previously attacked make their recovery.

LSU AgCenter agent Keith Hawkins said the pests’ second generation could prove to be more difficult to combat than the first generation and could ultimately kill trees that cannot fend them off.

“The second-generation female moth will lay eggs on the new foliage and will make it extremely difficult for a homeowner to be able to treat a fully mature tree,” Hawkins said.

While there are some insecticides on the market that could provide a tree with the ability to fend off another infestation, Baton Rouge LSU entomologist Dennis Ring warned homeowners to be cautious when treating their backyard trees.

“We advise caution to homeowners because you don’t want to eat any nuts that are produced from a tree that has been treated with certain insecticides on the market, nor do we really recommend a homeowner try to cast insecticide onto a 50-foot tree and it end up covering their neighbor’s home,” Ring said.

According to Ring, the walnut caterpillars have “outbreak biology,” meaning they appear suddenly and then subside for lengthy periods of time.

The last outbreak was in the 1970s in central and east Texas. He said it’s unclear what has made them reappear, but that the lack of a lengthy winter last year could be the culprit.

Ring said the second generation of caterpillars typically emerges within 32 to 40 days of the previous generation.

Reports of outbreaks appear to be localized to Beauregard, Vernon, Allen and Calcasieu parishes — which is welcome news for Rapides Parish pecan farm Rosalie Pecans.

Stephen Norman said he couldn’t recall a major infestation plaguing his farm in recent years, and that so far projections for his year’s season remain strong.

“The projection for this year is around 16 million pounds, which for us will be a very good season,” he said.