Base of black cottonwood. A bit soggy.
Found by truffle pups in a stand of 15 year old Douglas fir that was thinned 5 months earlier. sparse ferns present, 50 feet away from a boggy area (and only a foot or two higher in elevation than the bog). Lots of water present at the site.
Found by truffle dog in an orchard of Douglas fir. Fruity truffle scent.