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What Is Frass, and How Can I Identify It?

frass on a green leaf

When it comes to preventing and mitigating pest problems, it's critical to understand the symptoms. Infestations take many forms and involve many insect species. Fortunately, most of these issues have their own telltale hallmarks.

The presence of frass is a good indicator that your home or commercial space has become a paradise for some unwelcome pest. Here's what it is and how to keep your eyes peeled.

The Basics of Frass

Frass is a catch-all term that refers to the biological waste that insects leave behind as a natural byproduct of their metabolic activities. In other words, it's the solid excrement that they deposit in their trail as they consume materials like plants, wood, human food, blood, and other insects.

Why does insect poop need its own special name?

Due to the way insects process food, frass is significantly different from other forms of animal waste. For instance, insects like cockroaches, beetles, and ants may seem messy to us humans, but they actually remove their frass from their nests to keep their homes as sanitary as possible.

In some termite species, young insects eat the frass left behind by adults. This habit lets them acquire the vital gut bacteria that they need to break down tough wood. The process is sort of like if your doctor prescribed you a stool transplant.

Frass is also essential for thriving ecosystems. By breaking down complex plant materials into a form that bacteria and other organisms can more easily decompose, insects that distribute frass play vital roles in the food chain. The nutrients they leave behind eventually feed the plants that keep the planet healthy.

Frass and You

Unfortunately, your property is a far cry from some wild jungle. In residential and commercial spaces, frass usually indicates serious problems.

Since different kinds of insects produce distinctive frass, it can be hard to tell what you're dealing with unless you have some experience. Here are a few pointers:

  • Carpenter ants leave frass that looks like sawdust mixed with insect parts and dirt.
  • Termite frass typically takes the appearance of small, six-sided pellets.
  • Hornworm caterpillars, moths and other garden pests deposit frass on the plants they've been eating or on the nearby soil.
  • Roaches commonly produce frass that looks like black pepper.
  • Bed bugs, fleas and other insects that feed on blood leave behind hard flecks that appear dark maroon or black. This frass releases a reddish pigment when dropped in water.

Unless you're a gardener who's interested in finding a great plant fertilizer, then having noticeable frass inside your property is usually a bad sign. When you start to see droppings, it's time to take decisive pest control action. Contact F&W Pest Control today and let our team of professionals help rid your pest worries.

We proudly serve West Newton, MA as well as a large number of surrounding towns, including many in Rhode Island. Check out our service area pages to get a full understanding of locations we serve!

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