Yellow Caterpillars with Identification Guide and Pictures

As spring approaches, gardens become a host to multiple leaf-eaters, like caterpillars and larvae. If you see newly nibbled holes in the leaves of your plant, there are high chances that it is attacked by a caterpillar.

The yellow fuzzy caterpillar is a cute and pretty harmless creature. It eventually turns into a butterfly or a moth. But they also leave plants dying. Here is everything you need to know about yellow caterpillars.

Having said that, we don’t mean to invalidate the place of a caterpillar in the ecosystem. They are a food source for other animals and become important pollinators when they grow up.

A celebrated caterpillar that turns into a monarch butterfly is reared in special cages. But gardeners don’t usually tolerate them as they can easily spoil a season’s worth of hard work.

What Are Yellow Caterpillars?

After hatching from an egg, caterpillars create a cocoon from themselves. It becomes a butterfly after hibernating inside the cocoon after some time.

Caterpillars have an elongated body and a hard head capsule. They have six legs, although it seems like they have more. They vary widely in colors, patterns and shapes. They can have spots or stripes. It measures from ¼ inch to 1 inch in length.

Caterpillars have a unique way of moving. If you notice carefully, it elongates its body and then scrunches it up into a bend. It keeps repeating this process to progress.

Yellow fuzzy caterpillar is of five types and is found in North America. They can be distinguished according to the density of fur across their body. The shades of yellow may also differ.

Furry, Yellow, White-Masked Tussock Moth Caterpillar

You can easily identify this vibrant creature. It has long brown hairs, a yellow body, and long antenna-like hairs on the front and back with some white poofs at the back.

Mature caterpillars have a bright red head and a handful of white tufts of hair on top. The reason why we are specially mentioning this caterpillar here is that you should not touch them.

They have stinging hair, and they can puncture the skin causing hives and rashes on humans that have sensitive skin.

Common Caterpillars Found in Fall

Caterpillars that appear in the fall are fuzzy yellow or white caterpillars. They look inviting from a distance as they are of vibrant colors with protruding tufts of hair. Generally, you should avoid touching any unknown insect no matter how appealing it seems because there are potential risks of stings and irritation.

During spring and summer, plant growth rises. As sunlight is strong and remains for a longer period of time, photosynthesis is at its peak. Deciduous plants are capable of withstanding almost 40% of defoliation with no ill effects, therefore, caterpillars feeding them during this time of the year does not really do a lot of harm.

But, during fall the growth slows down. Fruits fill out and new growth halts plants start preparing for winter. In a few weeks, leaves will drop off and no greenery would be left.

Identifying fuzzy yellow caterpillars is a difficult task as they are of different varieties and you cannot identify them with the help of tufts, because they may break off naturally or as a part of the caterpillar’s defense mechanism.

Common Fuzzy Yellow Caterpillars

Since we are particularly talking about the yellow-colored little creatures, let us see some common yellow caterpillars that you may across while roaming in your garden:

The Yellow Woolly Bear

The Yellow Woolly Bear

Out of all North American caterpillars, the yellow woolly bear caterpillars are the most common ones. They are fluffy-looking with long and thin hair. The fuzzy hair color can range from white to yellow to reddish-brown.

These caterpillars can be identified through their short bristles and extra-long hairs. The woolly bear fuzzy caterpillar is not poisonous, but they are very irritating for the skin.

These caterpillars love carrots, eggplant and sweet potato leaves so you will frequently see them munching on these plants. Always make sure you wear protective gloves if you are trying to get rid of these.

After going through a metamorphosis, these caterpillars turn into the Virginia tiger moth. The Tiger moth is a beautiful white creature.

Buff-Tip Moth Caterpillar

Buff-Tip Moth Caterpillar

This black, yellow caterpillar feeds on oak leaves. They can grow up to 70mm long, and have long hairs that can cause irritation to human skin. This fuzzy yellow caterpillar hatches from the egg cluster.

The larvae feed together until they grow up to larger sizes. The caterpillar usually grows fully in 30 days. You will find these caterpillars between early July and October.

Sycamore Tussock Caterpillar

Sycamore Tussock Caterpillar

Commonly found in some parts of the United States, they usually wander around finding a safe spot for making a cocoon.

These caterpillars do not sting but the hairs may cause irritation to the skin. They do not cause serious damage to plants, unless they are in enough numbers. The species is not rare. The caterpillar turns into a beautiful pale-brown tiger moth.

These caterpillars occasionally drop from the leaves and feed on walkers. These are commonly found from July to September.

