What's Eating My Apple Tree?
Apple trees host a whole economy of freeloaders — some ruin fruit from inside, some work the leaves, and a few gnaw the tree itself. Match the evidence below before you spray anything.
The usual suspects
Codling moth
The signs: The proverbial worm in the apple: a hole near the blossom end or side plugged with crumbly brown frass, and a tunnel to the core.
What it looks like: Pinkish-white caterpillar with a brown head; the parent moth flies at dusk starting around petal fall.
What to do: Bag prized fruit with nylon footies or paper bags after June drop, pick up every dropped apple weekly, and hang pheromone traps to time controls if you use them.
Apple maggot
The signs: Dimpled, distorted fruit surface with winding brown trails all through the flesh — discovered at the first bite.
What it looks like: Larvae of a small fly that lays into fruit midsummer; the flesh breaks down along the tunnels.
What to do: Hang red sticky-sphere traps in the canopy from early summer, collect drops religiously, and don't compost infested fruit.
Plum curculio
The signs: Small crescent-moon scars on young fruit that grow into corky knots; heavy strikes drop fruit in June.
What it looks like: A small warty snout weevil that works at petal fall, hitting all tree fruit.
What to do: Spread a tarp and knock the limbs sharply each morning for two weeks after petal fall — the weevils drop and can be collected. Pick up all June drops.
Tent caterpillars and fall webworm
The signs: Silk tents in branch crotches (spring, tent caterpillars) or webs enclosing branch tips (late summer, webworm), with leaves stripped around them.
What it looks like: Colonies of hairy caterpillars inside the silk.
What to do: Pull nests out by hand or with a pole on a cool morning and drop into soapy water — no burning, which hurts the tree worse than the caterpillars do.
Aphids
The signs: New shoot tips curled tight and sticky; rosy aphids also pucker and redden leaves and stunt fruit clusters.
What it looks like: Colonies inside the curled leaves, ant-attended.
What to do: Prune out badly curled tips, blast what you can reach, and let lady beetles work — mature trees tolerate aphids well.
Deer, rabbits, and voles
The signs: Browsed twigs and buds head-high (deer), bark gnawed clean around the trunk base in winter (rabbits and voles) — a full girdle can kill the tree.
What it looks like: Paired incisor marks low on the trunk; ragged browse above.
What to do: Hardware-cloth trunk guards from below soil line to two feet, pulled mulch, and fencing for young trees — this is the damage that's fatal, so guard first.
When it's not a pest at all
Olive-brown velvety leaf spots and cracked corky fruit lesions are apple scab, the East's defining apple disease. Orange spots with tiny tube structures are cedar-apple rust, courtesy of nearby junipers. Both are fungi — no appetite involved.
Or just point your phone at it
Snap a photo of the leaf, the bug, or the droppings, and Harold — the advisor built into Homestead Paradise — names what he sees, tells you friend or foe, and what he'd do next. Honest when he's unsure, and careful where it counts.
Put Harold's Eyes on it — free 14-day trial