Earthworms

Earthworms apparently are rare enough in sub-arctic Alaska and Yukon that a face-to-face meeting with one is uncommon. Perhaps the earthworms' cousins, the almost-legendary iceworms, are more numerous in the North.

Earthworms live in strange places. They survive in sewage beds, manure piles, beneath the bark of trees, and in tropical ferns growing high above the ground. Able to live submerged in water, earthworms have been found in mud beneath deep lakes, and also in moss on rocks above the beeline in the Himalayas and the Andes.

Despite this versatility, earthworms require acidic to neutral soil (pH between 4.5 and 8.4). This requirement, more than anything else, seems to prevent earthworms from living in northern soils, where the forest soil typically is too acidic.

Many years ago, a student dug up earthworms from soil adjacent to a dormatory on the University of Alaska at Fairbanks. During the summer of 1980, U.S. Geological Survey geologist Florence Weber found an earthworm in organic soil 20 inches below the surface in the valley of the upper Salcha River, near Fairbanks.

It may be that earthworms are like pigeons; they exist only at far north locations where people or some other organisms have created a suitable environment. If this be true, the existence of earthworms in soil may be a hint that the site where they are found is a current or previous human habitation.

In an attempt to pin this matter down better, I invite readers who have found earthworms in northern Alaska or Yukon to write or call me. Putting the information together, we might be able to create an informative map of the locations where earthqorms exist in this part of the world.