Cinnabar Moth Caterpillar

Cinnabar Moth Caterpillar

Growing up to 28mm long, the cinnabar moth caterpillar looks as if it is wearing an ugly black-yellow striped shirt. The caterpillar is vibrant and hard to miss. The stripes are there for a reason, stripes in any insect warn the predators of a creature’s unpleasant taste. You will find this caterpillar in the month of July to September. They are usually seen in open grasslands and heathland.

Monarch Butterfly Caterpillar

As spring approaches, female monarchs begin laying their eggs, especially on milkweed. These caterpillars have yellow-black stripes and are said to engulf toxins that may harm predators. After caterpillars grow up, they attach themselves to a leaf or a stem and transform into an amazing butterfly. They are found in the USA, Australia, India and Europe.

Monarch caterpillars are known to chew milkweeds – lots of them. They do it not just to feed themselves but also for protection, the milky sap from the leaves stays with them even after metamorphosis and makes the adult butterfly taste awful to the predators.

Since these caterpillars only eat milkweed, they are not a threat to the garden. In fact, gardeners all over the world always try to attract them. Farms that allow milkweed to grow around the fences are a good breeding spot for these caterpillars.

Southern Flannel Moth Caterpillars

Southern Flannel Moth Caterpillars

This yellow fuzzy caterpillar is very attractive and unique. It looks just like a fluffy ball with soft hair all over its body. You will be tempted to touch it, but please don’t. The puss caterpillar is one of the most poisonous caterpillars out there. Under that soft fur, there are toxic spines that stick to the skin. The pain after touching this yellow fuzzy caterpillar can be more than the pain after a bee sting.

You may experience several symptoms like headache, fever, nausea, and respiratory diseases. The sting becomes even worse as the caterpillar grows. These caterpillars eventually turn into furry yellow-orange moths.

The caterpillar looks very ‘cute’ and thus it attracts children. They always want to pick it up. The spines underneath the yellow fuzzy caterpillar sting very hard. The venom can cause throbbing pain and red spots. Most species are found around shade trees, ornamental shrubs, fruit trees, etc.

American Dagger Moth Caterpillar

American Dagger Moth Caterpillar

Another yellow fuzzy caterpillar, the dagger moth caterpillar has irritating fur around it that spins around the cocoon. The black hair antenna makes the caterpillar look more threatening than it really is. They are commonly found in late summer and early fall. It feeds on trees like oak, ash, birch, elm and maple. It causes no damage to the plants. It eventually turns into a beautiful gray moth.

Spicebush Swallowtail Caterpillar

Spicebush Swallowtail Caterpillar

This is one of the coolest caterpillars found around us. The most unique feature it has is its eyes. The eyes look exactly like a snake, which makes the insect intimidating to look at. It also has another feature called ‘osmeteria’, which is a red and forked organ.

It is located behind the head and the caterpillar sticks it out when it is bothered. The osmeteria looks like a snake’s forked tongue and smell terrible.

The caterpillar can be found commonly everywhere except northern states. It does not cause serious damage to plants. It looks dangerous but doesn’t sting. It turns into a beautiful spicebush swallowtail butterfly.

The Magpie Moth Caterpillar

The Magpie Moth Caterpillar

This species of moth is a favorite among collectors that breed it to obtain unusual and colorful patterns. You will find them in parks and gardens. The color and pattern of the magpie moth are similar – black and yellow spots. The caterpillar is common as a garden pest. 

The Large White Caterpillar

The Large White Caterpillar

This fuzzy pale yellow-green caterpillar turns into a large white butterfly, hence the name. It also has striking black spots and visible hairs on the body. The bold appearance is a warning to the predators of its unpleasant taste.

The body of the caterpillar is poisonous due to the mustard gas its body accumulates. Due to its love for cabbage, it is also called the ‘cabbage’ white caterpillar. It is famously known for chopping off cabbages, leaving barely anything behind. They can be found across the United Kingdom, between March to October.

Saltmarsh Caterpillar

They are 5.5 cm long and can be found feeding on various vegetables like beans, cabbage, corn, tomato, cotton, and soybean. They can also be found in weeds. They are found in the USA, especially in regions around Central America and Canada.

They have dark, rusty coloration – with a pinch of yellow shade. It has medium bristles and tiny black spots. This caterpillar looks a lot like the yellow fuzzy woolly bear caterpillar, the only difference being black spots all over its body.

They are also of a darker color than the woolly bear. The fur of these caterpillars is irritating, and may give you an itchy rash. They spin an orange cocoon and turn into a really beautiful, pale orange butterfly.

