Basic Guidelines: In the strictest sense, nature photography should not include "hand of man elements". Please refrain from images with buildings or human made structures like roads, fences, walls. Pets are not permitted. Captive subjects in zoos, arboretums, or aquariums are permitted, but must be declared, and must focus on the subject, not the captivity. Images with obvious human made elements will likely be deleted from the thread, with an explanation to the photographer. Guidelines are based on PSA rules governing Nature photography which also cover the Nature Forum. Keep your image at/under 1000 pixels on the long axis for in-line viewing. Note that this includes photos hosted off-site at Flicker, Photobucket, your own site, etc. Each member please post no more than just one image to this weekly thread per week. Craters of the Moon National Monument in Idaho, USA, is a fascinating place. I've visited other volcanic sites, but this one is somewhat unique. One feature I've not seen anywhere else (though I'm certain they exist) are "tree casts". This subject is one of several examples, where the pattern of the tree bark is preserved in relief where the lava wrapped the tree. The holes penetrating into the solidified lava are the negative impressions of the tree's branches.