Bagworms Life Cycles – Everything You Need to Know About The Life of a Bag Worm

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Bagworms are not the ideal creature you want hanging from your garden trees. These bagworms can cause excessive damage to the trees, and it is not uncommon to find this happening. 

Yes, indeed, it is a very interesting-looking worm, which doesn’t look like a typical one, as it is covered in a bag-like structure. 

So, you might be wondering what bagworms are and how it grows into these ‘bags’? 

Well, that is precisely what we will discuss here.

From its life cycle to how you can control them, you’ll get to know all of this in our extensive guide. 

Interested? Let’s get started. 

What are Bagworms?

Bagworms are actually caterpillars who spend their entire lives inside a solid and secure ‘bag’ which is created with silk and is covered with foliage that makes up the perfect camouflage. 

Moreover, each of the bagworms builds their bag in which they live, feed, and eventually die. 

These caterpillars feed on the plants/trees; they survive on the leaves or needles of plants like Willow, Sycamore, Spruce, Maple, Oaks, Rose Plants, etc. 

If you find these worms on your tree, it is crucial to get rid of them as quickly as possible. They not only sabotage the plant severely, but can also kill them. 

The bags of these worms eventually expand as they constantly feed on the host tree. These can grow up to two inches in length over just one summer. 

Scientifically called Psychidae, the adult male of this species have wings of at least one inch. 

On the other hand, the female bagworms are primarily yellow and resemble a tiny caterpillar. 

The Life Cycle of Bagworms 

Like any other organism, the life cycle of the bagworms has various stages. To help you understand this better, we have compiled a simple, handy guide. 

  1. Mating 

First things first, to initiate the process of the life cycle and reproduce. The adult male and female worms mate with each other. 

Interestingly, the male dies right after mating outside its bag. After the females produce hundreds of eggs, they too die inside their bags. 

The eggs hatch around summer after they are fully grown and developed. 

The instant death of the adult bagworms after mating leads to producing only one generation of bagworms each year. 

  1. The Larvae Stage 

After these worms have hatched their way out of their eggs, the larva of this bagworm has a silk stand that helps it hang and even lets it find a host plant on which it can feed and survive. 

The moment this bagworm larvae finds a host to survive and feed on, these tiny creatures start to build the protective layer around themselves, and these bags grow in size with time. 

As well as this, these worms stay inside the tough bags their whole lives and only have their heads out to feed on the host. 

They also have their limbs poking out for some movement. 

  1. Pupa and Adult Stage 

These bagworms are harmful to your trees because they constantly feed on the leaves/needles of the plant until they have reached their maturity. 

They typically reach maturity around August. 

After this, it develops into a pupa, and therefore, it attaches its bags to a branch with a silk strand; this marks its growth into a pupa. 

The adult bagworm eventually develops from the pupa. The male worms look a lot like moths with fur and wings. However, the female does not have any wings. 

Throughout this process of growing and transforming, these worms never leave the protective bag. 

Once these bagworms reach their mating period, they mate and die right after. 

How Can You Control Bagworms Growing On Your Trees?

Okay, it is a possibility that you have seen these bagworms grow on your tree without doing any harm. 

So why blame these worms? Well, the thing is that if the development of the bagworms does not kill your tree, then the chances are that you have a deciduous plant (these plants shed their leaves once a year). 

Only a deciduous tree can withstand the attacks by bagworms, so if you have any other type of plant, and you spot a bagworm it’s best to get rid. (we explain our best methods in the next section) 

Besides choosing a deciduous plant to control bagworm damage, there isn’t much you can do to control the young larvae before they appear. 

These bagworms are generally a pest that feeds on the foliage of other types of trees, which leads to either extreme damage or death of the plant. 

Bagworms generally hang from trees, camouflaging themselves with the tree. 

It is recommended to get rid of these as soon as you can. 

How to Get Rid of Bagworms on Your Trees?

So you’ve spotted the notorious bagworm? Now it’s time to remove them. 

Their nests are typically brown or gray and resemble small pine cones. When you spot one, make plans to eliminate them.  

You can either choose chemical control or natural ways to get rid of these bagworms. 

Although it is better to use insecticides, you can even remove these manually or plant a daisy plant nearby. The parasitoids on the daisy plant will kill these bagworms. 

But if you want to get rid of these fast, then you must spray insecticides on these bagworms when they are still young larva. 

Around June or July is the best time to apply these insecticides, as if you spray them when bagworms are almost in their adult stage (August), then, of course, there will be less effective or not effective at all. 


In this extensive blog, you got to know all about bagworms. 

These caterpillars stay inside a protective structure all their lives and feed on host plants/trees for their survival and development. 

These worms go through a long development process, from eggs to finding an ideal host plant.

On top of this, when these bagworms grow into adult male/female worms, they mate to produce the next generation and die right after the process of mating. 

Therefore, you must take precautions and measures to control these bagworms from growing into your garden as they can destroy the plants. 

Now that you know all about these, you can go right ahead and protect your garden from them.