ANGWIN — The 3,500 acres of Las Posadas State Forest are far off the normal routes of wine lovers and other tourists — except those searching for tasty morsels near the damp, leaf-littered ground.
The sun had barely started rising over a filmy fog Sunday before more than 30 visitors streamed into this woodland preserve outside Angwin. Leading the hikers were two mushroom enthusiasts, guides who would share their secrets for finding the hideouts of chanterelles, matsutakes, maple syrup-scented candy caps and other fungi to carry from forest to plate.
“It’s like treasure hunting for me,” said David Tsujimoto, one of the hikers, who took up mushroom foraging in Washington state before moving to Elk Grove last year. “Hiking is fun, but I prefer to be out there on the trail with something to look for.”
The Wild Mushroom Forage highlighted the third day of the Napa Truffle Festival — an annual four-day gathering organized by the American Truffle Co. — whose fifth edition began Friday. While the festival’s slate includes various dining and wine pairing courses, cooking demonstrations and seminars, the program also offers guests a chance to tour the lands from which the delicacies spring.
David Campbell, a writer and teacher on wild mushrooms who leads fungi-hunting tours in the Bay Area, had chosen the placid Las Posadas woods largely for its unusual blend of firs, madrones, live oaks and other trees on the same ground — a variety of hosts, he hoped, for a diverse array of mushrooms for hikers to uncover.
Ten percent of mushroom species are edible, and the vast majority are nonlethal though unpalatable, but Campbell cautioned his tour group to respect the toxicity — eye-pleasing though the mushrooms might be — of the remaining 5 percent.
“You can’t say to yourself ‘Oh, it’s so ugly, it has to be poisonous,’ or ‘It’s so pretty, it has to be good to eat,’” he told his audience before their two-hour forest excursion. “There’s no room for intuition. There’s some very ugly mushrooms that are very delicious. And there’s some very pretty mushrooms that’ll kill you dead.”
The pickings seemed slim at first for the group. Or rather, as Stephanie Jarvis pointed out to the group, others already had picked the grounds close to the path, where bits of caps and stipes (mushroom stems) could be seen, discarded and ignored.
“Most people come in and clean out everything they find on the path,” said Jarvis, a mycologist who owns Napa Valley Fungi and cultivates mushrooms for culinary and medicinal uses. “So to find something, you need to go off the path.”
In twos and threes the hikers spread out on the sloping wood, following their guides’ advice to seek the markers of fungus-friendly habitat — a certain kind of fir here, a fallen madrone there, even a spot where the nighttime fog had condensed into a constant drip from the branches down to a moistened patch of soil.
With pocketknives and hand spades, the foraging party filled their small bags with frill-lipped black chanterelles, meaty portobello and brown-topped porcini. At last the foragers returned to their starting point, where a fallen tree trunk became a table for their array of red, yellow and white quarry.
The haul of fungi was not especially large — moisture from the December rains was slowly evaporating and leaving the soils less hospitable — but Jarvis, the mushroom guide, was happy to share her enthusiasm with others who might themselves return to the woods for their own hunts.
“It’s all about the search,” said Jarvis. “It’s like Easter egg hunting, only for grown-ups.”