What Eastern Tent Caterpillars Eat

Eastern Tent Caterpillar

ENTFACT-423: Eastern Tent Caterpillar|Download the PDF version of this fact sheet

by Ric Bessin, Extension Specialist University of Kentucky College of Agriculture

The eastern tent caterpillar, Malacosoma americanum, is a North American insect that is a nuisance to both humans and animals. Populations change from year to year, with epidemics happening every few years or even more often. This bug is a nuisance in the late spring and early summer because of the defoliation of trees, the construction of unattractive silken nests in trees, and the presence of roaming caterpillars crawling over plants, sidewalks, and roadways. Eastern tent caterpillar nests are most usually seen on wild cherry, apple, and crabapple trees, but they can also be found on other trees such as hawthorn, maple, cherry, peach, pear, and plum.

Figure 1. An eastern tent caterpillar.

While tent caterpillars may almost completely defoliate a tree when they are in large numbers, the tree will typically rebound and produce a new crop of leaves. Nests, on the other hand, can constitute an eyesore in the landscape, particularly if they are exposed as a result of extensive defoliation. The silken nests, which are formed in the crotches of limbs, can grow to be rather substantial in size. As soon as the larvae begin to roam in search of safe havens to pupate, there is tremendous anxiety.

They are a nuisance and may cause a sloppy mess if they are squished on driveways, sidewalks, and patios, for example.

In general, insecticides are ineffective against fully developed larvae.

Fall webworm nests, in contrast to the tent caterpillar’s, are found at the extremities of branches, and their loosely formed webs include foliage, but the tents of the eastern tent caterpillar do not.


The eastern tent caterpillar overwinters as an egg in a mass of 150 to 400 eggs, which is the size of a grapefruit. In this case, the masses are covered with a glossy, black varnish-like substance and wrap branches that are approximately the size of a pencil or less in diameter.

Figure 2. Eastern tent caterpillar egg masses are wrapped around small twigs.

The caterpillars hatch about the time that the buds begin to open, which is normally in early March, and feed on the buds. These insects are very sociable; caterpillars from a single egg mass will remain together and create a silken tent in the crotch of a tree to protect themselves from predators. Caterpillars from two or more egg masses may congregate to create a single big colony if the conditions are right. They remain within the tent when it is too hot outside or when it is too wet outside.

Figure 3. An eastern tent caterpillar nest.

A row of oval blue dots on the sides of the caterpillars, which are black with a white stripe down the back, brown and yellow lines along the sides, and a black and white stripe down the rear. In order to consume the leaves, the larvae enlarge the web, which eventually grows to be a foot or more in length. They are fully developed and 2 to 2-1/2 inches in length after 4 to 6 weeks of development.

At this point, they begin to disperse from the nest in search of safe places in which to construct a cocoon on their own. Approximately 1 inch long and formed of tightly woven white or yellowish silk, the cocoon is linked to other items by a few coarser strands that run through it.

Figure 4. An adult male eastern tent moth.

The adult moth emerges from the cocoon around 3 weeks after the cocoon is laid. In coloration, the moth is reddish-brown with two faint stripes running diagonally across the forewings of each of its wings. Female moths mate and begin to deposit eggs on short branches after mating. The eggs will hatch in the spring of the following year. Every year, just one generation is produced.


  • In most years, natural enemies play a significant role in lowering the population of eastern tent caterpillars on the ground. Caterpillars are regularly parasitized by a variety of small braconid, ichneumonid, and chalcid wasps, which can be found in abundance in the wild. Some predators, as well as a few illnesses, contribute to the control of their populations. This, in part, explains why population levels fluctuate from year to year
  • Prevention and early management are therefore critical. The removal and destruction of egg masses from ornamentals and fruit trees over the winter months helps to significantly lessen the problem the following spring. Small tents may be easily removed and destroyed by hand in the early spring months. It is possible to prune out larger tents that are then destroyed or removed by twisting the nest around the end of a stick. It is not advisable to burn the tents out with a torch because this might cause significant harm to the tree. It is possible to kill young caterpillars by spraying them with a pesticide containing Bacillus thuringiensisvarkurstaki. Carbaryl and malathion are two more pesticides to consider. It is more difficult to destroy larvae under tents because they are shielded beneath the webbing.

Date of last revision: 11/19 CAUTION! The pesticides recommended in this book are only approved for use in Kentucky, United States of America. Some goods may not be legal to use in your state or nation, depending on where you live. It is recommended that you consult with your local county agent or regulatory authority before applying any pesticide listed in this article. As a reminder, ALWAYS READ AND COMPLY WITH LABELED INSTRUCTIONS FOR SAFE USE OF ANY PESTICIDE! Images courtesy of Ric Bessin, University of Kentucky Entomology, with the exception of the tent in the tree shot, which is courtesy of R.

Anderson, USDA Forest Service, copyright 1995.

