Forest
Health Protection, Southern Region
WALKINGSTICK,
Diapheromerafemorata (Say)
Importance. - The walkingstick attacks oaks and other hardwoods. In the South, severe outbreaks have only
occurred in the Ouachita Mountains of Arkansas and Oklahoma. Branches are killed or die back in heavily defoliated stands, but
continuous defoliation for several years can result in mortality. The insects create a nuisance in high use areas such as parks and
recreation sites.
Identifying the Insect. - Nymphs and adults are slender and have long thin legs and antennae. While motionless,
they closely resemble their host. Adults are about 2 1/2 to 3 inches (62 to 76 mm) long, and their body color varies from brown to green to
multicolors of gray, green, and red.
Adult walkingstick - note how it blends with foliage. (Click for detail. JPG 24K)
Identifying the Injury. - The entire leaf blade, except the base of the stout veins, is eaten. During heavy
outbreaks, large stands are often completely denuded. Trees may be defoliated twice during the same season. Because the
walkingstick does not fly, infestations are often localized and spread only a few hundred yards during the season.
Patches of heavy defoliation. (Click for detail. JPG 42K)
Biology. - Overwintering eggs in leaf litter hatch in May and June. Nymphs become adults during the summer
and fall. Females deposit up to 150 eggs, which are randomly dropped to the forest floor. There is one generation per year in the
South, while 2 years are required farther North.
Control. - Natural enemies, particularly birds, are often effective. Chemical control is occasionally warranted
in high use areas.
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