Farm Talk

October 23, 2012

Pecan field day examines challenges faced by growers

by Doug Toburen
CNHI

— When thinking of crops grown in Kansas most people are quick to recognize wheat, soybeans, corn and some sorghum.

However, one crop that continues to be of interest to a number of producers is none other than pecans.

According to Kansas State University data, Kansas contributes approximately one percent of the total U.S. pecan production. There are an estimated 8,500 acres of pecans in Kansas, mostly concentrated in the southeastern corner of the state.

At the recent K-State Pecan Field Day held at the Pecan Experiment Field near Chetopa, Kansas, a number of growers and enthusiasts were on hand to hear the latest information about the 2012 crop.

Like with any crop, pecan growers have to deal with the drought as well as insect and pest control.

According to Bill Reid, K-State Extension pecan specialist, after the drought last year, and going through another this year, he wasn’t sure how the crop would do.

“We actually had a very heavy nut set this year even with the drought,” Reid explained. “Our native pecan trees have an average cluster size of 3.8 which means we may be looking at a record-breaking crop in 2012.”

Although this year may be a record crop, Reid told those in attendance at the field day that it was still a year filled with challenges.

One challenge pecan growers face on an annual basis is dealing with the pecan nut casebearer.

“This is the primary nut feeding insect that pecan producers must monitor closely,” he explained.

According to him, in low production years casebearer larvae can completely wipe out a nut crop. However, in years that trees produce an excessive crop, casebearer feeding can work as a beneficial nut thinning agent.

The casebearer can be controlled by spraying, yet Reid advises growers to follow some basic rules when it comes to spraying or not spraying.

“When it comes to determining whether or not to spray we start by counting the number of nuts in a cluster on at least 300 nut bearing terminals,” he said. “If the average cluster size is 2.9 we have determined that spraying for casebearer is not cost effective and in fact nut casebearer may act as a beneficial thinning agent.”

With an average nut cluster this year of 3.8 Reid made the decision not to spray anything for casebearer.

The important part about making the decision of whether or not to spray for casebearer, according to Reid, is for growers to get out in their groves and see what is happening.

The nut specialist was quick to remind visitors to think long-term, saying an excessive crop this year may mean nothing next year.

Moving from casebearer issues to the pecan weevil, Reid said this was a perfect year to trap due to limited rainfall.

“Weevils don’t emerge from the ground until it rains and this year it didn’t rain much,” he explained. “When it did rain the weevils emerged and we caught a lot of them in the traps.”

Reid recommended spraying for pecan weevil as soon as they emerge.

“We sprayed our orchard with Sevin XLR insecticide in order to stop the female weevil from boring through the shuck and shell to lay her eggs,” he said. “In order to control pecan weevil you must prevent female weevils from laying eggs.”

One other insect Reid continues to watch for in pecan groves is stink bugs.

“During the water stage of nut development pecans seem to be attractive to stink bugs,” he said. “Stink bug feeding can cause nut drop and tends to leave a black spot on the surface of the kernel.”

As visitors moved through the pecan grove Reid mentioned a couple other varmints that are particularly harmful to pecans—squirrels and crows.

According to him, this year squirrels were starting to feed on pecans in June.

“I’ve been told a single fox squirrel can cause 200 pounds of pecan losses in a single year,” Reid said. “As soon as the nuts enter the dough stage in August squirrels begin cutting nut clusters off trees and eating the entire pecan.”

Reid and his staff have had good luck trapping squirrels this year helping to eliminate the damage they can do to the crop.

“We use #110 conibear traps mounted on small shelves above deer height on the trees,” he said. “We use pecans for bait, but be sure to glue it on or the woodpeckers will take them.”

According to Reid, some 40 squirrels were caught this year in the K-State research grove.

“The key to catching them is to start early, around June 1. Once the pecans get in the dough stage you don’t catch any, they bypass the trap and head for the nuts,”he said.

Matt Smith, USDA wildlife specialist from Manhattan, Kan., wrapped up the varmint discussion by discussing a new method for controlling crows in pecan groves.

“We want to be able to ensure a good pecan harvest in Kansas by ridding groves of crows,” Smith said.

Over the years growers have used such methods as calling and shooting and propane cannons to help control crows.

Smith said the USDA introduced a new toxicant crow controlling method to those on hand and explained the benefits of using it.

“USDA has developed DRC 1339 which is an avicide that is highly toxic to blackbirds,” he said.

According to Smith, growers can apply this to corn and place on a stand out of reach of deer and turkeys.

“Once the crows ingest the corn it causes irreversible kidney and heart damage with death occurring in one to three days,” he explained. “The toxicant is actually excreted after it is ingested so it won’t harm any animal that may eat the dead crows.”

Smith concluded by saying the only drawback to this system is that there is no funding due to USDA budget cuts.£