Tent Caterpillars

ENTFACT-424: Tent Caterpillars|Download the PDF version of this fact sheet

by Joe Collins, Nursery Inspector University of Kentucky College of Agriculture

Tent caterpillars are nocturnal creatures that dwell in groups under a silken tent. The silk is generated by glands in the head, and the tent protects the creature from a variety of natural predators and predatory insects. Tent caterpillars are found in three different species in Kentucky, the United States: the eastern tent caterpillar, the forest tent caterpillar, and the autumn webworm. Each of these pests has a diverse range of natural enemies that, in most cases, prevent caterpillar populations from getting excessively numerous.

During certain years, one or more of the species may, on the other hand, become quite prevalent.

However, excessive feeding within a single year may cause tree development to be stunted, particularly if the tree is subjected to additional pressures such as drought.

Eastern Tent Caterpillar

Larvae of the ETC A native bug, the eastern tent caterpillar was originally described in 1646 and has been around ever since. The appearance of large numbers of this caterpillar is frequently associated with intervals of around 10 years. For a long time before the gypsy moth was unintentionally imported into the United States, the eastern tent caterpillar was thought to be one of the most serious pests of shade trees in our country. Among the fruits that eastern tent caterpillars like are wild cherry, apple, and crabapple.

  • They will also eat The bug hibernates as an egg during the winter.
  • The egg masses are approximately 3/4″ in length and have a varnished appearance.
  • Following the hatching of their eggs, the little caterpillars proceed to create a tent in a nearby branch fork.
  • The larvae crawl out of this tent and into the surrounding vegetation to feed.
  • The larvae are usually black with a white stripe running down the back of their bodies.
  • This insect pupates inside of whitish-colored cocoons that may be seen on tree trunks, fences, and buildings, amongst other places.

The moths are reddish-brown in color with two white lines running across each wing on each of their wings. This bug reproduces just once a year and has only one generation every year. Tent (on the left) and ETC Egg Mass (on the right) (right)

Forest Tent Caterpillar

Larvae of the Federal Trade Commission The woodland tent caterpillar resembles the eastern tent caterpillar in appearance and behavior. The egg masses are laid in a manner identical to that of the eastern tent caterpillar, with the exception that they are square at the ends. When the eggs hatch, the larvae attach themselves to the trunk or limb of a tree and form a loose tent or mat. As a result, they will normally travel to the top of the tree where they will begin feeding on the developing leaves buds.

  1. A typical eating pattern for the larvae is to focus their feeding on a single branch at a time.
  2. In comparison to the eastern tent caterpillar, this caterpillar is differentiated by the keyhole-shaped markings that run along its back.
  3. Larvae are about the size of a pea.
  4. Each of the front wings has two dark brown stripes on each side, and the adult is a tan moth approximately 1-1/2 inches long with two dark brown stripes on each side.
  5. Sweetgum, oak, birch, ash, maple, elm, and basswood are among the trees that have been damaged by this insect.

Fall Webworm

In the United States and Canada, the autumn webworm is a pest that may be found throughout the majority of the country. With the exception of evergreens, it will feed on practically all shade, fruit, and decorative trees. The American elm, maples, hickory, and sweetgum are among the trees that are particularly popular in Kentucky. Larvae of the Fall Webworm When compared to the eastern tent caterpillar and the forest tent caterpillar, the autumn webworm is distinguished by the fact that it always places its tent at the ends of branches and that there is generally more than one generation every year of development.

  • They can have either a red or a black head on their bodies.
  • A frail web will be formed by the blackheaded larvae, but a huge and thick web will be formed by the redheaded larvae.
  • The moths begin to emerge between the middle of March and the middle of late April.
  • Female moths lay their eggs on the underside of leaves in masses ranging from 200 to 500 eggs in size after mating.
  • The first generation of caterpillars begins to feed from the middle of spring through the beginning of summer.

It is during August or September that a second generation of webworms will be spotted, after they have finished eating. Defoliation caused by webworms is often greater in the second generation than in the first generation. Tent for Webworms in the Fall


Essentially the same methods are used to control all three of these pests. It is quite effective to destroy the tents, especially if the tents are tiny, in order to get rid of the caterpillars. If possible, wait until dusk or early morning when the larvae are most active in the tent before doing this. It is best not to burn the tents since the tremendous heat and flames may cause harm to the tree’s roots. It may be necessary to prune egg masses off smaller trees in order to prevent their reproduction.

