yes you can burn cactuse
Its wood isn't it
yes. just be sure it is seasoned (dried) properly. that goes for any wood.
While you can burn most woods, I would pass on the arborvitae. As an evergreen, you will get a LOT of creosote, fast burning, short lasting fires. It also contains a toxin believed to be a hallucinogen. A small amount used as kindling may not be a problem.
Burn cactus in a furnace.
no
Yes it can
Check with Martin for an owner's manual. Unless a fireplace is specifically rated as multi-fuel, a gas fireplace cannot safely burn wood.
No, it is not safe to burn. It is toxic.
You really should not burn ANY solid fuel in a gas fireplace.
Yes
I do.
Yes.