The difference between fresh cut live logs and standing dead wood is one of inoculation. You can be pretty sure the former is sterile and uninfected, and you have no idea what kind of spores have blown in and taken up residence on the latter. If you drill holes and pound your dowels into something that is already infected, you may be setting up the battle of the hyphae between different competing
fungi. Who knows if the type you want to grow will win that competition.
Definitely don't bury them, that just brings soil fungi into the picture and makes it a multi-way competition.
Shade is good, completely out of the sun is even better. If it sees any daylight, then algal spores may start to colonize the log as well, and instead of a pure fungal culture, your log could have a mixed algae/fungi combination growing -- a lichen.
How ever you store them while the fungi are growing, remember that fungi need air and
water --
enough air flow to get needed oxygen, but not so much that it dries out.
I'll let someone else take a crack at which wood goes best with which mushroom.
