Leaf Feeders

Miscellaneous Pests

Fruit tree leaf roller	Orange striped oak worm
Red humped caterpillar	Oblique banded leaf roller
Spiny elm caterpillar

Tent Catapillars

Eastern tent caterpillar solid stripe down back	Eastern tent caterpillar defoliation and egg mass
Eastern tent caterpillar tent on tree

Control

The pests shown to this point are rarely controlled - if they are it is generally only in the urban / suburban setting and then only when it involves a high value tree or trees.

Forest tent caterpillar keyhole pattern down back	Forest tent caterpillars
Aerial view of forest tent caterpillar damage	Forest tent caterpillar caused defoliation
Looking up into forest tent caterpillar damaged crowns

Control

In some cases control of forest tent caterpillar is done to protect a forested area from repeated defoliation by this pest. Control is generally by insecticidal spray or by application of a biological control agent (B.t.)

Forest tent caterpillar killed by Bacillus thuringiensis

Gypsy Moth

Male gypsy moth Gypsy moth caterpillar

Female gypsy moths Gypsy moth larvae at “tree band”

Control

Significant control efforts being made. Pesticidal treatments, biological treatments, and pheromone disruption treatments are available. More later when we talk about environmental impact statements.

Sawflies

Sawfly eggs in pine needle	Adult sawfly on pine needle
Red-headed pine sawfly larvae	Sawfly damage to trees

Control

Seldom controlled in the field - but chemical treatments are available should high value loss be a probable result of an infestation.

Texas Leaf Cutting Ant

Texas leaf-cutting ant	Texas leaf-cutting ant (Town ant) town
Pine seedling 1/2 hour after Texas leaf-cutting ant attack	Entry mounds to town ant towns

Control

Methyl bromide fumigation of the town is the only current recommendation. This is a difficult and dangerous process. [Both the logistics of getting to the middle of the town which can collapse due to the operator’s weight - and the dangerous nature of the chemical involved].

Gall Causing Insects

Cottonwood petiole gall caused by aphids	Maple bladder gall - mite caused
Hackberry nipple gall - psyllid caused

Control

By the time the galls appear the damage to the existing leaves (or stems) has been done. Manual controls are the only recommended controls here - in urban / suburban settings rake and burn fallen leaves.

Sucking Insects

Balsam Woolly Adelgid on Fraiser Fir

Balsam Woolly Adelgid on Fraiser Fir

Control

Hemlock Woolly Adelgid on Eastern Hemlock

Hemlock Woolly Adelgid on Eastern Hemlock

Control

Borers

Nantucket pine tip moth - newly emerged adult	Tip moth caused terminal crook
Stand showing tip moth damage	Tip moth larva in terminal leader

Control

Chemical control is sometimes used for tip moth control - results are variable as it is difficult, however, to deliver a chemical into the xylem where the larvae feed - systemic insecticides have the best effect with this pest.

Twig girdler damage	Breakage of cottonwood stem at girdler damage
Cotonwood root borer Root borer larvae in root	Cottonwood root borer heading for the root Pine sawyer larva

Control

Girdlers and root borers are seldom controlled.

Cambium Feeders

Southern pine beetle adult
	Aerial photo of a small SPB spot expanding right to left
Aerial view of a large SPB spot	SPB adult compared to a grain of rice
Early attack - pheromones in low concentration pheromone acts as an attractant	SPB aggregate in response to pheromones
Later attack - pheromones in high concentration around heavily attacked trees - repellant action	Pitch tube formed at point of entry of adult
SPB pitch tubes compared to popcorn	Cambium “engraved” by SPB
SPB egg	SPB spot growth
SPB control options	Salvage
Cut-and-leave study plot	Operational cut-and-leave plot
Chemical control	Chemical control - Insecticide treatment of infested logs
Old SPB spot	Pales Weevil
Pales weevils on pine seedling
Weevil damage in young plantation	Weevil larva in a chip cocoon
Chip cocoons on wood (under bark)

Control

The best and most effective control here is to avoid planting sites harvested after the previous mid-summer. You do have chemical options available but they are not cost effective compared to the silvicultural option

Silvicultural control causes the birth of larvae to be poorly synchronized with the availability of fresh young seedlings.

	Fiery hunter - a ground beetle
Lace Wing larva	Assassin bug
Parasitic wasp (a Chalcoid)	Parasitic wasp (a Chalcoid)

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