  1. These caterpillars are resistant to the bacteria Bacillus thuringiensis (Bt) as well as a variety of chemical pesticides.
  2. When the insects are in the nest, it is best to apply the pesticide in the evening or early morning when they are most active.
  3. 1/04 – Date of last revision: CAUTION!
  4. Some goods may not be legal to use in your state or nation, depending on where you live.
  6. The photographs of the Eastern tent caterpillar tent and egg mass, the forest tent caterpillar larva, and the fall webworm tent were taken from the CD: G.K.
  7. I and II, Southern Cooperative Series Bulletin No.
  8. Douce, et al., 1995, Forest Insects and Their Damage Vol These are photos that have been copyrighted.
  9. A signed license from the SFIWC and each individual photographer or organization is required before any commercial or other usage of the photos can be made.
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All About Eastern Tent Caterpillars

Essentially, the methods for controlling all three of these pests are identical. A good technique to get rid of the caterpillars is to demolish the tents, especially if they are tiny and easily dismantled. If possible, wait until dusk or early morning when the larvae are most active in the tent before doing this. – It is best not to burn the tents since the tremendous heat and flames may cause harm to the tree’s trunk. It may be necessary to trim egg masses from smaller trees in order to prevent further damage.

  1. These caterpillars are resistant to the bacteria Bacillus thuringiensis (Bt) as well as a variety of chemical insectsicides.
  2. When the insects are in the nest, it is best to apply the pesticide in the evening or early morning.
  3. 1/04 – Date of last revision CAUTION!
  4. You should check with your local authorities before using any items.
  6. The photographs of the Eastern tent caterpillar tent and egg mass, the forest tent caterpillar larva, and the fall webworm tent were taken from the CD: G.K.
  7. I and II, Southern Cooperative Series Bulletin No.
  8. Douce, et al., 1995, Forest Insects and Their Damage, All of the photographs on this page are protected by intellectual property rights.

A signed license from the SFIWC and each individual photographer or organization is required before any commercial or other usage of the pictures is permitted.

What Do They Look Like?

Caterpillars of the eastern tent species feast on the leaves of several popular decorative landscape trees, causing their presence to be a source of concern for many homeowners. In reality, they seldom cause enough harm to a healthy plant to cause it to die, and if you’re looking for an intriguing bug to see, this is the one to look for. Several hundred caterpillars live in a communal tent constructed in the crotch of tree branches, where they are protected from the elements. The eastern tent caterpillars, which are models of cooperation, live and work in peace with one another until they are ready to pupate.

They grow to be almost 2 inches long and have noticeable hairs down the sides of their bodies by the time they reach their last instar.

Broken lines of brown and yellow flow along the sides, accented by oval specks of blue in the center of each line.

They lack the vibrant colors of many other moths and look nearly dull in comparison.


Caterpillars of the eastern tent eat the leaves of some of the most popular decorative landscaping trees, which causes their presence to be a source of concern for many homeowners. While they may do significant harm to a plant, they are rarely fatal, and if you’re looking for a fascinating bug to study, this is the insect you should look out for! In their silken tent, which has been constructed in the crotch of tree branches, many hundred caterpillars live in communal living quarters with one another.

  • It is in the early spring when the caterpillars first appear.
  • An elongated white stripe is visible down the backs of the black larvae.
  • Three weeks have passed since the Malacosoma americanummoths emerged from their cocoons.
  • Two parallel bands of cream are seen across the tan or reddish brown wings when examined closely.

What Do They Eat?

Cherry, apple, plum, peach, and hawthorn trees are among the plants where eastern tent caterpillars dine on the leaves. When the caterpillar species Malacosoma americanum is in abundance, the enormous number of caterpillars can defoliate its host trees completely before moving on to less desirable plants to feed on. Adult moths only survive a few days and do not consume any food.

Life Cycle

Eastern tent caterpillars go through a complete metamorphosis, which includes four phases, as do all butterflies and moths:

  1. Eggs- In the late spring, the female oviposits 200–300 eggs, depending on the species. Caterpillars emerge from the egg mass in a few of weeks, but they stay dormant in the egg mass until the next spring, when new leaves grow. During the sixth instar larval stage, the sixth instar larva creates a silken cocoon in a secluded area and pupates within it. The pupal case is brown in color. Adult- Moths fly around in quest of mates throughout the months of May and June, and they only survive long enough to breed.

Special Adaptations and Defenses

During the early spring months, when temperatures are more volatile, larvae emerge. The caterpillars dwell in large groups in silken tents that are meant to keep them warm during cold spells of weather. On cold or wet days, the broadside of the tent faces the sun, and caterpillars may congregate there to warm themselves. Each of the caterpillars’ three daily feeding expeditions begins with a thorough cleaning and replenishment of silk in their tent. In order to fit their growing size and to get away from the accumulating waste of frass, the caterpillars build additional layers to their body as they mature.

  • As they move through branches and twigs in search of leaves to eat, they leave behind silk trails and pheromones that attract other insects to the area.
  • Pheromone signals not only warn other caterpillars to the presence of foliage, but they also convey information about the quality of the food available on a certain branch of a plant.
  • Whenever they sense a threat, the caterpillars leap to their feet and thrash their bodies about.
  • When the caterpillars need to rest between feedings, they return to the shelter of the tent, which also serves as a protection against predators.

Where Do Eastern Tent Caterpillars Live?

