caterpillar vs worm; what is the worm; what is the caterpillar

Caterpillar Vs Worm

From a very normal perspective, it’s tough to tell the differences between a caterpillar vs worm. If you don’t know the basics, they will seem similar.

But they are not the same. This article will identify the basic differences and similarities between caterpillars and worms. It will be an enlightening journey. 

Also, at the end of the write-up, I will suggest ways you can get rid of worms and caterpillars if they are causing trouble to your garden or backyard.

Difference and Similarities of Caterpillar Vs. Worm





Insect larvae stage of different species of the Lepidoptera family

Type of animals that have a long and cylindrical body


Caterpillars have 6 pail of eyes

No eyes


Can understand the sunlight

No vision


5-6 pairs of prolegs

No legs


Using 5-6 pairs of legs and abdominal muscle 

No limbs, moves by the help of muscles

Food type

Vegetation and plants

Vegetation and blood and waste of animals

Digestive System

Well-developed mandibles with sharp teeth like surface that can cut leaf surface

No complex digestive system

Parasitic Nature

Caterpillars live in the exterior part of the host

Many worms reside in human and other animals

Life Stage

2nd stage of insect development

Adult stage of development


15 to 30 days

From 4 to 8 years

Blood type

Cold blooded

Cold blooded

Places Found

Host bodies, Marine environment, underground

Vegetation and host plants

What Is the Caterpillar?

The caterpillar is an insect, specifically the larval stage of Lepidoptera. That means a caterpillar stage is a potential moth or a butterfly depending on the type of the caterpillar.

One of the 10 caterpillar facts is that a caterpillar only is alive for 15 to 29 days before it can turn into a butterfly or a moth. It can cause serious issues to food plants, agriculture, and your favorite plants within the lifespan.

On the contrary, there are a few benefits of caterpillars. Different caterpillars can produce silk; some can do pest control in fields, etc. 

Caterpillars can grow fast. The size of a caterpillar can be between 1cm to 14 cm. They have about 10 to 12 eyes, half of them on each side of their head. The weight of a caterpillar insect is 3 grams only.

Their legs can be two types:

  • Prolegs – These 5 pairs of legs are used for climbing up on a vertical surface. 5 pairs of these prolegs are adjacent to the abdomen, and one leg is at the back end. It’s called anal proleg.
  • Thoracic Legs – These 3 pairs are used for holding onto their food.
Is caterpillar an insect or worm?; do caterpillars have teeth; are green caterpillars poisonous to humans

What Is the Worm?

The worm is a long and cylindrical animal that looks like a tube. It has no limbs, no eyes but can understand when it’s sunny outside. The size of worms is variable. Some worms live in animal bodies like parasites are microscopic inside. 

And on the other hand, this giant African worm is sized up to 6.7 meters, and the bootlace worm that’s 58 meters. No matter how long these worms are, they have no defense mechanism.

So, they are often devoured by leeches, snails, and other animals without resistance. The only thing a worm can do, which almost no other animal can, is reform and regrow parts of its body as before. 

They can live 8 years at best. But in these 8 years, they can cause much damage to plants and different animals. Some worms live in damp areas, and they suck the blood from other animals’ bodies.

african giant worm; grass root eating worms; 10 caterpillar facts

What Problems Do Worms and Caterpillars Cause?

The main source of food for a caterpillar is leaves. They eat leaves that are healthy and green. This eating habit alone can cause a lot of problems. 

Some plants can fight off caterpillars if they have some biological protection. In most cases, it’s a very rare thing to happen.

Certain worms live on vegetation and plants. These worms can not only harm the plants by eating the leaves; the underground worms can destroy the roots of plants. 

If your garden is affected by a worm or a caterpillar infestation, you need to take strict action to get rid of them. The best way is to apply pesticides. Yes, pesticides cause harm to plants, but if not applied, there will be no plants left to save.

What We Suggest

There are many pesticides available for worms and caterpillars. But pesticides can be harmful to plants, fruits, and vegetables. You need to pick certain pesticides that don’t cause harm to the plants.

Monterey LG6332 Bacillus Thuringiensis

The Monterey LG6332 is a great pesticide that can eliminate both caterpillars and worms. It can destroy bagworms, cabbageworm, woolly worms, tomato hornworms, fuzzy caterpillars, fall cankerworm gypsy moths, and elm spanworms. That’s a lot of insects to take care of.

The best part of this pesticide is that it only kills what it’s supposed to. It doesn’t affect birds or other animals that help the germination of plants. The pesticide is approved for organic gardening so you can use this in your organic garden.

Bonide BND806 Caterpillar and Worm Killer

The Bonide BND806 is one of the best pesticides you can go for. It comes in a spray bottle and is ready to be sprayed on directly without the necessity of dilution. It can kill everything that can be killed by the other pesticide and kills cabbage looper, woolly bear caterpillar, green caterpillar, black caterpillars, hairy caterpillar, tent caterpillar, and hornworms.

It is only capable of killing insects that are harmful to the plants and leaving the ones fighting the infestation with biological control of beneficial insects. For instance, you will see that there are still ladybugs and bees on your plants even after spraying the pesticide.

Final Words

I hope I have covered everything you have to know about the comparison of caterpillar vs. worm. If you have read the description and the differences carefully, you will be able to tell the difference between them.

Most importantly, whenever you see that your garden is getting infested by worms or caterpillars, grab one of the above-suggested pesticides and end the infestation before it can increase and cause problems to the harvest.

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Robert Silver

Robert Silver is a writer, speaker and certified master gardener who has been sharing his landscaping experiences through personal blogs. Taking it to the next level, Robert Silver has come up with this to shine a light on new planters and experts, discussing plants, landscape projects and much more. He has published numerous research articles on horticulture that have helped many people attain fruitful outcomes.