It's an ancient volcano so it's basalt. The south side in particular has been eroded by the Missoula floods and it's columnar basalt core, (similar to Beacon Rock) is exposed.
On that picture of the trees you write "Douglas Fir." Since it is not a true fir you need to write it this way: "Douglas-fir." Anytime you see it unhyphenated it is wrong.
Hi Brian - Thanks for the vote and compliment. Yes, I see now that you have a good description for Wind Mt. on your page. I should link back to yours - it's got more info!
Nice work yet again... never answered your que. before about when I was coming to Washinton b/c the time had already come and gone... I ended up playing in the Enchantment peaks area fro four days around ingalls Peak and Mt. Stuart. An incredible area.