Most whole grains work well as spawn; wild bird seed, if you remove the sunflower seeds, is an excellent, cheap spawn. Furthermore, horse manure, coco coir, and straw all work well as bulk substrates. Of course, there are other things that work well or that can be added.
And would these be used without the vermiculite? Do you mix them with anything? Also, I assume that some of these, like bird seed or straw, have to be ground up pretty fine, right?
They are not mixed with the verm, they are used by themselves. Also the seed or straw is not ground up, they are used whole. Check out fungifun.com for lots of good info.
Yeah, just use them straight. There are instances where vermiculite can be added to control moisture, but it's not always necessary.
brown rice flour and vermiculite is fairly cheap, why don't you want to use it? Also it seams to be a favoret among growers.
There's no problem with the vermiculite, but the brown rice flour is scarce. In my experience, it's a pain looking around for it. If I have other options, it makes my shopping experience so much easier.
Brown rice flour is used mostly by people who are just starting out. Grains are easier to use as spawn and easier to create in larger quantities. It's impractical to inoculate containers holding more than one pint of BRF at a time because they will tend to stall during colonization at some point. However, it is much easier to colonize large containers of whole grains since they can be shaken around in order to spread the mycellium, effectually hastening colonization. Grains are easily colonized in quart jars, which are eight times as voluminous as half pint jars standardly used with BRF. It is definitely more efficient and frugal to use grains; one six-pack of quart jars is nearly equivalent (though not quite because you shouldn't fill grains to the brim of the jar) to four twelve-packs of half pint jars.