It is possible for eastern tent caterpillars to infest the residential landscape, forming tents in ornamental cherry, plum and apple trees, among other species. It is possible that roadside stands of trees will produce adequate wild cherries and crabapples, and that dozens of caterpillar tents will embellish the forest border in this area. Because these early spring caterpillars need on the warmth of the sun to keep their bodies warm, tents would be unusual, if at all, to be seen in wooded places that were shaded.

Malacosoma americanum is a kind of bug that is indigenous to North America.


  • Caterpillar of the eastern tent. The Texas A&M University tent caterpillar is an Eastern tent caterpillar. T. D. Fitzgerald is at the University of Kentucky Agriculture Department. Stephen A. Marshal’s novel The Tent Caterpillars is set in a tent. Insects: A Natural History and Diversity of the Species

Eastern Tent Caterpillar Moth

Two light-colored stripes cut across the forewing of the adult eastern tent caterpillar moths distinguish them from other moths. The center band between the two lines might be lighter or white in color at times. These moths are similar in size to others in their family, and they have thick, lengthy scales that give them the appearance of being fuzzy. Feathered antennae are found on both males and females. Females are lighter and more golden in color, as well as bigger and more rounded in their wings.

  • They live in groups in “tents” formed of numerous silken threads in the crotches of host trees, which they construct from the strands.
  • The inside of the head is dark.
  • disstria) has black (rather than pale) lines on the forewings, but the forest tent caterpillar (M.
  • The larvae do not have a continuous line down their backs; instead, there is a light-colored mark on each segment down their backs, with the form of each mark resembling a keyhole, shoeprint, or bowling pin on each segment.

In addition, the communal larvae of that species do not construct tents as they do in other species. Instead, they merely construct silken mats and recommendations on tree trunks and branches to direct them to and from feeding areas and group meeting areas.

Food for caterpillars, food for birds: Cherry trees and Eastern tent caterpillars, Malacosoma americanum — Bug of the Week

The eastern tent caterpillar is a stunning creature, with blue stripes and patches on the sides and a white stripe along the middle of the back to distinguish it from its competitors. The return of eastern tent caterpillars is heralded by the blooming of forsythia. Even while the forsythia’s vivid yellow blooms herald the arrival of spring, they also herald the arrival of an outstanding defoliator known as the eastern tent caterpillar. Since last summer, this herbivore has survived by laying eggs in large numbers on the short branches of cherry, apple, and crabapple trees, among other fruit trees.

  1. Thousands of tiny caterpillars were produced from egg masses that looked like Styrofoam and contained as many as 300 eggs apiece.
  2. Larvae construct little silken tents over the egg mass and the surrounding branch to protect themselves from predators.
  3. Pheromones, which are chemical trail markers, are deposited by the caterpillars when they return to their tent after eating.
  4. During the month of April, the larvae’s tents develop in size.
  5. Caterpillars returning to the tent from a meal pass hungry caterpillars on their way to eat fragile leaves along the silk route.
  6. Brothers and sisters from the same egg mass or from neighboring egg masses frequently participate in group activities like as communal foraging and the expansion of their magnificent tent, which they built for themselves.
  7. Besides providing shelter against predatory or parasitic insects, their silken dwellings may also give some protection from the elements.

As soon as the larval feeding is through, the grownup caterpillars begin to travel and seek for safe havens like as cracks in loose bark where they may construct silken cocoons.

The larvae leave the tree and travel the land in search of protective areas beneath logs or leaves or stones, as well as under man-made structures, where they will construct yellowish or white silken cocoons.

They mate and deposit egg masses on the tiny branches of rosaceous trees such as cherry, apple, and crab apple.

What is the best way to tell whether eastern tent caterpillars are a hazard to your trees?

A little stand of wild cherry trees that is constantly plagued with eastern tent caterpillars provided the inspiration for this week’s Bug of the Week photo gallery.

Egg masses resemble rigid foam collars that have been coated with a shiny varnish-like substance and fully wrap twigs and tiny branches, according to the description.

On a chilly or gloomy day (when the caterpillars tend to stay in their nests rather than going out to feed), tents and their inhabitants can be removed with a gloved hand and disposed of in a trash bag.

Flames are extremely harmful to the bark of a tree and should never be used on one.

Another solution may appeal to you if, on the other hand, you want to let Mother Nature take her course and can live with the presence of caterpillars in your garden.

Caterpillars are a vital source of protein for birds in the spring, both during the development of eggs within their bodies and afterwards, when the eggs hatch and the ravenous broods require fresh meat to survive.

If you wish to safeguard your valued trees from defoliation by tent caterpillars while also assisting your local birds, you may simply trim away the afflicted branches, tents and all, and transplant them to a neighboring feral cherry or a nearby wild cherry.

Tent caterpillars are voracious eaters, and they may wreak havoc on small and even huge trees.

While trees may rebound and produce a second flush of leaves, the recurrent defoliation of these trees is certain to have a negative impact on them.

