What Are Booklice & How to Get Rid of Them

In this article, we’ll explain what booklice are and how to get rid of them.

What Are Booklice?

Booklice, also known as psocids or paperlice, are group of small, wingless, soft-bodied insects that belong to the order Psocodea.

They primarily feed on mold and fungi, so they’re often attracted to dark, damp places where mold is likely to grow. They’re also known to scavenge for grains, pollen, dead insects, and starchy materials like wallpaper glue.

In general, booklice are harmless. They don’t bite, cause damage to property, or transmit diseases. To some people, however, the presence of booklice may cause allergic reactions. Certain species of booklice (of the genus Liposcelis) are also considered stored product pests that get into pantries and contaminate foods such as grains, flour, cereal, and pasta.

Booklice are often associated with the presence of mold in the home. They’re usually found in warm areas with high levels of moisture and humidity, such as:

  • Basements
  • Boiler rooms
  • Bathrooms
  • Kitchens and pantries
  • Laundry rooms
  • Storage rooms
  • Attics
  • Ductwork

And as their name suggests, booklice tend to infest places with lots of books, cardboard, and paper, such as libraries and warehouses. They don’t actually eat books though—they feed on the glue in book bindings as well as microscopic surface mold that grows on paper exposed to moisture or humidity.

What Do Booklice Look Like?

Booklice are tiny, light-colored insects (usually pale white, grey, or light brown). The typical household species usually measure between 1–4 millimeters long, which is about the size of a crayon tip.

As insects, they have 3 body segments, consisting of a wide head, a narrow thorax, and a large abdomen. They have 6 legs which are mostly thin, except for the hind pair which have enlarged femora.

On their heads, booklice have 2 long, filamentous antennae and a distinctively large bulge at the front called a clypeus. It somewhat resembles a big nose, but it’s actually the upper “lip” of the insect. Underneath the clypeus is a set of chewing mouthparts that includes a chisel-like upper jaw which booklice use to scrape and grind their food.

Lastly, booklice lack wings and cannot fly.

Due to their size, shape, and color, they are often misidentified for bed bugs or bed bug nymphs. However, booklice have narrow bodies and long antennae which are unlike that of bed bugs.

How to Get Rid of Booklice

1. Remove Mold and Mildew

Booklice infestations are commonly associated with mold growth, since that’s their preferred food. Throw out moldy or infested items (especially food products, cardboard, and other starchy materials) to eliminate potential food sources and hiding spots.

Removing mold and mildew from infested areas will also help prevent them from reproducing and spreading. For small patches of mold and mildew, we recommend using borax or vinegar, both of which are effective and natural cleaners.

Mix borax with water, using a ratio of one cup of borax to one gallon of warm water. Spray the solution on the affected areas and use a brush to scrub it clean.

2. Fix Moisture and Humidity Issues

It’s also important to address problems causing excess moisture or humidity in your home. Booklice require warm temperature and humidity to survive. Ideal conditions for booklice to quickly reproduce are temperatures between 75–82°F and relative humidity between 75–90%.

Reducing indoor humidity to a level below 50% kills booklice within 2–3 weeks, even without doing anything else, and keeping it that way prevents them from returning.

3. Vacuum and Clean

Vacuuming is a relatively simple and immediate way to get rid of booklice in your home, although it works best when you’ve already addressed the steps above (otherwise they’ll just repopulate).

Use a vacuum with a crevice attachment to suck up any booklice that you see. Make sure to also vacuum behind furniture and in tight spaces where booklice like to hide.

We recommend using a vacuum with a HEPA (High-Efficiency Particulate Air) filter if you have one, since these will also help capture the microscopic mold spores and organic debris that they feed on.

You’ll also want to wipe down any shelving that contains paper, food, and other starchy or organic materials. Any bedding or furniture where booklice have been found should also be cleaned or laundered.

4. Use Diatomaceous Earth

Food-grade diatomaceous earth is a powdery white dust that can be used to safely get rid of booklice and other soft-bodied insects (like bed bugs). It acts as a desiccant, which is effective against booklice which are highly dependent on moisture.

It’s made of fossilized remains of microscopic algae, which are ground up into tiny, jagged particles when viewed under a microscope. These particles get stuck to the bodies of booklice that walk through it, puncturing their waxy outer coating and causing them to dry out.

Lightly sprinkle the diatomaceous earth in areas where booklice are found. Make sure that the area is dry before applying, since diatomaceous earth is not as effective in wet or humid conditions. It usually takes 1–2 weeks for most of the booklice to be killed this way. We recommend vacuuming and reapplying it at least once a week until the booklice are gone.

As an important safety reminder, make sure that you’re using food-grade diatomaceous earth. Other types of diatomaceous earth (i.e. pool grade, garden grade, or filter grade) can be dangerous to humans and pets when breathed in.

If you can’t find diatomaceous earth, silica gel is another type of insecticidal dust that works in a similar way (getting rid of booklice through desiccation).

Tips for Preventing Booklice

The best way to keep booklice away is to control moisture and humidity in your home. Try to keep relative humidity below 60% and ideally between 30–50%, which is the proper range recommended by the EPA. This helps prevent both booklice and mold issues.

Other good ways to prevent booklice include:

  • Ventilate bathrooms and kitchens
  • Store grains and other dry foods in sealed containers
  • Keep books, paper, and cardboard off the ground and in dry areas
  • Vacuum, clean, and dust regularly

About MMPC

If you’re dealing with booklice and need some professional help getting rid of them, give MMPC a call today! We are a top-rated pest control company in New York City that provides comprehensive pest solutions using effective and eco-friendly methods.

If you live outside our service area, you’re still welcome to contact us if you have any questions about getting rid of booklice or other pests.