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WSU/Pend Oreille Extension introduced the Sense of Place series in 1999, with a focus on local landscape and natural history of Pend Oreille County, Washington. A partnership with the Kalispel Tribe of Indians Natural Resources Department has allowed us to expand this program through EPA funding to include more classes, a newsletter and this website.

The Higher Fungi

by Drew Parker

It is common knowledge that mushrooms are more abundant following rainy periods and conversely are seldom seen during a drought. It follows that by looking at the general distribution of moisture over a year in the Pacific Northwest we will deduce that the best times for mushrooming will begin in the spring, taper off as conditions dry out over the summer, and resurge in the fall when cooling temperatures bring about fall rains. Afact that mushroom seekers sometimes fail to appreciate is the influence elevation has on the timing of mushroom fruiting by its distortion of those annual patterns.

Temperatures are around three degrees cooler for every thousand-foot rise in elevation, and though droughts do occur at all elevations, cooler temperatures higher up tend to promote moister conditions in several ways. These include slowing the melting of the snow pack, generating precipitation as brief showers, fogs, and dews, and slowing evaporation of all residual water, resulting in conditions that favor the fruiting of mushrooms. Within the ecological range of each species, the appearance of mushrooms, like the ripening of huckleberries, occurs sequentially beginning at lower elevations and moving up slope as the season progresses. The Morels, which are spring species, are a good example of this phenomenon and can be found from valley bottoms to sub-alpine areas over the season. In our region there is even a diverse group of macrofungi known as “snowbank mushrooms” that of course fruit in proximity to snowbanks drawing on their meltwater as they retreat up the moun- tainsides from spring into summer. This phenomenon is apparently unique to western North America where most of the species in this group are endemic.

By heading for the high country when the forests dry out in the lowlands we frequently find a variety of fungi taking advantage of the cooler, moister conditions there. While on the trail, besides Morels I have found other edibles such as the King Bolete (Boletus edulis), the White Chanterelle (Cantharellus subalbidus), the Gypsy Mushroom (Cortinarius caperatus) and the imperial Catathelasma imperialis. I’ve also seen the beautiful but toxic Fly Agaric (Amanita muscaria), and a wide variety of other lesser known but equally interesting species, all found in the high forests and some right up to where the trees surrender to the scree slopes and slab rock.

When we approach this upper limit of the conifers we find harsh exposed habitats with thin soils, great temperature swings, and once the snows are gone, little water. To survive on these extreme sites trees and fungi utilize an age-old symbiotic relationship called mycorrhiza that enables both to live where neither could otherwise. Simply put, the trees barter carbohydrates in return for essential elements and water during dry periods. Some fungi are so adept at collecting water in relatively dry places that they can afford to exchange it with trees for needed nutrients. High elevation trees such as whitebark pine (Pinus albicaulis), engelmann spruce (Picea engelmannii), and subalpine fir (Abies lasiocarpa) all form mycorrhiza with many different fungi. Indeed they are positively promiscuous in these relationships. In limited studies whitebark pines have been found to associate with over fifty different fungi and undoubtedly there are more. Such is life on the biological “edge”. So don’t set your mushroom field guides aside so fast when the summer heat arrives. Grab your pack and follow the mushrooms up the slopes and on to the subalpine forests and beyond. By doing so you may be rewarded by finding not only some more familiar lowland species, but also a range of others endemic to the higher forests.

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