Collection location: Howarth Park, Santa Rosa, Sonoma Co., California, USA [Click for map]
The pileus seems slightly bearded. Latex turned pale yellow instantly. Forgot to taste, stalk seems slightly scrobiculate. Photographs totally crummy. Pileus 6.7 cm, stipe 1.3cm wide at apex. Fruiting with manzanita, bay, oak.
Looks more like L. alnicola, which can also be scrobiculate. The real difference between the two is that L. scrobiculatus has yellow staining latex, but also that the latex will stain the gills yellow-orange, so the gills tend to dev. yellow stains as it ages. The gills here look too clean and white. The one caveat is that as L. alnicola get really old and the gills start to dry out, they turn yellow, so when they are really old they are hard to tell apart.
But anyway, this looks more like L. alnicola.