My own experience is that vermiworms in an outdoor pile help a lot. "Seeding" your pile can't hurt, and probably will help - just that in my case the compost worms turned up on their own. Compost worms will generally do fine even in a hot pile, _as long as_ they have somewhere with moderate temps to retreat to (like a layer of stuff at the bottom), and especially if they have access to ground. (No idea whether your cement-hard clay would be soft enough for them). Mine also survive long, cold winters and bounce back every spring. Obviously the pile has to be otherwise acceptable to them, food and moisture wise, but this usually takes care of itself for mixed piles.

The only caveat I have about this is that 'local' compost worms are more likely to survive local conditions, because they've already been doing so.

So my suggestion: wait until the hottest phase of your current pile is done, then add some. Wait a while, maybe add a few more from time to time, and see what happens. If conditions are good, they'll do fine and you'll have many more in sufficient time.

Is the compost pile likely to soften the surface of the clay over the months, or are the held moisture, decomposing OM, and burrowing vermin going to need a lot of help from a shovel?

This is, fortunately (for me), outside my area of experience. From what I've read (here and elsewhere), compost and the things that go with them (bugs, earthworms, etc) will soften eventually, but some like to help it along with some bit of help from shovel. I kind of get the impression that it's as much adding lots of organic matter that helps - meaning I can't tell whether it's the extra layers or real softening going on - but probably both.

Note you said 'vermin' - I wouldn't expect vermicompost worms to do much in this area on their own, they're not really burrowers, and mostly live in soft stuff or shallow. They won't hurt, though.

I did have a yard with fairly poor soil underneath, including some clay - the previous owner had brought in tons and tons of topsoil ('black earth' - great stuff). Made for great soil. But climate totally different than yours, so I won't claim that experience is transferable.

Keep in mind the environment earthworms need to exist, a moist, cool, environment with lots of organic matter to feed on. A newly constructed compost pile is not going to be a cool, moist environment if constructed properly although it may be moist it should be much warmer, around 100 degrees F, then earthworms can exist in. True also of Pill Bugs, Sow Bugs, slugs, snails, etc., that need a cool, moist environment to live in.

There are aerobic bacteria, Psychrophiles, that work at low, about 32 to 77 degrees
F, temperatures and there are Mesophiles that work at temperatures about 60 to 115 degrees F and then the Thermophiles that work about 120 to 150 degrees F. These are the primary digesters of organic matter in compost piles. Temperatures above 55 degrees F can be fatal to earthworms. a compost pile that is too wet (wet enough for earthworms) will not have enough air to support the bacteria that should be digesting the material.

A lack of soil life indicates a lack of adequate amounts of organic matter in the soil. To learn more about the soil you have and what you need to do to make that soil into the good healthy soil needed to grow strong and healthy plants start with a good reliable soil test for soil pH and major nutrient levels.

http://aesl.ces.uga.edu/soiltest123/Georgia.htm

Then these sample soil test may be of some help as well.

1) Soil test for organic
material. From that soil sample put enough of the rest to make a 4 inch level in
a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and
replace the lid, tightly. Shake the jar vigorously and then let it stand for 24
hours. Your soil will settle out according to soil particle size and weight.
For example, a good loam will have about 1-3/4 inch (about 45%) of sand on the
bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above
that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole
1 foot square and 1 foot deep and fill that with water. After that water drains
away refill the hole with more water and time how long it takes that to drain
away. Anything less than 2 hours and your soil drains’ too quickly and needs
more organic matter to slow that drainage down. Anything over 6 hours and the
soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful
of your slightly damp soil and squeeze it tightly. When the pressure is
released the soil should hold together in that clump, but when poked with a
finger that clump should fall apart.

4) Smell. What does your
soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant
odor? The more organic matter in your soil the more active the soil bacteria
will be and the nicer your soil will smell, to a point. Too much organic matter
can be bad as well.

5) Life. How many
earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5,
according to the Natural Resources Conservation Service, indicates a soil that
is not healthy.

kimmq is kimmsr

Can't do the professional soil test in the near future, we're very broke (one of the reasons we're interested in turning our organic trash into useful products like food plants). As for the other tests...

1) Don't have a suitable jar and can't currently get one, seriously that broke.
2) There is still water standing in the unused plot that I put there last night to help the paper and cardboard stay put. The coating is wet and soggy, it's not resisting the water, but when the water hits the clay it just stops.
3) This soil doesn't have a "slightly damp" mode. When it's dry, it's like concrete, except it cracks and shatters a little bit easier. When it's wet, it's very sticky.
4) The clay soil has no smell at all.
5) 0 worms found digging up a 5 foot by 7 foot bed down to a 1 foot depth.

