Christmas tree growers go unnoticed 11 months of the year.
But like other farmers, they work hard fighting diseases and
insect
pests year-round. Thanks to some on-farm research, they may not
have to work so hard fighting one major pest.

Bob Slaughter and his father, Bill, operate The Old Barn
Christmas
Tree Farm, an 11-acre farm in Spalding County, Ga. Slaughter also
works full-time as a research coordinator for the University of
Georgia College of Agricultural and Environmental Sciences’
Entomology
Department.

Seeing UGA researchers tackle Georgia’s pest problems every
day prompted Slaughter to fight back against the Nantucket pine
tip moths that were feasting on his trees and his profits.

Eating Away At The Tips

The moth is a major pest of Virginia pines grown for the
Christmas
tree market. Its larvae enter the tip of the tree branches, where
they feed on the shoots and damage the tips. Infested twigs turn
brown and die, resulting in poor tree shape and growth.

The adults are small, gray moths with brick-red to brownish
patches on their wings. Fully grown larvae are orange-brown. The
moths attack loblolly, shortleaf, Virginia and other pines
except white
pines.

“Tip moths are the most serious insect pests attacking
Virginia pine Christmas trees in Georgia,” Slaughter said.
“They result in added expense, input, time and our exposure
to pesticides.”

In a three-year study, Slaughter coordinated tree shearing
and insecticide applications to find the most effective way to
control the pest.

He partnered with fellow tree grower Tom Akin of Circle A Farm
in Barnesville, Ga. The study was duplicated on both the
Slaughters’
and Akins’ farms to enhance the data collection.

Cutting Instead of
Spraying

“My idea was to control the tip moths in three-year and
older trees with normal shearing practices,” Slaughter said.
“This mechanical control would eliminate the moth-infested
tips before they could damage or deform the tree. And it would
eliminate or reduce the need for insecticide
applications.”

Slaughter and Akin performed their study on three-year-old
Virginia pines. Typically, growers apply insecticides six or more
times a year to fight the three generations of moths that feed
on trees in Georgia’s piedmont and mountain regions. Once trees
are 3 years old, growers shear them twice a year in the spring
and late summer.

“Our study looked at whether the shearing can be used
as a control method by removing the infested tree tips,”
Slaughter said. “We sheared the trees twice during the
season.
We also treated them with five insecticide applications
coinciding
with the tip moth generations.”

The study shows that shearing alone effectively controlled
the first and second generations of the moths. “But the
second
shearing didn’t give satisfactory control for the third
generation,”
said Slaughter. “But spraying at the recommended times did
control the third generation and any overlapping generations for
the rest of the season.”

Slaughter plans to share his research findings with the
Georgia
Christmas Tree Growers Association.

“Using this method, growers only need to apply pesticides
twice a season, not the typical six or more times,” he said.
“This is a significant reduction.”