Small, soft bodied, yellow insects feeding on undersides of leaflets, producing honeydew
YELLOW APHIDS (yellow pecan aphid or blackmargined aphid)

Small, soft-bodied, dull-black sucking insects producing yellow blotches on foliage
BLACK PECAN APHID

Tiny, greenish, eight-legged arthropods congregating on undersides of leaflets near mid-rib; often forming very light webs.  Difficult to see without magnification.  Leaves may appear scorched
MITES

Linear, whitish to tan, winding mines about 2 mm wide just beneath upper surface of leaflets; or irregular blotch mines as large as 15 - 15 mm in diameter
LEAFMINER

Dark green caterpillars in small. Gray case feeding on unfolding buds and leaves in spring,          or feeding on undersides of leaves from May to November
PECAN LEAF CASEBEARER

Hard swellings or galls on leaflets, leaf stems, twigs or terminals
PHYLLOXERAS

Olive-gray to green caterpillars tunneling in shots in early spring
PECAN NUT CASEBEARER

Masses of frothy white foam enclosing tiny greenish insect on terminals and at bases of nut         clusters in spring and summer
SPITTLEBUG

White, legless grubs, 5 - 7 mm long, tunneling in pith of newly formed shoots in spring.  Shoots may have irregular holes in their sides following larval emergence
HICKORY SHOOT CURCULIO

Small. pale green caterpillar with black pronotum feeding in buds and unfolding foliage of terminals and axils, primarily on young trees
PECAN BUD MOTH

Hairy, pale yellow, spotted caterpillars up to 31 - 32 mm long feeding in large webs, often encasing entire branches
FALL WEBWORM

Large colonies of black caterpillars with long soft hairs feeding in colonies and stripping leaves. no webs
WALNUT CATERPILLAR

Light green caterpillar-like larvae with fleshy prolegs on second abdominal segment eating          roundish, regular-shaped holes in leaflets in early spring.  Mid-ribs and veins of leaflets left intact
SAWFLY

Brown beetles feeding on foliage at night, usually found hidden in protected places in daytime
MAY BEETLES

Green beetles feeding on foliage at night
GREEN JUNE BEETLES

B.  Insects Attacking the Nuts

Olive-gray to green caterpillars up to 14 mm long feeding on buds or in young shoots in early spring. Later in spring, feeding in young nuts, usually entering near stem end. Infested nuts often held together by silken threads containing frass pellets
PECAN NUT CASEBEARER

Whitish caterpillars up to 10 mm long feeding in developing nuts, causing them to drop; or tunneling in shucks of older nuts
HICKORY SHUCKWORM

Small, gray to brown snout beetle feeding and ovipositing in developing nuts; white legless grubs feeding inside young nuts prior to shell hardening, causing nuts to drop
HICKORY NUT CURCULIO

Light brown to grayish weevil, up to 13 - 14 mm long, with slender snout at least 2 as long as body, feeding on nuts prior to shell hardening, causing nut drop; creamy white legless grubs with brown heads feeding in nuts after shell hardening, or nuts showing small round exit holes about 3 to 4 mm in diameter
PECAN WEEVIL

Light green to brown shield-shaped bugs, up to 12 - 15 mm in length, feeding on nuts in late summer.  Causing black pit and kernel spot
STINK BUGS AND PLANT BUGS

C.  Insects Attacking Limbs, Trunks, and Twigs

Long-horned beetles girdling twigs and limbs in late summer and fall
PECAN TWIG GIRDLER

Shot-like holes in trunks and dying limbs
SHOT HOLE BORER, PIN-HOLE BORERS

Round holes about the size of a pencil in the trunk or larger branches, characterized by a pile of reddish frass pellets, often mixed with sawdust, beneath the hole
PECAN CARPENTERWORM