Sacramento Digs Gardening Article
Your resource for Sacramento-area gardening news, tips and events

Articles Recipe Index Keyword Index Calendar Twitter Facebook Instagram About Us Contact Us

Catch codling moths early

Sacramento Digs Gardening
BY Debbie Arrington PUBLISHED JUL 20, 2020

Look for the telltale frass, as seen on this Granny Smith. Remove that apple and eliminate a codling moth larvae, too. (Photo: Debbie Arrington)

This pest attacks apples, pears, walnuts

If you've ever bitten into an apple and found a little pink worm, you've encountered codling moths.
That worm is the moth's very hungry larva. It tunnels through the apple's flesh, creating ugly brown scars.

Eventually, the apple -- or the larva -- falls to the ground, where the moth continues its life cycle.

Codling moths love apples but also attack pears and English walnuts. Their damage is becoming very visible now.

Notice any odd holes on the side of baby apples? The holes may be topped by little brown piles. That's frass, reddish-brown droppings from the larva as it bores into the fruit.

If left uncontrolled, codling moths can infest 20% to 90% of a tree's fruit. Late-developing varieties tend to be hardest hit.

Codling moths can have three or four generations a year. In Sacramento, we're likely on generation 2. According to the UC Cooperative Extension master gardeners, codling moths overwinter as full-grown larvae in silky cocoons wedged under the tree's bark. The adult moths emerge in April. They start mating when temperatures reach 62 degrees at sunset, the only time they're active.

That makes these moths hard to trap or fight with pesticides.

The best ways to limit codling moth damage are sanitation and exclusion, say the master gardeners.
Sanitation means picking up and discarding fallen fruit. Check your tree every two weeks and look at the developing fruit. Remove and destroy any infested fruit showing frass holes; the larvae is still inside. That will cut down the next generation. That thinning has the added benefit of encouraging remaining fruit to grow bigger.

Bagging the baby fruit can exclude the moths and larvae. It's tedious and nearly impossible with a large tree but very effective especially on smaller trees. Master gardeners suggest using paper lunch bags. Cotton bags with string ties also work.

Trapping can reduce populations on isolated trees, but isn't a reliable way to reduce damage, say the master gardeners.

Because codling moths can get around, enlist neighbors with apple, pear or walnut trees to fight moths, too. That can help reduce their toll and increase everyone's harvest.

For more information including bagging instructions: https://ipm.ucanr.edu/PMG/PESTNOTES/pn7412.html .

Comments

0 comments have been posted.

GENERAL GARDENING

An article about gardening.

Keywords:

apples gardening Sacramento integrated pest management pests codling moth orchard fruit home orchard insects

Newsletter Subscription

Sacramento Digs Gardening to your inbox.

Taste Spring! E-cookbook

Find our spring recipes here!

Local News

Thanks to our sponsor!

Sites We Like

Garden Checklist for week of May 5

Survey your garden after the May 4 rainstorm. Heavy rain and gusty winds can break the neck of large flowers such as roses. Also:

* Keep an eye on new transplants or seedlings; they could take a pounding from the rain.

* Watch out for powdery mildew. Warmth following moist conditions can cause this fungal disease to “bloom,” too. If you see a leaf that looks like it’s dusted with powdered sugar, snip it off.

* After the storm, start setting out tomato transplants, but wait on the peppers and eggplants (they want warmer nights). Pinch off any flowers on new transplants to make them concentrate on establishing roots instead of setting premature fruit.

* Trim dead flowers but not leaves from spring-flowering bulbs such as daffodils and tulips. Those leaves gather energy to create next year's flowers. Also, give the bulbs a fertilizer boost after bloom.

* Pinch chrysanthemums back to 12 inches for fall flowers. Cut old stems to the ground.

* Mulch around plants to conserve moisture and control weeds.

* From seed, plant beans, beets, cantaloupes, carrots, corn, cucumbers, melons, pumpkins, radishes and squash.

* Plant onion sets.

* In the flower garden, plant seeds for asters, cosmos, celosia, marigolds, salvia, sunflowers and zinnias. Transplant petunias, zinnias, geraniums and other summer bloomers.

* Plant perennials and dahlia tubers for summer bloom.

* Don’t wait; plant summer bulbs, such as gladiolus and tuberous begonias.

* Harvest cabbage, lettuce, peas and green onions.

Taste Summer! E-cookbook

Find our summer recipes here!

Taste Fall! E-cookbook

Find our fall recipes here!

Taste Winter! E-cookbook

Find our winter recipes here!