Unlike green plants, fungi lack chlorophyll, which means they can’t manufacture their own food and must derive nutrients from other sources. Some fungi can get nutrients by partnering with algae—or sometimes bacteria formerly known as blue–green algae. We spotted several colorful examples of lichens, the resulting organism, growing on stones and tree limbs. It’s a convenient arrangement: the algae live among the fungal mycelium and gather nutrients for their fungal partners, which in turn provide shelter for the algae. Although lichens grow on trees, they’re not parasitic. Several animals eat them, including wild turkeys, squirrels, and deer—and various birds use lichens for nesting material. In California, we have more than 1,900 species and the lace lichen is our State Lichen.
Most fungi are beneficial decomposers, breaking down organic matter such as animal droppings and dead trees. Some are parasitic on plants. Several of the mushrooms we saw, such as shelf fungi, were sprouting out of living trees. This meant that inside the tree, the fungal mycelium had taken hold.
Fungi range from microscopic in size to enormous. The so-called humongous fungus, a single organism in Oregon, has thrived for at least 2,400 years and covers over 3 square miles.
As we got started, Ryan cautioned us that mushroom hunters err on the side of caution: eating toxic mushrooms can result in liver damage and death. Ryan added that “every mushroom is edible, but sometimes they’re only edible once.” Toxic species often resemble edible ones. Experienced mushroom hunters use a variety of diagnostic characters to verify specimens they plan to eat. Unless they know for certain that a species is edible they stay away from mushrooms that have parasol-shaped caps and are small and brown. They also carefully examine the spore color—white spores often mean danger.
Mushrooms can accumulate heavy metals such as lead and cadmium, which is why it’s best to harvest edible mushrooms away from roadsides and railroad tracks.
The group saw brown deer mushrooms, Pluteus cervinus, growing on tree roots near the river. Ink cap mushrooms in the genus Coprinopsis were widespread on the river bank. These mushrooms are edible, but if eaten with alcohol, will cause severe vomiting. We also saw some colorful sulphur shelf mushrooms, also known as chicken of the woods or Laetiporus. These are edible and taste like chicken, although not everyone can eat them with impunity.
Unlike previous years, we didn’t see turkey tails (a shelf fungus) or oyster mushrooms, which are usually plentiful on cottonwood trees.
Ryan recommended a few resources that will help novices get started, including a natural history and identification guide by David Arora, All that the rain promises and more: a hip pocket guide to Western mushrooms.