Earthworms are present in both poor and rich soils. However, earthworms are more often seen in rich soil where they can find more nutritional ingredients that encourage their growth and development. Different types of earthworms can be categorized based on their traits but also the different species that they belong to. Although all earthworms may look the same to you, you’ll be surprised to see how many types of earthworms species there are.
We wrote this article that will help you understand and recognize different types of earthworms.
There are thousands of different worm species, and not all of them are considered earthworms. Still, those that we may occasionally see on the side road, in our garden, or lurking around our house are also known as earthworms.
Recognizing that a worm you see is an earthworm is fairly easy. However, recognizing which species it is more difficult for most people.
Don’t worry, if you continue reading this article, you’ll be able to classify the earthworms based on their category. You will also be able to identify the species if you see it often enough in your garden.
What Are Earthworms?
There are many different types of worms in the world, lurking beneath the soil, inside some animals, trees, or under rocks. Needless to say, it can be quite difficult to tell the difference between earthworms and other types of worms.
With over one million species, the difficulty increases as the list of newly-discovered species is added. But, let’s properly define earthworms. Just like other worms there are, earthworms can be recognized as tube-shaped. They’re commonly found in the soil.
It’s also worth mentioning that earthworms are segmented, which means they consist of different sections. They’re not picky eaters. They nibble on any kind of organic matter in the soil. Being segmented, the entire digestive system runs through the body.
You may wonder what exactly organic matter entails. Their food can include anything from dirt that in the soil they live in, to eating the leftovers of fallen leaves and other natural litter.
Because they don’t have a respiratory system like other, more developed animals, earthworms can breathe through their skin, which is also how they get rid of toxins.
What makes earthworms fascinating animals is that they are capable of having two roles in terms of their reproduction system. They can release eggs and sperm, which means they are classed as both biological sexes.
Earthworms need to tightly attach their bodies to one another. Once they’re done exchanging sperm they go their separate ways. It’s however, important to note that the reproduction process takes place on the surface of the earth.
While some earthworms barely grow past half of an inch, some can grow up to 14 inches in length. In some areas with an adequate climate that promotes their growth, they can grow anywhere from 5 to 10 feet in length.
You’d be surprised to know how many worms there are, but first, it’s necessary to learn about the three main categories:
Main Types of Earthworms
Based on these three main categories, you’ll be able to recognize all types of earthworms that fall into those categories.
Each type of earthworm is important to the ecosystem it inhabits, studies show. This will also help you learn more about your soil, and the environment you live in.
Endogeic earthworms were named after an ancient Greek term which means “within the earth.” Their name represents the way they live and dwell in the Earth. They rarely go above the surface and prefer spending most of their time buried within the top levels of the soil.
Thanks to the composition of the topsoil layers, they can make horizontal burrows that they live in until they migrate to other location within the soil. Sometimes, they will also hide under the rocks and logs lying on the soil.
On rare occasions, some of them dwell even deeper beneath the Earth until it rains. When it rains, they’re encouraged to go out of their burrow and collect some of the rain as rain promotes their health and prevents them from drying out due to lack of moisture.
- They’re quite small compared to other types of earthworms, they will usually measure from 1 to 12 inches.
- They rarely appear above the surface and like to make burrows in the top layers of the soil. However, they do like to go out in the rain and grab some extra moisture.
- You’ll easily recognize them because they’re pale white and usually translucent, as they don’t have a pigment that could give them color. Sometimes, they can come in pale gray, green, blue, or pink colors.
- They’re slow travellers, compared to other types of earthworms they move significantly slower.
- They’re helpful when it comes to aeration, which contributes to mixing minerals and air within the soil.
- They are not picky eaters and mostly feed on soil.
- They make horizontal burrows, unlike other worms that make vertical ones. They’re only semi-permanent burrows, however.
Unlike the endogeic worms that are famed for building horizontal burrows, epigeic earthworms appear above the earth and spend most of their lives there, hiding and resting in the organic matter that has started the decaying process.
There are other names for this type of earthworms, sometimes they’re called surface-dwelling earthworms, as well as compost earthworms, which are all appropriate translations for their original Greek names. Most commonly they can be found among the leaves or compost heaps.
They prefer to stay surrounded by a lot of organic waste on which they can feed and use for protection from predators. Living in dark-colored, decaying leaves also helps camouflage them because they have a dark coloring that prevents them from being seen easily. They adapted to life above the surface with dark pigment that protects them from strong UV rays.
- Thanks to their strong muscles they can move much faster than other worms in this list.
- Dark pigmentation not only protects them from predators, but it also gives good protection when it comes to UV exposures.
- Play a great role in composting, especially because they help break material down quickly.
- One of their main traits is that they can reproduce quickly, compared to other species.
- They’re smaller worms with sizes from half an inch to 7 inches
- They mostly live among leaves and compost heaps.
- The epigeic worms don’t make burrows but spend most of their lives on the surface.
We believe that Anecic earthworms take the best of both worlds. They can be found living deep below the soil. However, whenever they get hungry, they’ll dwell in the top soil level or above the ground in search of nutrients that will help them thrive.
So, while endogeic earthworms create horizontal burrows, anecic earthworms are famed for making vertical burrows that can travel deep within the soil. Their burrows usually reach up to the top layers of the soil which are richer in minerals that they need to feed on.
Unlike endogeic earthworms, these worms create burrows that are mainly permanent. Sometimes, their burrows can reach down to 6 feet underground. Their burrows are quite big and wide, which is likely why they’re considered permanent.
