Earthworm Burrows

Gerb in Iowa posted excellent pictures of the earthworm burrows he found in his Moody Silty Clay Loam while putting in a new water line.  That immediately reminded me of Odette Menard's great talks about her earthworm studies in Quebec at the NNTC in January.

The 'lowly' Earthworm...I don't think so...

EARTHWORMS - The Benefits Improve the physical structure of the soil - improve water filtration rates and absorption rates helping the soil to drain better. Less runoff equals less watering and less erosion. - the tunneling activity improves soil aeration, porosity, and permeability. - increase moisture absorption and moisture available to plants. Castings absorb water faster than soil, castings hold more water than equivalent amounts of soil. Bhawalker Earthworm Research Institute - castings have the ability to absorb moisture from the air and hold it in a manner that plants can use. Bhawalker Earthworm Research Institute - 25 earthworms per square foot of soil equal 1 million earthworms per acre. Studies in England have shown that in healthy soil forty tons of castings per acre pass through earthworms bodies daily. A new USA study indicates 1½ million worms per acre which move 20 tons of earth each year. - studies have shown that with good food sources and favorable conditions, a field might have over 100 nightcrawlers per square yard. National Soil Tilth Lab - One earthworm can digest 36 tons of soil in one year. US Soil Conservation Office - the tunneling activity of worms helps breakup hardpan and other compacted soils. - studies have shown that 30% of a fields respiration during cold wet winter-spring months are due to earthworms. - A study in European orchards found that earthworms could increase the pore space in soil by 75-100% and that earthworm burrows accounted for _ of a soils air-filled pores. Earthworm Ecology and Biogeography in North America, 1995. What do you do to increase earthworm populations on your land? Ed Winkle