Tree Worx Pros Facts About Tent Caterpillars

Six Cool Facts About Tent Caterpillars

Residential property owners who have a valued cherry tree might not be pleased to see silk tents emerge in the limbs every springtime. In vast numbers, tent caterpillars could consume practically all the leaves on a tree. If you take some time to observe them in action, you’ll soon see they’re brilliant insects. These intriguing facts about tent caterpillars might alter your opinion of these common pests.

Caterpillars are Sociable

It isn’t a coincidence that numerous tent caterpillars hang out collectively in a silk tent. Caterpillars are extremely social beings. There are over 25 known species of tent caterpillars, and every one of them displays social behaviors. 

The Silk Tent Functions as Their Home Base

Not all caterpillars build permanent, huge tents. However, some use their family tent as an operational base through the larval life stage. Eastern tent caterpillars start their lives by picking a location to construct their home. The tiny caterpillars search for a tree crotch that gets morning sun, and then each spins silk to add to their tent’s creation. 

Early instar caterpillars only need a small tent. However, as they grow, they increase their tent to house their larger size. Before every hunting trip, they fix and maintain their dwelling—the tent functions as a resting place between meals where the caterpillars get some safety from their predators.

Caterpillars use Pheromones to Mark Trails 

Tree Worx Pros Six Facts About Tent Caterpillars
A group of tent caterpillars crawl on a small tree trunk.

Numerous insects use chemical markers to talk to each other. Eastern tent caterpillars leave pheromone trails to beckon their siblings. Caterpillars do things in a somewhat unique way, using various pheromones to mark recruitment trails and exploratory trails. When a wandering caterpillar comes across an exploratory pheromone trail, it realizes another caterpillar is already surveying that limb for food and goes another way. 

If they find a limb flush with leaves, it beckons others to join the meal using its pheromones. If you spend time studying this species, you’ll observe it stops and inhales when it gets to the fork of a tree branch, trying to decide which direction to go.

They Keep Each Other Warm

Temperatures might alter, and nights could be cold. Eastern tent caterpillars do behavioral thermoregulation, taking steps together to regulate their body temperature. If they want to warm up, they might lie in the sun outside of their tent. 

Typically, they’ll gather together in tight clusters to reduce the impact of the wind. They construct the tent in layers, which lets them travel from level to level as the temperature necessitates. Conversely, if it gets too hot in the tent, the caterpillars will go over to the shady side and hang themselves separately to let it circulate between them.

They Can Cause Abortions in Mares

Grazing mares could easily consume caterpillars in the springtime, which is trouble for horse owners. Though usually harmless, tiny hairs known as setae cover these caterpillars. Setae could pierce a mare’s digestive tract wall. Contamination of the mare’s intestines creates bacteria in the amniotic sac and reproductive organs. 

After eating some caterpillars, pregnant mares may suddenly abort their late-term fetuses. A condition called mare reproductive loss syndrome (MRLS). During the times when caterpillar numbers are soaring, foal losses can be significant. Donkeys and mules could also abort their growing young after consuming them.

Outbreaks are Cyclical

Tent caterpillars are native forest pests. Despite their insatiable appetites, trees can recover from the harm they inflict. Some years are worse than others for invasions. The population of caterpillars peaks every 10 to 15 years, creating significant damage to trees. Luckily, these trends are cyclical. Therefore, after an exceptionally intense infestation year, there is usually a drop in the number of caterpillars. 

For more information on tent caterpillars, talk to the experts at Tree Worx.