It’s worth noting that they feed similarly to the endogeic earthworms. As they have to stretch above the ground to feed, they’ll eat organic waste, but mostly leaves that have fallen off the trees. They are also quite strong, which allows them to drag the collected leaves deep into their burrows where they create food stacks. You’ll also find them eating soil and organic litter as part of their diet, but they’re most known for grabbing the leaves off the ground.
- They create vertical burrows that run deep underground.
- They, however, climb up to eat leaves, soil, and litter, as well as other organic compounds.
- Anecic earthworms are the most common types of earthworms. Even though they are buried within the ground, they’re commonly used for baits and nightcrawlers.
- They’re the slowest-moving earthworms, even slower than endogeic earthworms.
- Their sizes are different, they can start at one inch and grow as big as 15 inches.
- Although they’re not completely colorless like the first of the mentioned earthworms, they have some weak pigment that helps people distinguish between different types of earthworms. But it’s mostly their size that helps identification.
Other Groups & Species of Earthworms
Compost worms can be found living above the surface or the first few inches under the surface. You’re unlikely to see them dwell deep. They’re commonly found in the garden soil.
They build small, temporary burrows among the top levels of the soil and mostly around the bacteria and fungi, and they commonly feed on leaves and vegetable organic matter. They’re also known to hibernate so they can keep their energy levels optimal.
They’re not particularly fond of extreme weather conditions. They’re more likely to hibernate in the hot or cold months of the year and do their best to keep themselves moist.
Earthworker worms are commonly found in your garden, be it a floral, fruit, or vegetable garden. They are known for digging holes and building burrows deep underground, and only coming out to eat. They are not picky eaters so they will likely eat leaves and other compost material, but will eat soil too. They are nocturnal when it comes to feeding and you’ll rarely see them during the day.
Gray earthworms can be found anywhere around the world – they’re considered one of the most abundant types of earthworm. Still, it can be most commonly found in the United Kingdom. It doesn’t live hidden deep into the soil, but usually on top of it where it feeds and reproduces. It has a special color that is often different shades depending on the segment. This type of worm feeds on leaves and other organic matter in its surroundings.
Brandling worms are true surface dwellers. They are most abundant close to plants in the garden. They’ll avoid diving into the deep layers of soil, unless they have to protect themselves for some reason.
Other than organic waste, they’ll also feed on different vegetation, compost, and occasionally, manure. One of the most important traits of brandling worms is that they have strong muscles that allow them to move swiftly. This trait is an important asset when it comes to escaping predators.
You won’t have difficulties recognizing this earthworm. Its segments are equipped with special structures that closely resemble bristles which help them move fast.
The green worm is abundant in Europe. However, it’s most commonly found in the UK, where it makes up around 35% of all earthworms. Just like its name suggests it’s green thanks to a pigment called bilin. It’s worth noting there are exceptions where these types of worms have bright pink coloration instead.
These worms aren’t large – 2-inches is the average length for adults. They also come equipped with special discs that help them drag food or suck food towards them.
Although they are widespread around the world thanks to plant transportation (and are commonly used as fishing bait), common earthworms are most abundant in Western Europe. Their favorite food is leaves upon which they like to spend most of their time feeding and hiding from the predators.
Like other agile and mobile earthworms, the common earthworm is packed with strong muscles that allow them to move effortlessly and drag food with them as well as evading their numerous predators from birds to foxes.
It can be hard to distinguish between them and other worms, but a red-brown pigmentation may help you with identification.
Red-head worms are common earthworms that sport red-purple pigmentation and are common in different parts of the world. However, it’s not a commonly desired worm to have in your garden. At first, it may be hard to spot because it burrows itself in the upper top layers of the soil.
Its specific habits when it comes to feeding might anger gardeners who want to see their plants thrive healthy and big.
According to ecologists, this type of worm represents a big threat for different ecosystems and communities no matter where it is in the world, as it may compromise the health of the plants you’re growing. It can grow from 4 to 6 inches in length by the time it reaches adulthood.
As their name suggests, these types of worms can bury themselves very deep into the soil, creating vertical burrows where they’ll spend most of their life. They’re abundant in various places in the world, and burrow deep enough to reach the roots of trees and plants. It will eat soil, but it’ll also go out above the soil to feed, mostly nocturnally.
They are quite rare, so if you think they’re hard to find it’s likely that they’re not even in the garden.
Eiseniella tetraedra is a small worm that can grow from 2 to 4 inches in length by the time it reaches adulthood. It’s recognizable thanks to its red pigment. You likely won’t notice them in your garden unless you live near a lake or a marsh as they are aquatic.
They can commonly be found in the mud or under some rocks that are located near or in the water. They feed on various organic waste that they can find, they’ll also feed on mud.
Giant Gippsland Earthworm
Remember when we talked about earthworms which can grow extremely large thanks to the conditions they’re in? Well, the giant Gippsland earthworm is one of them. It’s one of the largest worms in the world, in fact, and it lives in Australia. That shouldn’t surprise you given how many giant spiders, reptiles and other creepy crawlies can be found there.
Its pigment is usually pink-grey but some segments can be dark purple, or almost black. When it comes to their colossal length, they can grow anywhere from 30 to 50 inches long. It prefers moist areas. It’s not exactly aquatic, but it can be found near rivers in deep soil that is moist thanks to the water nearby. They will only ever go above the soil to feed.
Although it’s native to Western Africa, thanks to the warming planet the African Nightcrawler can be seen more and more commonly around the tropical areas of the world. It needs to be constantly moist, which is why you’ll easily notice it thanks to its characteristic gloss.
It usually resides in places where the temperature is around 80 degrees Fahrenheit. It’s especially popular with composting because it’s capable of rapidly processing organic matter which helps deal with natural waste.