Fuzzy and Hairy Caterpillars

Like the yellow fuzzy caterpillar, we talked about till now, there is something special about caterpillars with hair. When the larvae are in the premature stage, it has white hairs growing from the body.

Although the hair color may differ, it is usually white initially. These caterpillars feed on tree and plant leaves, and eventually defoliate them. They may also have a single tuft in the head and another in the anal region.

The larvae then pupate in a cocoon of hairs or leaves or branches. If you want to get rid of them, consider an integrated approach with preventive measures. Insecticides like deltamethrin work well with hairy caterpillars. You should regularly monitor your orchard for eggs, larvae, moths and cocoon.

Poisonous Hairy Caterpillars

Fuzzy caterpillars are a treat for the eyes. But not for the body. Caterpillars are defenseless and high in protein. This is the reason why they are loved by predators. So, caterpillars have evolved various means of protection.

The markings on their body are a sign of how dangerous they are. Some of them are even poisonous, to consume and to touch. Some hairy caterpillars like the yellow fuzzy ones we talked about that are poisonous are described below:

Saddleback Caterpillar

Native to the United States, the beautiful saddleback caterpillar can be identified by its saddle-shaped spot on the back. It is also called slug caterpillar because of its short length and abdominal legs. You need to make sure you don’t touch the attractive pompoms on their heads. They have hair that secretes venom. The sting can be extremely painful and pain can last for several days.

Giant Silkworm Moth Caterpillar

Giant Silkworm Moth Caterpillar

This one looks as scary as it is. This is not a caterpillar you would want to meet, especially in a dark space. Also known as ‘assassin caterpillar’, it is responsible for almost 1,000 deaths from 1997 to 2005 in South America.

The caterpillar has many spear-like bristles that penetrate the skin and injects a venom that leads to headache, fever, vomiting and malaise. After these symptoms, you may experience severe bleeding that may lead to acute renal failure or hemorrhages.

Types of Hair in Caterpillars

Caterpillar hair can be categorized into two types: urticating and stinging. Stinging hairs are like hollow spines with cells that secrete poison. The poison causes systematic effects after they enter the skin and break off. Urticating hairs are itchy and non-venomous and cause skin irritation.

Itchy, Fuzzy Caterpillars: Symptoms, Diagnosis, Treatment

Symptoms

Symptoms from being in contact with fuzzy yellow and other itchy caterpillars include instant pain with a long-lasting ache. If you contact a venomous caterpillar, symptoms will include extreme itch followed by irritating rash and burning sensation.

Other symptoms are dermatitis, itching, pain and swelling. The intensity of this irritation will vary as per the species of the caterpillar. If detached hair is inhaled, it may cause labored breathing which may last for many days. Many people have also reported eye injury and may lead to conjunctivitis.

Treatment and Control

Fuzzy caterpillars can be dangerous. After reading this article, if you ever come across a caterpillar and happen to touch it, you will be scared of what it can do to you. Please remember that caterpillars are not that dangerous, and you will suffer only if you touch, poke, or threaten them.

Always avoid touching any hairy caterpillars and places that they have been in touch with. If you are a gardener or someone who needs to touch it, make sure you wear protective gear like eyewear and gloves.

The infections are short-lived and subside after a short period. For plants, a pest control officer can chemically treat the plant or tree infected by the caterpillar. Infestations will die out through the depletion of food resources or predation.

Treatment of itchy skin includes removal of all affected clothing. A good method can be applying adhesive tape in the affected area and pull the tape off immediately. This will remove the majority of hair and reduce irritation. The tape can later be examined under a microscope.

Make sure you wash all areas where the hairy caterpillar has been observed or where irritation occurs. Usually, irritation occurs from touching a caterpillar or moth. It can also be caused by contact with bed linen after moths or airborne irritating hairs that have landed on washing.

You will usually find stinging caterpillars on food plants and direct contact with the caterpillar causes the sting. The best kind of remedy is to recognize food plants and avoid touching them during their growing period. Ice packs, creams and lotions may assist in relieving the symptoms of reactions.

Getting Rid of Fuzzy Caterpillars

To get rid of itchy and fuzzy caterpillars, there are three methods. One is to remove the caterpillar manually with hands. As mentioned earlier, wear gloves and eyewear and pick them from leaves. Put them in hot water to kill them.

The second method can be more effective. It is finding out caterpillar nest eggs and destroy them. The nests are spun, silk-like sacs that can hang in trees and cling to leaves.

If these methods don’t work, the affected plants can be treated with Bacillus thuringiensis (BT). It is a bacterium that occurs naturally in the soil. When a caterpillar eats BT, the bacteria destroy its stomach lining causing the caterpillar to starve and die.

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