See also:  What Is The Best Way To Heat A Tent In The Winter Without Gas Fumes

The active components Bacillus thuringiensis(Bt) or spinosad, which are commonly found in pesticides licensed for use against caterpillars, can give good control of these small leaf eaters for those who want to do it themselves.

Take extra precautions if plants are in flower or if helpful pollinators are around.

Naturally occurring predators, parasites, and viruses are generally able to decrease tent caterpillar populations to insignificant levels after only a few years of high caterpillar abundance.

To find out what these fascinating herbivores are up to this week, get out to the garden and take a look around.


This episode was inspired by the fantastic books “The Tent Caterpillars” by Terrence Fitzgerald and “Managing Insects and Mites on Woody Landscape Plants” by John A. Davidson and Michael J. Raupp, both of which can be found on Amazon.com and in libraries everywhere. Visit the following websites for further information about eastern tent caterpillars:

Eastern Tent Caterpillars and Forest Tent Caterpillars on Trees

Crabapple is host to eastern tent caterpillars. Photograph courtesy of David L. Clement of the University of Maryland and Bugwood.org

Key points

  • The eastern tent caterpillar’s webs are a frequent sight in the springtime anywhere wild cherry trees may be found in abundance. The presence of this insect is first detected by the appearance of unattractive webs in the forks of trees. The caterpillars spend the night hiding in the webs and feeding among the leaves during the day. Cherry trees are their preferred host plant, and they are often the beginning point for outbreaks of eastern tent caterpillars in the United States. After the caterpillars have devoured all of the cherry leaves, they will frequently move to other neighboring trees and munch on their leaves as well. Crabapples and hawthorns in bloom are routinely targeted for destruction. In some locations, large outbreaks of peach, plum, witch hazel, rose, beech, birch, willow, and poplar trees may occur every ten years on trees such as peach, plum, witch hazel, rose, beech, birch, willow, and poplar

Egg mass of the eastern tent caterpillar. Photo courtesy of Brian Kunkel of the University of Delaware and Bugwood.org

Life cycle

  • In one inch long, black, gall-like lumps on slender twigs, the overwintering eggs are protected from the elements (see photo above). They are covered with a protective layer that feels similar to styrofoam. In central Maryland, the eggs hatch around the first week of April, depending on the meteorological conditions at the time. Occasionally, this will occur even before the wild cherry buds have opened. Young caterpillars are totally black
  • Older caterpillars are brown. After a few days, they begin to spin the silk tents, which they continue to develop in size. During their development, Eastern tent caterpillars grow an unique white stripe running down the rear of their bodies (see photo below). When forest tent caterpillars reach adulthood, they develop spots on their backs. During the month of May, the huge caterpillars that develop by the end of May do the greatest amount of feeding damage. As soon as they have finished eating, they depart the trees in search of safe havens where they may build protective cocoons. When the little brown moths emerge from their cocoons in the early summer, they mate in order to lay the overwintering eggs. A single generation happens in Maryland each year
  • There are no more.

Eastern tent caterpillar (right) has a white stripe, but forest tent caterpillar (left) has keyhole-shaped white dots on its wings. Photo courtesy of Ronald S. Kelley of the Vermont Department of Forests, Parks, and Recreation and Bugwood.org

Forest tent caterpillar

The forest tent caterpillar differs from the eastern tent caterpillar in that it has a sequence of white dots along the back (as shown in the photo above), rather than a complete white stripe. Unlike wild cherry, it does not build a tent, and favours oak and other shade trees above other types of trees. The life cycle of the western tent caterpillar is quite similar to that of the eastern tent caterpillar.


Caterpillars have the ability to defoliate whole cherry trees in extreme epidemics. However, defoliation typically happens early enough in the season for wild cherries to replace the eaten leaves with new ones, preventing the trees from succumbing completely. Other tree species, on the other hand, may be destroyed because they do not have enough time to establish a fresh set of leaves for food production and storage, which is necessary for winter survival. The larvae of the eastern tent caterpillar.

Cultural control

  • As far as is practicable, wild cherry trees should be removed from hedgerows and fields next to properties that contain valuable ornamentals that are vulnerable to tent caterpillar infestation (such as blooming crabapple and cherry trees). The dormant season is the best time to cut away and kill twigs that have egg masses on them. To remove the expanding tents with their caterpillars, strong gloves might be worn by individuals who are not frightened by the prospect of ripping them out.

Biological control

As soon as the silk tents are visible in the early spring, apply Bt (Bacillus thuringiensis) to the crop if spraying is necessary. It is a naturally occurring pesticide that is solely effective against caterpillars. Bt is completely non-toxic to people and animals. It has to be sprayed on the leaves that the caterpillars will be feeding on. Bt must be used in April since only juvenile caterpillars are extremely vulnerable to this pesticide at this time of year. Thuricide is marketed under a variety of brand names, including Dipel, Caterpillar Attack, Biotrol, and others, and is available in several forms.


