Garden Guide

Earthworms beneficial for health of land
Oct. 09, 2013 @ 05:02 AM

Earthworms are friendly creepy-crawlies that dwell deep within our soil. Besides being excellent bait for those who like to fish, earthworms are extremely beneficial for the health of the land. 

There are thousands of different species of earthworms in the world, ranging in size from quite small to over a meter in length (think of the fish you’d catch with that one!). In North Carolina we have a few different species of worms including the nightcrawler and the manure worm (red wigglers).

Worms feed on organic matter from the surface, such as grass clippings and thatch in your lawn. Earthworms do not have teeth; instead they have a gizzard that grids their food. Their excrement is called worm castings and is highly beneficial to the soil since it is full of beneficial microorganisms and nutrients. 

Most earthworms are found in the top six inches of soil; however, some tunnels may extend up to six feet deep, thus working the subsoil. In burrowing through the soil, earthworms aerate the soil, allowing oxygen into the soil. The tunnels also help with water penetration, decreasing water runoff.

Earthworms breathe through their skin and prefer a moist environment (at least 40 percent moisture). When it rains, many earthworms come to the surface and may be a nuisance. Since worms thrive in moist soils, their highest times of activity are in the spring and fall. During the winter, they migrate deeper into the soil. In areas where the ground freezes, worms can actually live through being frozen solid. 

A single worm possesses both male and female reproductive parts. Mating takes place around the soil surface when conditions are right — adequate moisture is important. A typical nightcrawler becomes reproductively mature in about one year and can live up to six!

Worms are crucial to the success of your compost bin. You can even have small worm bins to compost vegetable table scraps. Red wigglers should be used in a compost bin, rather than nightcrawlers. Nightcrawlers have too slow a reproductive cycle compared to red wigglers. 

Many pesticides that are applied to lawns can be detrimental to worms and should be avoided. Also, some fertilizers may repel worms or force them to move elsewhere.

On occasion, worms can become a nuisance in the lawn. If there is a high population of worms (which is quite rare), castings can build up on top of the turf. The only solution for this problem is to use a power rake to break up the clusters of soil. Count yourself blessed with an abundance of worms! 

So you like to drown some worms? Not only do worms help catch big fish (or big fish stories!), but they also are extremely beneficial for our soil. For more information on worms or vermicompost, refer to AG-473-18: Worms Can Recycle Your Garbage and ENT/ort-125: Worms as Pests in Home Lawns or contact our Center at (919) 775-5624.

Want more pertinent horticulture information delivered directly to your home computer? Subscribe to the Lee County home horticulture e-mail list. Simply send an e-mail to mj2@lists.ncsu.edu with subscribe leehomehort in the body of the message. You will then be a member of leehomehort@lists.ncsu.edu.

North Carolina Cooperative Extension in Lee County.