Yellow Caterpillars: Discovering The Animal Life

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, chances are they’ve been attacked by caterpillars.  The cute fuzzy caterpillars transform into butterflies or moths and become pollinators. A celebrated caterpillar that turns into a monarch butterfly is reared in special cages. There is so much more to to these yellow caterpillars you and I don’t know about. What’s there to know, you ask? Let’s see.

Yellow Caterpillars: Story Time About Who They Are

After hatching from an egg, caterpillars create a cocoon for hibernation and then transform into a butterfly. Caterpillars have an elongated body that include 6 legs and a hard head capsule. They come in all kinds of patterns, shapes and colours and are  ¼ inch to 1 inch in length. If you’ve noticed, caterpillars have a unique way of moving with their elongated body. They often scrunch into a bend and keep repeating this process to progress. There are 5 types of yellow caterpillar that can be distinguished according to the thickness of the fur on their body.

Furry, Yellow, White-Masked Tussock Moth Caterpillar

The vibrant creature has long brown hair, yellow body and long antenna like hair on the front and back with white poofs at the back. Most adult caterpillars have a bright red head and white tuffs of hair on the top.  They have stinging hair that can puncture the skin causing hives and rashes.

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. Plants are known to do really well during the summer and spring with direct sunlight and photosynthesis is at its peak. Deciduous plants are capable of withstanding almost 40% of defoliation with no ill effects.  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 can cause skin irritation. These caterpillars love carrots, eggplant and sweet potato leaves, and so they will be seen 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 stunning Virginia tiger moth.

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 and become full grown in 30 days.  They are often seen between July and October.

Sycamore Tussock Caterpillar


Sycamore Tussock Caterpillar are often wandering around looking for a safe spot to make a cocoon in most parts of the United States. These caterpillars do not sting but the hairs may cause irritation to the skin.

After hibernation, this caterpillar becomes a beautiful pale-brown tiger moth. These caterpillars occasionally drop from the leaves and feed on walkers. These are seen in the months of July and 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. 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

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 scarier than it actually 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

One of the most unique features of the spice brush swallowtail caterpillar is its eyes as they look exactly like a snake.  It also has another feature called ‘osmeteria’, which is a red and forked organ, located behind the head.  The osmeteria looks like a snake’s forked tongue and smell terrible. The caterpillar can be found commonly everywhere except northern states. 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 has striking black spots and visible hairs on the body that offers a bold appearance, a warning to the predators. 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 and 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 are found in the USA, especially in regions around Central America and Canada.

They have dark, rusty coloration with 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. The fur of these caterpillars  causes skin irritation which will lead to a 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 Caterpillar

Fuzzy caterpillars may be an absolute treat for the eyes, but not for the body. They are highly poisonous to consume and touch. The markings on their body are a sign of how dangerous they are. Wondering how and why? Let’s give you a glimpse of how dangerous they can be.

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. Their 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

Giant Silkworm Moth Caterpillar, also called assassin caterpillars are not the caterpillars you would want to touch, as they are scary and dangerous. The caterpillar has several spear-like bristles that penetrate the skin and injects a venom that leads to headache, fever, vomiting and malaise.  These symptoms lead to severe bleeding that may lead to acute renal failure or haemorrhages.

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 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. 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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