1. Education
Oligochaeta! Oh Really? - Earthworms Around the World
Guest Column by GeoT

Dateline: 06/13/00

I'll no doubt "open a can of worms" with this one - but here goes.

Earthworms, plain and simple earthworms, which are part of the class known as Oligochaeta. We have all seen these slimy little critters - but how important are they in the general scheme of things? Ask Charles Darwin (yes, that Charles Darwin). He was the first to describe the importance of earthworms to the world's ecology. Well, not in the polar or extreme desert regions - no earthworms there.

Species of earthworms number near 2,700, and an average farm field in a moderately moist climate may contain as many as 1 million per acre! These guys are said to move from 7 to 18 tons of soil per year, bringing soil from the lower layers to the surface to be deposited as "casts." Those little mounds of soil coils. In the process of doing this they automatically provide a mechanism for aeration and water penetration into the soil layers. No wonder garden catalogs sell boxes of earthworms!

Earthworms measure from 1 inch to as much as 11 -12 feet. Most are a reddish color - but one nonconformist worm in the Philippines is blue, and another in the United Kingdom is green. They have little bristles on each of their segments, that, with the worm's wriggling allows them to "dig in" and scoot through the soil. Dissection reveals no less that 5 hearts! Earthworms are born from cocoons as miniature adults and immediate begin the process of ingesting soil for nutrition.

Now, what may be common in one part of the world, surely is not in others, i.e. worm composting. Ever hear of such a thing? I hadn't, until Karen, from Australia on Geography Chat told us about it. Worm composting is a way to reprocess kitchen waste into valuable fertilizer for the garden. And side benefits would be saving landfill space and elimination of the need to store the decaying vegetation for several days at a time. The worms merrily chomp away and turn those lettuce leaves into great compost for the marigolds.

Now, speaking of Australia - if we are looking for the earthworm giants in this world of ours - here is a place to find them! In Victoria, the southeastern of the mainland Australian states - the part known as Gippsland. Here, are among the largest earthworms in the world. They live along stream banks, preferring the blue/gray or reddish clay soils and grow to as much as 12 feet and weigh in at 1.5 pounds! Careful with them though, they bruise easily and may perish as the result of handling. In fact, they are protected by law.

It would be inaccurate to think the people of Gippsland aren't proud of their giant worms. Each March there is a festival celebrating the worms. The Karmai Festival at Korumburra. No, the worms are not part of the buffet - the Maori of New Zealand do that.

But, move over Australia and Gippsland - the largest earthworm ever found was in South Africa and measured 22 feet from "nose to tail." Now I wonder if the Norwegians have a fish hook big enough for that guy!!??

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