Intriguing Facts About Inchworms You Probably Didn't Know

Fact about inchworms
Many of you may have come across inchworms in your garden. However, these small creatures have many interesting facts that are worth knowing.
Did You Know?
There is an exercise called 'inchworm'! It is called so because it involves an up and down motion similar to that of an inchworm on a flat surface.
Inchworms aren't worms, but are actually caterpillars that belong to the Geometridae family of moths. This family is of the order Lepidoptera and is known to have about 35000 different species in the world. Furthermore, about 1,400 kinds of geometer moths are known to live in North America. These caterpillars are also referred to as loopers, spanners, or measuring worms.
Here, we give you the many interesting facts about inchworms that will help you know about their peculiar movement, the reason behind their unusual name, and other attributes like their appearance, habitat, eating habits, life cycle, and more.
Appearance
▸ These caterpillars are small, hairless, and have fewer legs as compared to other species.
▸ They are about 1-inch in length and can be green, brownish, gray, or black in color. This usually depends on the type of moth they would become.
▸ Some of them are also known to have black spots on their head.
▸ Their legs are located only on the front and back portions of their body.
Brown Inchworm
Inchworms in two different colors
Gray Inchworm
Locomotion
▸ The term Geometridae is believed to have come from a Greek word meaning 'earth-measurer'. This meaning can be applied to the peculiar movement that inchworms have.
▸ Since they have no legs in the middle portion of their body, they need to pull their hind portion forward forming a loop, and then move forward with the front portion of their body.
Inchworm Locomotion
The peculiar movements of an inchworm in locomotion
Inchworm Locomotion Loop
Habitat
▸ They are usually found in regions with a temperate climate.
▸ They are said to live in areas near their food sources like oaks, lindens, elms, maple, apple, and other fruit trees.
Defense Mechanism
▸ They are believed to be hunted or preyed on by some types of birds, lizards, and wasps.
▸ On sensing a possible predator, they become still and resemble a twig.
▸ They bear markings that appear like those on barks or leaf scars. They have the ability to camouflage in order to stay protected from predators.
▸ They are known to produce silk that they hang from. In case of danger, they drop quickly from the leaves they feed on and hang from the end of the silken strand. Once its safe, they get back up and continue eating.
Eating Habits
▸ A single inchworm does not eat much. However, it is said that a large hungry group of inchworms can cause serious damage to trees and bushes, like those of apple and mulberry, and most garden plants.
▸ Most of their species are believed to feed on leaves of deciduous or coniferous trees. However, there are some that eat lichen, flowers, or pollen.
▸ Furthermore, there are some such as the Hawaiian species (of genus Eupithecia) that belong to the carnivorous group as well.
▸ Cankerworms are a species of inchworm that are believed to be destructive and are also considered as pests by farmers and gardeners. A pathogen named Bacillus thuringiensis is used to treat infestations caused by them.
Life Cycle
▸ Inchworms are generally believed to have a lifespan of one year.
▸ They are known to grow into an adult geometer moth.
▸ The size of such an adult moth ranges from 3/8 of an inch to 2 inches from one wing tip to the other.
▸ The male moths are known to have a wingspan of about an inch whereas the female moths are wingless.
Geometer Moth
A geometer moth
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▸ Adult geometer moths are considered similar to butterflies in the way they keep their wings erect on landing, which is not the case with many other moths.
▸ They are generally said to be active during the night. However, there are some species that are active during the day as well.
During winter, adult moths are known to lay large clusters of gray, cylindrical eggs on the branches of trees. In this way, one generation in each of their species is born annually. The eggs hatch in spring. Once hatched, the larvae feed on leaves till it is time for them to develop into pupa. This feeding on leaves would be around 5 weeks. They then spin silken cocoons and go below the ground encased in it, until they emerge as fully grown adults.