The use of trade names does not imply sponsorship on the part of the University of Maryland Extension staff.

The return of tent caterpillars: What’s it means for your yard?

Bud break does not just herald the advent of flowers and foliage; it also heralds the emergence of tent caterpillars from their cocoons. Troops of these caterpillars may completely cover tree branches with their silk tents in as little as a few weeks. Is it necessary for you to be concerned about them? Continue reading to find out! Caterpillar tents are a common type of western tent. These tents are commonly found in the bends of large branches on trees and medium-sized bushes, although they can also be seen on the ground.

  • There are three species of tent caterpillar that may be found in Indiana: the Forest tent caterpillar (Malacosoma disstria), the Western tent caterpillar (Malacosoma californicum), and the eastern tent caterpillar (Malacosoma elatior) (M.
  • All three species dwell in groups of anything from 40 to 200 individuals, and they remain together until just before they pupate, at which point they split off.
  • They are not particularly gregarious, although they will leave pheromone trails leading to trees that have rich food sources.
  • Below you’ll find a few of ways for distinguishing them from other species.
  • If a tent caterpillar’s body is coated in fuzzy hairs, it is not a tent caterpillar; if it is smooth or spikey, it is not a tent caterpillar.
  • These tufts are absent in tent caterpillars.
  • If the caterpillar you’re looking at doesn’t exhibit any of these characteristics, it’s most likely not a tent caterpillar at all.

slate blue with a pair of black stripes, and C.



Elizabeth Barnes.

Hoff, C.

Hoff What exactly do they eat?

They are particularly fond of plants belonging to the Rosaceae family, such as cherry, apple, and chokecherry, among others.

What kind of harm do they cause?

Tent caterpillars typically defoliate only a few branches and are only actively feeding for a few weeks at a time.

However, if the tree is defoliated for a number of years in a row or is subjected to another stressor such as drought, it may suffer branch loss or even death.

If you decide that you want to get rid of tent caterpillars from your trees, you have a variety of choices to choose from.

Wait until the majority of the caterpillars have gathered in their tent before removing the tent from the tree and placing it in a bag to be frozen for later use.

Because their hairs might create an allergic response in some people, you may wish to use gloves when removing them off their tree.

If you believe you’ve discovered tent caterpillars but aren’t sure, please contact the author or post your find oniNaturalistorBugGuidefor ID assistance!

Eastern Tent Caterpillar

Caterpillar, Malacosoma americanum (Fabricius) (Lepidoptera: Lasciocampidae), tent caterpillar of the eastern hemisphere Drees captured this image. Caterpillar with the common name “Eastern tent caterpillar” Malacosoma americanum is the scientific name for this species (Fabricius) Order:Lepidoptera Description: They are brown and yellowish in color with two diagonal lines on the forewings of the adult tent caterpillar moth, which has a 1-inch wingspread. Caterpillars (larvae) can grow to be more than 1-12 inches in length.

  • They are distinguished by a solid white line running down the middle of their backs.
  • At night and during rainy spells, larvae construct a dense silken web, which is commonly found in the crotch of little limbs and which serves as a safe haven for them.
  • Forest tent caterpillar,M.
  • It does not build a tent and can be found on a variety of hosts, however oaks are the preferred host in Texas, according to the species.
  • californicum (Packard), makes huge tents on a variety of trees and plants, including oaks and wild plums, and may be found throughout the western United States.
  • The Sonoran tent caterpillar, M.
  • Caterpillars have one black segment on their back, but they do not have any white markings.

Fall webworms construct loose silken webs surrounding the leaves on which they are eating, rather than thick webs in the crotches of branches where they are leaving to feed, as they do in the spring.


took the photograph.

The larvae hatch in the early spring, just as the plants are beginning to leaf out (mid-February to mid-March).

Due to the fact that tent caterpillars only produce one generation each year, all activity is generally completed by May or June.

Caterpillars have mouthparts that are designed for chewing.

Eastern tent caterpillars love the fruits of cherries, plums, peaches, apples, hawthorn, and other similar trees and shrubs.

Leaving their tents to feed on leaves, caterpillars may swiftly defoliate whole parts of a tree in short periods of time.

Adult moths are drawn to lights and can be found in large numbers, although they only live for a few days before dying.

You may also contact your local Texas A M AgriLife Extension Service agent or look for other state Extension offices for further information. Literature citations: Jackman 1988; Metcalfe and colleagues 1962.

Eastern Tent Caterpillar Moth (Malacosoma americanum)

Updated on January 3, 2022; written by a member of the staff; content from www.InsectIdentification.org The Eastern Tent Caterpillar Moth derives its name from the activity of its caterpillars, which is why it is called that. A group of juvenile caterpillars works together to construct a “tent” out of their silk, which they use as a home on the tree or shrub from which they are eating. As they consume their food, the yellow and black meal worm-like caterpillars come and go during the day, returning at night for refuge from the environment and any predators.

