New York State IPM Program

July 19, 2016
by Matt Frye
Comments Off on Early Detection – Rapid Response

Early Detection – Rapid Response

I’m an urban entomologist with expertise in pest management, so you might think my house is free from pests. Not true. My recent adventure confirmed the importance of addressing an issue at the onset. Otherwise, things can get pretty ugly.

The Situation
A small portion of my basement is a dirt floor crawl space. When I moved in (August 2014) it was clear that this was not only a raccoon latrine, but mice had been nesting in the insulation above, so the dirt floor was covered in droppings and old cached food items. I sealed the exterior foundation from future intrusion and installed 5-mil thick plastic over the soil to reduce moisture and provide a good surface to crawl on for other projects that needed my attention.

My Mistake

A meal moth, Pyralis farinalis.

—A meal moth, Pyralis farinalis.

In the fall of 2015 I noticed a few meal moths (Pyralis farinalis) fluttering around the basement, which seemed pretty odd. Something made me look under the plastic and I saw that where there had been organic matter was now mold. Caterpillars were feeding in this area on the organic debris, leaving behind their pellet-shaped frass and head capsules. (Frass is caterpillar poop.)

And head capsule? Remember that caterpillar skin doesn’t grow along with the caterpillar. It needs to molt as it grows. The first thing it sheds is the skin around its head — the head capsule.

But back to my story. I decided that the mold was probably a bigger concern than the moths, so I kept the plastic down and decided I’d tackle the issue later.

Pellet-shaped frass and orange head capsules from caterpillars feeding.

—Pellet-shaped frass and orange head capsules from caterpillars feeding.

Beginning this spring, the number of moths in the basement rose steadily. When it warmed up, I decided to open the windows, pull up the plastic, and dry out the soil. Big mistake. For every moth flying around, there were a dozen more under the plastic. I had unleashed a blizzard of insects. Entomologist dream come true? Nope, not really.


—Mold and pellet-shaped frass.

What I Did
I removed moths from the walls with a handheld vacuum. Meanwhile I noticed two things about them:

  • they aggregate in certain areas, likely due to the presence of a female emitting pheromones
  • they’re negatively phototactic; they avoid light

This meant I could crawl in my dimly lit space to suck up dozens of meal moths at a time, reducing mating opportunities. Wearing the right gear — a HEPA mask, goggles and gloves — I turned the soil, opened the windows and used a box fan to keep the space dry. Even if more adults emerged (which they did), the larval food source was eliminated, preventing more breeding.

What I Should Have Done
As soon as I saw the first moth and found the source, I should have addressed the issue – the breeding material. The ideal solution was (and is) to remove the contaminated soil that holds frass and other organic material, then take it outdoors where it will degrade over time. Covering up a problem doesn’t make it go away but makes it worse.

The Lesson
If you come across a pest problem, attend to it right away. Identify and remove sources of food, especially breeding sites. It is much easier to deal with a small, confined population than a large dispersed one.

March 17, 2015
by Joellen Lampman
Comments Off on The squirrels are coming, the squirrels are coming!!

The squirrels are coming, the squirrels are coming!!

“Spring work is going on with joyful enthusiasm.” ― John Muir

In other words, birthing season will soon be upon us. And though it’s fun watching animal families grow up in our backyards, it’s best that they don’t give birth within our buildings. Because female squirrels seek safe places to raise their young in late winter and early spring, now is the time to ensure they stay out of your attic.

Photo credit: Carosaurus

Give them an opening and squirrels will happily turn your attic into a nursery. Photo credit: Carosaurus


Your first step? Monitoring is key to sound IPM. In this case you want to inspect your building exterior, especially if you’ve had problems in the past. Since squirrels are climbing animals and there’s no way could you see all possible entry sites from the ground, you’ll need a ladder. If you find a likely entry hole, don’t close it without first determining if it’s active. Trapping an animal (or its nest) inside can provoke it to chew its way back out — or in. Monitor an opening by inserting a soft plug (crumpled newspaper works fine) into the hole. If the plug is still there after two days and you see no other signs of activity inside the building, it should be safe to permanently close the hole. What to close it with? Think galvanized sheet metal or galvanized metal mesh, which resist strong teeth.

Do you need to remove squirrels from the building? Trapping is the most common and successful method. By New York law, however, without a state-issued permit squirrels must be released on the property or humanely destroyed. Another method is to install one-way doors (also known as excluders) over entry holes. These devices allow animals to leave — but not re-enter — the structure. To be successful, one-way doors need to be combined with preventive exclusion (such as metal mesh and caulk) on other vulnerable sites on your building, since exclusion and prevention are also key IPM practices.

Photo credit: BillSmith_03303

Openings such as this one provide access for squirrels, raccoons, mice, rats, birds, stinging insects, bats, snakes, … Photo credit: BillSmith_03303


No rodenticides or other poisons are legally registered for squirrel control. Although a variety of repellents and devices make marketing claims about driving squirrels from buildings, their efficacy is questionable.

To prevent future problems, reduce squirrel access to the building by keeping trees and tree branches at least 10 feet away from the structure and make sure all vents are made of animal-resistant materials.

For information on IPM for nuisance wildlife, refer to Beasts Begone!: A Practitioner’s Guide to IPM in Buildings  and Best Practices for Nuisance Wildlife Control Operators.

(Adapted from Controlling Squirrel Problems in Buildings by Lynn Braband, NYS Community IPM Program at Cornell University)

Skip to toolbar