Only the presence of weeds before we started gives me any indication that this clay can support life at all. Once I get them dried out and shredded down (I scythed them out, they're a bit too long right now and will mat if laid back down like that) I'll be adding them back to the heap I'm building.

I still haven't seen any earthworms in or around the compost heap in the raised bed, but there has been an explosion of pillbugs and sow bugs, some millipedes, the odd centipede or grass spider, and a few earwigs in there. I found some earthworm predator planarians in the ground nearby, which suggests to me that there ARE earthworms around, but they're having a tough time not becoming lunch... I'm killing the planarians whenever they're found, now.

I temporarily peeled back the layers of unfinished compost I have in there for examination, and the middle of the pile is a bit wetter than I'd like, but it doesn't stink. It is losing texture and turning black, which creates an interesting visual contrast with a white powdery-looking fungus which is ubiquitous.

The moisture the OM is holding against the clay is helping a lot. Pulling up the edge of the base cardboard layer, I could dig into the clay and scoop out a handful with just my fingers; it clumps when squeezed with minimal stickiness, and can be broken again with a firm prod. The only way I could tell this was the original clay was the mass of weed roots still in it.

My vermicomposting redworms are breeding, but not too quickly; they haven't yet reached critical mass for a continuous orgy. I think I'll save them for now, and seed the plot preparation heap with them in a couple of months, after they've had more chance to multiply, the heap has more time to break down, and I've killed off more of the nearby planarians. Any native worms that find their way in, good luck to them in the meantime.

Oh, and oddly enough, the pillbugs and sow bugs in there seem to like the heat. The most lively area in the heap is the part that's hot enough to be uncomfortable to touch, far above body temperature. Not sure what to make of that, but I'm not complaining.

That all sounds good. I wouldn't worry about the bugs, fungus or earthworm predators - all are good signs. As noted before, there's really no need to seed your pile with compost worms if you need them elsewhere. Glad to hear that it is helping the hard clay to soften up.

The worms used for vermicomposting, Red Wigglers, "Eisenia fetida", and redworms, "(Lumbricus rubellus", need an environment with a very high level of organic matter and they do not live in soil very well.

The earthworms that will eventually inhabit your planting beds will move in when conditions are right for them. It takes time, especially if the soil was not a good rich soil before.

Perhaps this article might be of some help.

http://www.gardeningknowhow.com/composting/vermicomposting/worms-for-vermicomposting.htm

kimmq is kimmsr

I read something recently about an informal experiment in which red wigglers were added to a lasagna garden bed, and the bed far outperformed the control beds (and the worm population exploded). Does this sound like a fluke? I'm not exactly doing lasagna gardening here, but there are some similarities, and I wonder if there's something here I'm not taking advantage of, and should be.

Please cite that article. While a Lasagna bed is composed of mostly vegetative waste it still should not be wet enough to support a worm population because that level of moisture most likely would exclude the air plant roots need to uptake nutrients as well as moisture.

kimmq is kimmsr

I think redwormcomposting dot Com did an experiment like that. I kinda did also. I got tired of screwing around with worms, and dumped them into a 5x10 x 2 feet deep bed I dug. Did the whole filling it with cardboard, leaves, horse manure and whatever else I could find before adding the worms over a 2x5 foot section on one end. These were EF and european nightcrawlers. They have taken over the whole bed, as are a variety of squash and melon that grew from the worm bins. I don't know how to precisely quantify "better" than anything else, but there are a lot more worms than I had before and a lot of crops in that same bed.

Here is what I was talking about. http://www.redwormcomposting.com/gardening/lasagna-gardening-with-red-worms/

So was the better growth the result of adding the worms, the weather, better materials in the mix, or one or more other variables?

kimmq is kimmsr

I already said I can't quantify "better"-only that it did actually work well. However, I am fairly certain the weather didn't vary much in the 100 feet between this worm bed and the rest of my garden.

My lasagna bed has been colonized by native wild worms, with zero added from other sources. My vegetables are growing terrifically as well. I have not experienced any of the moisture/air issues that were questioned previously.

This is my 12'x4'x8" bed's second year and it has composted down from 15" deep of raw material to level with its 8" frame. First layer of cardboard directly on bare earth.