  1. The feeding activity causes dead leaves and fruit to become trapped inside the branch, resulting in unattractive branches.
  2. Two thin, but clearly visible white lines cross their forewings in the middle and bottom part, respectively.
  3. The thorax is coated with a thick layer of brown hair.
  4. In the vicinity of roses and fruit trees like as apple, cherry, and peach, where they are most likely to deposit their eggs, they can be observed in large numbers.
  5. Because the caterpillars feed on the leaves of trees that produce fruit that humans consume, they are sometimes referred to be pests.
  6. Malacosoma americanum is the scientific name for this plant.
  7. Furry; uneven; flying are some of the descriptors.
See also:  How To Insulate Tent Walls

Dimensions (mm): 35.5mm Hi: 41 millimeters Reach Across Territories (A-to-Z) The United States, Canada, and Mexico Territorial Map of the United States, Canada, and Mexico NOTES ON THE MAP: The Eastern Tent Caterpillar Moth is represented by the color red on the territorial heat map above, which shows the states and territories in North America where the moth may be found (but is not limited to).

  • Some insects are naturally restricted by their habitat, weather, mating behaviors, food supplies, and other factors, but others have seen significant growth throughout most of, if not all of, North America, thanks to human intervention.
  • For the most part, insects roam freely, often prompted by changes in nutrition or habitat, as well as mating patterns.
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Controlling Eastern Tent Caterpillars in Your NJ Landscape

You have no idea who is sleeping under your trees’ leaves in silk tents and consuming their whole supply of leaves. The caterpillar in question is most likely the Eastern tent caterpillar. The Eastern tent caterpillar (Malacosoma americanum) is a natural insect in its larval (immature) stage that is easily identified by its silk “tents.” The Eastern tent caterpillar is also known as the tent caterpillar. The mature stage, on the other hand, is usually not something you notice. During the summer, adult moths may be seen in your garden, and they have a limited lifetime compared to the rest of the population of the species.

Thousands of caterpillars might be devouring your trees the next spring as a result of this development.

How to Recognize the Eastern Tent Caterpillar

See if you can find this bug in the trees that it favors. These are mostly apple (Malus) and cherry (Prunus) tree species, and they include the following:

  • Almond, apple and crabapple, apricot, peach, pear, plum, hawthorn, wild cherry, mountain ash (Sorbus), and other trees and shrubs

Look For Egg Masses

Look for eggs on these trees during the fall and winter months. The egg masses deposited by the female moths are tiny, black, and have a glossy appearance, indicating that they are freshly placed. It is common to find them on branches, with the mass of flowers completely around the limb. Because they’re so little, you may have to search for them for quite some time. These masses remain in situ throughout the winter and hatch out in the spring. You may see a picture of an egg mass by clicking here.

Spot Adult Caterpillars

Unlike the larval stage, the adult Eastern tent caterpillar is black and hairy. It features white stripes going down the length of its body, with thinner brown and yellow lines running down the sides, as well as blue patches on its back. When completely developed, it is around 1.5 to 2 inches in length.

Watch Out For Tents

The emergence of eastern tent caterpillars coincides with the emergence of the host tree’s fresh spring leaf growth. You’ll notice them as soon as they begin to form their distinctive “tents” or spun cocoons on branches and in branch crotches, which are easily identifiable. They also increase their tents when they begin to devour the tree’s buds and leaves and develop, which coincides with the growth of the caterpillars. In summer, the adult moths emerge from their cocoons and begin their life cycle all over again.

However, during this point of their development, you will not see the caterpillars eating any leaves and instead will find them traveling over sidewalks, along highways, and up buildings in their hunt for a cocoon location.

Tree Damage Caused by Eastern Tent Caterpillars

Trees bring forth fragile, juicy new leaves and buds in the spring, and caterpillars gorge themselves on them. Damage can range from mild to severe depending on the quantity of caterpillars present, as well as the size and condition of your trees. Often, the larvae consume the whole canopy of leaves of a tree. The majority of the time, this type of damage is simply a cosmetic concern.

Caterpillar damage of this magnitude often weakens the tree only after three or more years of defoliation more than 50% of the tree’s canopy. Because the number of this insect fluctuates year after year, it is rare that you would have three years of severe defoliation in a succession.

3 Options for Dealing With Tent Caterpillars

Depending on your degree of comfort, you may choose to use a variety of methods to manage or eliminate Eastern tent caterpillars from your trees.

Option 1 – Leave them Alone

If your trees are in good health and the caterpillar population is not overpowering, staying put is typically the best course of action. Once the caterpillars have caused significant spring leaf damage for a month or so, they will cease eating. Your trees will continue to develop throughout their life cycle, with little or no negative impact on their overall health in most cases. Because tent caterpillar populations fluctuate from year to year, you may have many years of low tent caterpillar populations and no leaf damage.

