A psocid is a very small, soft-bodied pest that rarely grows larger than three-sixteenths of an inch long, making it difficult to spot. They are often confused with springtails, fleas, and lice. Other names include “barklice,” referring to the species of psocids that live outside, and “booklice,” referring to the types that live inside.

With the smaller species, there can be hundreds or even thousands of them, making a group more noticeable than an individual psocid would be.

Do psocids bite humans?

Unlike true lice, which may bite their human host several times a day to get a full blood meal, psocids do not bite. Their anatomy may suggest otherwise, however; as entomologists from Texas A&M University note, psocids have broad heads and a prominent clypeus, or area located near the mouthparts, that may give the impression that psocids can inflict bites on humans. Psocids do not bite or transmit disease, so they are no real threat to humans.

Are booklice harmful? The answer is no—you don’t have to worry about booklice bites, either.

What do psocids eat?

Psocids have a long, “chisel-like” upper jaw that ensures they are adept at chewing material. They primarily feed on fungi and other organic matter, and some species of booklice can be found in packages of flour, cereal, and other grains.

According to faculty from the UC Division of Agriculture and Natural Resources, it’s possible that you’ve unknowingly eaten psocids, or parts of them, in your pancakes, your oatmeal, or maybe even your chocolate birthday cake. Though eating psocids like booklice is not believed to pose harm to humans, the article also mentions that anyone worried about consuming food infested with psocids can bake the contents in their oven at 120 degrees Fahrenheit for 30 minutes, and then store the contents in an airtight container. This should kill any psocids still living in the material.

Preventing and removing psocids from your home

Other than being a slight nuisance, psocids don’t cause damage to the inside or outside of a home. Still, you may not want hundreds of tiny pests living with your family. Because these pests are drawn toward moisture, homes located in humid regions of the country may be more susceptible to a psocid infestation.

Generally, insecticides are not needed to get rid of psocids found indoors. Instead, it’s best to remove any infested items, like food products, and address any high levels of humidity that could be attracting them. Psocids cannot survive when the humidity falls below 45 to 50 percent, so using a dehumidifier or fan in damp rooms can help deter them. Likewise, it can be helpful to keep all books, papers, and cardboard boxes off the floor to limit their exposure to collected moisture.

But what about barklice? These types of psocids are natural outdoors and have even been considered beneficial to the trees they infest because of their tendency to feed on mold and fungi. To prevent barklice from coming inside, check rooflines for poor attic ventilation, trees overgrowing the roof, and leaf litter in the eaves. If needed, contact a professional like Terminix to help address these issues.

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