Originally printed in the March 12, 2003 edition of the Illinois Valley News
With the recent warmer, dry weather, some plants are coming out of their winter dormant periods. Some people, like me, are beginning to think that it’s time to start digging in the dirt to start the new garden season. It seems that digging around in the dirt will make spring come sooner, at least it doesn’t slow it down any. This year it would probably be better for the soil if we had more rain and cooler temperatures to put more snow in the mountains.
Soil is an amazing substance. It’s made of tiny pieces of rocks called sediments. It also needs to have some water, minerals, and dead organic material. Good soil also contains a great variety of living organisms, most of which can not be seen without a microscope. Bacteria and fungi are very abundant and most useful in helping to decompose dead organisms into useable nutrients which plants can absorb. This process puts vital chemicals back into the living cycle once again. Also assisting with this decay process are nematodes, which are microscopic worms which also can be found as parasites in most living things.
Among the visible living organisms in the soil are grubs, or beetle larvae and earthworms. Earthworms are a reliable indicator of good soil because worms need the same ingredients that flowers, fruits, and vegetables require. Worms need moisture, but not too much or they can’t breathe. This is why sidewalks and asphalt become covered with worms after a heavy rain. They are coming to the surface to get more oxygen and many can’t find their way back to the soil again. They obtain oxygen directly through their skin, and oxygen dissolved in a little water will pass through the skin directly into their blood system. Carbon dioxide is released in the same manner.
Worms also need dirt that is not too compact or too sandy in order for them to move about freely. Worms are great cultivators which then allows plant roots to extend more easily through the loosened soil. Another requirement of worms is humus or dead organic matter. As with plants, this is their source of nutrients. As they eat their way through the soil, their digestive system extracts the needed chemicals and then the excreted material also fertilizes the soil for plants. Therefore worms and good gardens go together hand in No, they do not have hands or feet either but they do have little bristles that can be extended out through the body wall so that robins have to work for their lunch.
Lumbricus terrestrius is their scientific name, and it comes from “lumbricus” which is Latin for earthworm and “terra” which is Latin for earth or ground. Therefore the name means the earthworm that lives in the ground, a very sensible name I think. They have rather complex body systems and are usually studied in biology classrooms. The circulatory system is composed of arteries, veins, and capillaries, along with multiple tubes called hearts which circulate blood throughout the body. Earthworms are hermaphroditic, which means they have both male and female sex organs in the same individual. The white band, about one third of the body from the head, is called the clitellum and produces a mucous bag which hold the fertilized eggs until they are ready to open.
The lowly earthworm is very vital to maintaining good soil in a garden. They are also a vital source of food for robins, moles and other animals. Studies are being conducted to determine their value in breaking down toxic materials in soil pollution problems. Be kind to worms.