Option 2 – RemoveDispose of Them

If you are unable to leave them in situ, the quickest and most effective methods of removing egg masses or spun tents are to remove them by hand or to cut out the afflicted branches. It is simplest to remove egg masses from deciduous host trees in the winter, when the branches of the host trees are bare. The eggs may be killed by simply removing the eggs off the tree and burning them or soaking them in soapy water. When you notice tents in the spring, you may take them down. This is a simple task that may be completed by hand or with long-handled garden equipment.

  1. If you notice Eastern tent caterpillars in your tree, you have a few options for what to do next.
  2. To clean up after yourself after removing the nest by hand, simply put it into a bucket of soapy water.
  3. The larvae will not survive if they do not have access to light and nourishment.
  4. NOTE: If you are apprehensive about handling either eggs or caterpillars, trimming is a preferable alternative than planting.
  5. Pruning away an excessive number of branches strains a tree, especially during the warm spring months when the tree is already exerting considerable energy to produce leaves and blossoms.

Option 3 – Spray With Insecticide

Another technique of control is to treat the tree with a pesticide before it blooms or grows. This has the potential to lower the population of caterpillars that are capable of reproducing, hence reducing the caterpillar population the following year. Spraying is effective provided it is done appropriately and at the appropriate time. Non-toxic insecticides, in particular, must be administered at the appropriate stage of an insect’s life cycle and at a time when the sprays would not harm other insects in the vicinity.

Bacillus thuringiensis (B.t.) is the most ecologically friendly biological control approach available, but it must be sprayed in May in order to be successful.

These insecticides, on the other hand, can kill other beneficial insects that you may wish to have in your garden. There are various varieties of parasitic wasps that naturally destroy tent caterpillars, which are among the helpful insects you should look for.

What NOT to Do!

Using fire to burn off the caterpillar webs is not recommended. While using a flame torch may be enjoyable, you will only cause damage to your tree by burning the bark. Under addition, in dry circumstances, blazing tents and leaves have the potential to spread fire to other places.

What to Do If Your Tree Has Been Defoliated

If your trees have been defoliated by the Eastern tent caterpillar, we recommend that you water them on a regular basis and treat them with organic fertilizer to help them recover. Consequently, the trees will experience less stress, increasing their chances of recovering fast.

We Can Help

OurPlant Health Care (PHC) program uses organic methods to combat pests and illnesses in our gardens. While we can’t control tent caterpillars and other pests all year, we can keep the beneficial pollinators and predatory insects you want to see around your shrubs and trees all year. Please contact us at 908-309-6611 if you would want us to evaluate your trees for Eastern tent caterpillars or to propose a PHC program for your trees.

What Eats Tent Caterpillars?

A gigantic silk nest is constructed among the branches of trees by tent caterpillars. During the day, they leave the nest to eat on leaves, and they return to it at night to rest. They are protected from predators while in the nest, but after they leave the nest, they are preyed upon by a broad range of other creatures, including humans.

Bird Predators

Predators such as birds eat tent caterpillars as they are hatching from their eggs or when they are in the form of moths. Caterpillars are picked off the branches and leaves by songbirds. Tent caterpillars are eaten by a variety of birds, including robins, blue jays, red-winged blackbirds, and cardinals. In addition to ground dwelling birds such as wild turkeys picking off caterpillars when they crawl to the ground to pupate, the caterpillars themselves are preyed upon by a variety of predators.

Most of the time, birds devour them whole.

Insect Predators

Parasitic wasps attack both the egg and larval stages of the eastern and western tent caterpillars, causing them to die. Flesh flies prey on forest tent caterpillars, causing them to die. Depending on where the caterpillar eggs are laid, these parasites may lay eggs on the caterpillars themselves. As soon as the larvae hatch, they begin to devour the eggs or caterpillars from the inside out, as described above. Stink bugs, hornets, and yellow jackets are pests that attack many kinds of animals.

In addition to eating caterpillars directly by grasping them in their teeth, they also sting them and transport them back to their nests where they are devoured by the adults.

Mammal Predators

Caterpillars from tents are eaten by a few species of animals, including humans. While squirrels consume caterpillars that fall from tree branches, foxes and other large mammals (including white-footed mice and chipmunks) devour them as soon as they strike the ground, according to the National Wildlife Federation.

The caterpillars and the moths will both be eaten by bats. Some species consume both the caterpillar and the moth in their whole, while others just consume the caterpillar and leave the moth wings behind.

Reptile and Amphibian Predators

Tent caterpillars are preyed upon by a variety of reptiles, including Eastern box turtles, garter snakes, copperheads, and skinks. Snakes and lizards are capable of climbing into trees in order to hunt for tent caterpillars, and they have even been seen to inside tents. It is possible that they will be eaten by water turtles if they fall into water. The tent caterpillar moths are preyed upon by a diverse range of frogs, including the wood frog and the American toad, among others. Tent caterpillar moths and caterpillars are consumed in their whole by reptile and amphibian predators.

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