Light Brown Apple Moth: What to Know

Medically Reviewed by Poonam Sachdev on January 12, 2023
5 min read

When you imagine an invasive species, you might picture termites, ants, or spiders — not a cute, small moth. However, the light brown apple moth can cause severe damage to agriculture and disrupt nationwide food distribution networks

Learn more about this common pest and determine the best ways to stop light brown apple moths from spreading.

The light brown apple moth is a common “leafroller” pest that damages plants by living on, eating, and laying eggs on their leaves. Leafroller species are notorious for hiding in crops that humans use — like fruit trees, vegetable vines, and ornamental shrubs — and destroying the foliage and fruit throughout their life cycle. These insects aren't the same as pantry moths, but they're a similar size and color.

Light brown apple moth physical characteristics. Light brown apple moth larvae (the caterpillar stage) are light green with brownish heads. They’re only about half an inch long. This type of moth likes to spend time on the undersides of leaves, making it difficult to spot them.

As their name suggests, mature apple moths are yellowish-brown with flecks of white on the ends of their wings. When their wings are fully spread, you'll notice that the bottom portion of their hindwings is closer to a light cream color than brown. Females have brown spots at the base of each forewing, while males don't have these spots.

Light brown apple moth life cycle. Unlike other types of pests that die out during the colder months, light brown apple moths don't have a dedicated dormant period. Adult females lay eggs on fruits or leaf surfaces, usually up to 50 eggs at a time. When the eggs hatch, the larvae feed on the host plant and grow into pupae. 

The larvae develop a hard, brown chrysalis and construct leaf rolls — a special type of cocoon that they attach to the underside of leaves — as they feed on the leaf or nearby fruit and wait to become adults. Because these moths don't hibernate or go dormant, they can produce three to five generations of light brown apple moths per year.

The light brown apple moth, with the scientific name Epiphyas postvittana, is very similar to other leafroller moths in the Tortricidae family native to Australia. Tortricidae larvae feed on plants, stems, and even fruits of their host plants. The light brown apple moth larvae look like the larvae of other leafrollers, so they're tough to distinguish from other leafroller species. 

Light brown apple moths have spread throughout several continents and regions. Learn more about where to find this pest and how to locate its eggs and larvae.

Around the world. Though light brown apple moths are native to Australia, they’re now found in several countries, including Ireland, New Zealand, and the United States (including Hawaii). In the United States, they cause the most damage on the west coast as they’re sometimes imported with shipments of fruit. 

Apple moths thrive in the northern part of California — especially in the San Francisco Bay Area. This region has high humidity, cool summers, and moderate winters.

In your yard. Light brown apple moths are leafrollers, which means they lay eggs and make their homes on leaves that they “roll” together. The larvae also produce silk-like strings to tie their leaf into a rolled-up shape. This protective covering allows the eggs to withstand harsh weather as they wait to hatch. 

As the larvae grow, they might eat the fruit of the tree and its leaves. This makes the light brown apple moth an invasive species that can destroy the appearance of a tree and the fruit it produces.

On close inspection, you’ll see that the leaves of an infested tree or bush look torn or jagged around the edges. You might also observe trees completely defoliated or destroyed by these pests. Fruit might fall off the tree prematurely. 

If you suspect an infestation but aren't sure if the culprit is the light brown apple moth, it’s a good idea to call a pest control expert for help.

Light brown apple moth damage is caused by these moths doing what they do best: rolling leaves, eating foliage and fruit, and laying eggs. They’ll leave your home alone, but they can cause huge damage to a small home orchard or even a crop of fruit trees.

The conditions that create moth problems are usually climate-based. These moths don't enjoy extremely hot or cold temperatures, but they can exist in nearly any temperate climate, including dry areas. They do best in humid, cool weather. When an area with the ideal climate includes the moths’ preferred trees and shrubs, you have the potential for infestation.

Light brown apple moths won’t hurt you or your pets, but they can do major damage to trees, fruit, and ornamental shrubs. It’s best to remove them whenever possible with the safest method available to your area.

It’s difficult to completely eliminate an invasive moth population. Consider the following suggestions and combine at-home prevention methods with professional light brown apple moth control:

  • Prevention: If you’re planting fruit trees in an area where you know light brown apple moths exist, do your best to clean and mow the area before planting anything new. Removing parts of old plants (including stems) can help get rid of leftover moth eggs from the last season.
  • Predators: If you live or work in an area with a documented light brown apple moth problem, you might consider releasing natural predators that feed on the local leafroller population. Researchers discovered that a few species of Trichogramma wasps, which are tiny wasps that like eating insect eggs and larvae, could be a good natural defense instead of using sprays and pesticides.
  • Organic sprays: Spraying with Bacillus thuringiensis and other pest-control treatments approved for organic crops can be a non-toxic way to prevent light brown apple moth populations from surging in the upcoming growing season. But these sprays might not keep an already out-of-control population in check.
  • Pesticides: Pesticides should ideally be a last resort as many of them pose health problems for people, animals, and local beneficial insects.

Attracting light brown apple moths with synthetic pheromones isn’t a reliable treatment method. You can set these “traps” to monitor an invasive species or test the area for a potential infestation, but it’s not possible to attract all of the moths this way.

Adult female light brown apple moths can produce up to 1,500 eggs in their lifetime. If you suspect an apple moth infestation, don’t wait until you see dozens or hundreds of pests to ask for help. Get in touch with a local pest control professional to determine your next steps.