Hi geincvp,
More than likely you are harvesting Canadian nightcrawlers from your yard. Are they really big? Or are you getting them from a composting pile? The Canadian nightcrawlers are not composting worms and will not breed in a captive environment. The best worms for composting are the red wigglers (Eisenia fetida or foetida), the European nightcrawlers (Eisenia hortensis), and the African nightcrawlers (Eudrilus eugeniae). If you like to fish too, I recommend either the European nightcrawler or the African nightcrawler because they are bigger than the red wigglers.

When you say harvested from your yard are you harvesting them out of a compost pile? Earth worms can be classed in two general types, those that live in the soil and those that live in the decomposing surface material.

Soil dwelling worms are not suitable for raising in a worm bin. They will tend to come to the surface to feed on decomposing matter but borrow back down into the soil. They will also deposit(poop) underground which is good for soil health but makes the compost inaccessible for the vermicomposter.

The types mentioned by beth are types that are well suited to keeping in a worm bin, they live and reproduce in piles of decomposing matter.

Don't think that a hybrid can exist. The Canadain Nightcralwer (I believe) belongs to the genus Lumbricus whereas Red Wigglers belong to the genus Eisenia. If I'm not mistaken, plants and animals of different genera cannot interbreed. I've also read that annelids (worms) will not be able to breed between species.

Can you build a micro compost heap in a shady corner of your property with a quart, half gallon or gallon of kitchen scraps? After a week or two peek under the tiny pile for a ball of worms. These should be compost worms. Almost every area has their own type best suited to the local area.

Your worm population will grow as you knowledge about vermicomposting grows.

It will be a good day when you see worm eggs, and even better when you see baby worms, and way better when those worms grow and become adult.

Unless tons of food are waiting to be processed, one can say, "I'm not going to pay a lot for these worms."

I am presently growing my colony but I keep giving half away so others can vermicompost too. So the growing is slow.

I'd go with beth monsterworms and guess that you are harvesting earthworms from the soil which are endogeic (soil burrowing) and not the the epigeic (surface or compost dwellers - such as the red wigglers (Eisenia fetida). The worms definitely don't hybridise.

Here is a link that might be useful: Earthworm versus Redworm

You can check with friends and neighbours, who has composters (NOT tumblers) or compost piles. There might be worms in there. Even better if you can find an aged manure pile. There will definitely be compost worms in them. Apparently as the weather starts to get colder, the worms will form a ball and therefore easier to collect.

You are NOT wasting your time with the "right" native worms.

Thanks for all the responses. Yes I am getting the worms from my soil, under rocks and in piles of mulched grass clippings, but I get the same worms out of my compost bin. I dont think they are canadian nc's because the largest is only about 4 inches in length. I have transfered them to newspaper bedding bins but my take from the responses is that these will not breed or produce castings. Am I correct?

The worms from the compost bin will breed and produce castings. They did that in the compost bin, didn't they.
How well they do it compared to the species, that I don't know.
You might want to get some of the mulched grass clippings and leaves too for bedding rather than just newspaper so the environment change won't be too drastic. Less shock. Worms can get stressed too you know, LOL.

... and valium is so hard to administer to worms ... such little pills.

What fun. Most Canadian Crawlers are twice as long as what you are reporting. Try some of the leaves/compost as starter bedding.You might want to check out "The Complete Compost Gardening Guide" by Barbra Pleasant;Deborah L. Martin. They use "Yard" worms for vermicomposting and offer pictures and opinions.I don't think you are wasting your time at all.

Curt :-)

rom: maybe crush them little pills? That should work, lol.