GARDNERVILLE, Nev. (AP) — A Northern California wildfire has crossed into Nevada, prompting new evacuation orders, but better weather is helping crews battling the nation’s largest blaze in southern Oregon. The Tamarack Fire, started by lightning south of Lake Tahoe, has now burned more than 68 square miles. Authorities say more than 1,200 firefighters are battling the blaze, which has destroyed at least 10 structures. Oregon’s Bootleg Fire has burned an area about half the size of Rhode Island but authorities say lower winds and temperatures are helping efforts to surround it. Also, the fire is approaching an area burned by a previous fire, which could slow its growth.