Addison Blog

The official blog of Addison Pest Control

What Is Frass?

Frass is one of the most readily identifiable indicators that a pest has taken up residence on your property. The term frass is the technical term for the excrement and other refuse and leavings of insects and their larvae.

  • It is sometimes found in small piles or drifts mixed with sawdust, for example, or bits of whatever the insects are consuming or excavating.
  • It can also appear as tiny scattered pellets near nesting areas or travel routes.

Finding these deposits can be puzzling to property owners, but closer inspection usually leads to the discovery of some type of unwanted tenant.

Identifying Insects Through Frass

Observant home owners and gardeners can find insect frass both indoors and out. Many gardeners spot caterpillar frass scattered beneath a tomato plant, for example, and know that a hornworm is at work. Similarly, ladybugs seeking a warm spot indoors to overwinter will leave evidence in their wake. While many insects are fine in their natural settings in the wild, many become problematic or even destructive in domestic or commercial settings. Frass is a key way of identifying, finding and treating them.

Types of Frass To Look For

Some of our most destructive pests leave signature piles or dustings of frass. Regular inspections can often alert you to their presence:

    • Ants: While many ants are easily identified through mounds or working trails, carpenter ants present special challenges. Fourteen species of carpenter ants live in Texas. Some fly while others do not, but all tunnel through and build their colonies in wood that is moist or water-damaged. Cone-shaped piles of frass, shredded wood fragments and insect debris form beneath or near nest openings.
    • Bed Bugs: Nocturnal feeders on human blood, bed bugs will leave tiny reddish-brown frass stains in and under bedding or other places where they wait for or feed on their prey.
    • Carpenter Bees: Piles of sawdust and fan-shaped pollen-like or moldy frass stains indicate a dime-sized nest hole is somewhere above, in a piece of wood. Carpenter bee tunnels can be 8 inches or longer. They draw woodpeckers in search of the bee larvae inside and leave sites open to weather damage.
    • Carpet Beetles: Beetles can attack a wide variety of textiles, upholstered furniture, and even paper and books. They prefer dark, undisturbed areas where larvae can feed on fibrous materials undisturbed. Frass is typically made of very fine granules the color of the textile consumed.
    • Cockroaches: Cockroaches come in both the indoor variety and those that prefer the outdoors but wander inside. Indoor cockroaches are typically the smaller, darker German cockroaches. These will leave small dark droppings resembling crushed pepper around harborages—areas where they can remain concealed during the day. Outdoor intruders will leave similar pellets that are slightly larger.
    • Powder Post Beetles: These beetles and many other boring beetles lay their eggs beneath wood surfaces and often go unnoticed as the larvae consume the wood inside. They emerge as adults from small round holes that resemble gunshot. They leave fine, powdery frass that typically accumulates below the infestation site before repeating the nesting process.
    • Termites: Subterranean termites will use frass to build mud tubes or a material that looks much like fine cardboard. Dry-wood termites will expel frass through kick-out holes to leave piles of distinctive, multi-colored six-sided fecal pellets that have been cleaned from the nest.
    • Wasps and Bees: Wasps and bees tend to be clean insects that do not void in the nest. However, lots of small yellowish, sticky or liquid tubular deposits on cars, for example, or other surfaces may indicate that an active nest is nearby.

What To Do If You Find Insect Frass

Alone or mixed with other insect refuse, frass—its location, composition and volume—can provide vital information about an insect pest’s identification and the most appropriate way of treating it. Effective approaches vary widely. What works on one type of ant, bee, beetle or cockroach may not work on another type.

If you find frass and suspect that you have an insect issue, contact Addison Pest Control and let our professionals help. We offer the safest, newest methods of controlling and treating insects and other pests as well as prevention, decontamination and restoration services for your home. We can treat your issue and help you ensure that it won't happen again.

We proudly serve McKinney, Texas as well as many other surrounding towns. Check out our service area to see if we can help out your home or business!

Rate this blog entry:
Surprising Facts About Ants
What Type of Climate Do Termites Live In?