I tried using this for my P aegyptiaca and was going to use it for my other substrate requiring roaches, but it appears to irritate them. *they were trying to climb up the sides of the enclosure* Is it okay to use as a substrate, and were my observations simply their reaction to a different smell?

(Isn't cypress bedding supposed to have some insecticidal properties, at least according to the package?) If they look irritated they probably are. Try potting soil mixed with ground old leaves.

CYPRESS mulch is the one and only mulch that is SAFE to use as bedding for any creature. Pine and similar trees have naturally occurring insect repellants that irritate roaches, reptiles, etc. to varying degrees. Mulch sold as 'hardwood mulch' is usually not exclusively hardwood and often contains cedar which is very toxic to roaches. Cypress is totally safe and I use it in most of my roach bins mixed with oak leaves and coco fiber.

That being said, I do not use it in polyphagid enclosures. It is too much texture that they cannot seem to deal with. They seem to prefer smaller bits that they can be fully immersed in. Example is P. aegyptica. They prefer a substrate that they can actually burrow in, and cypress is not it. My polyphagids are in tanks that have a mix of: Eco-earth (coco fiber bedding), a couple handfuls of organic potting soil, dead leaves crunched up and mixed in, about 2" or more deep. In one half of the substrate I mix in a handfull or two of calcium sand so they have a sandy side and not sandy side of the enclosure. The adults live mostly in the leafy side, but the nymphs are mostly in the sandy side, and the females always leave the ootheca in the sandy side of the enclosure. I have had multiple generations of P.aegyptica and Ergaula capucina in this type of setup and the only thing I do other than feed them is mist regularly and add more dead leaves (which they slowly consume).

I have also heard that you can use nothing but vermiculite with some dead leaves thrown on top, but I have not tried that myself.

I don't think that Apsen has any volitile phenols or other kind of anti-insect chemical compunds does it. I used to use it all the time. I had heard that Cypress isn't very ecofriendly because they munch up whole trees to make the shaving instead of just using byproducts from lumber production (not that I'm an enviromental radical or anything like that, don't get me wrong). Does anybody know for sure if it's true?

You are correct... Aspen is a bug friendly product, though I found it to mold easily in my habitats. Cypress.... I suspect they do shred a whole tree, but am not too sure. Is there anything made from cypress lumber?

I'm going to try and use a mix of 25% aspen, 25% cypress, 50% shredded oak leaves. This sound good?

I'm glad you asked about that. I always thought cypress had insecticide qualities and always avoided any substrate that said it had cypress in it. I usually make my own substrate out of peat moss, oak leaves and sometimes vermiculite to keep in moisture. Some of the reptile substrates with cypress in them looked kind of appealing though. Like the forest bed type of stuff that's a mixture of cypress and dirt.