The first and most important rule for mushroom foragers is: "When in doubt, throw it out."
Do not gather mushrooms that you can't absolutely, positively identify. Leave all unknown or questioned mushrooms alone, even if it means walking past many mushrooms of every color and shape before finding one you recognize.
Mushroom 101: The best way to learn about mushrooms is to have someone show you the edible species; spending time studying field guides also helps. The perfect field guide for Alaska doesn't exist.
The books I like best are David Arora's "Mushrooms Demystified" and "All That the Rain Promises and More: A Hip Pocket Guide to Western Mushrooms". I also like "The New Savory Wild Mushroom" by Margaret McKenny and Daniel E. Stuntz. "Alaska's Mushrooms: A Practical Guide" by Harriette Parker is good, but very limited in scope.
I made a decision a long time ago to stay away from most gilled mushrooms. The differences between edible gilled mushrooms and those that are poisonous can be very subtle. Mushrooms without gills -- morels, puffballs, hedgehogs and boletes -- are much easier to identify than gilled mushrooms, and far less likely to be confused with dangerous lookalikes.
Younger is better: Search for young, firm mushrooms. Their flesh is dense and delicious. More importantly, insects, worms and other competitors are less likely to have reached them.
Look around: Look very carefully before picking the biggest and most impressive mushrooms to catch your eye. The longer a mushroom is above ground, the more likely it is to be so infested with worms and insects that it's unsuitable for human food. Be sure, however, to look around the area where you find rotten or infested big mushrooms as you will often spot younger, less developed fruit of the same variety emerging.
Dig in: Gather the entire mushroom, base and all, using your fingers to dig down around the stem and gently free it from the underground mycelium. Especially when gathering boletes, do not cut the stem with a knife. If you cut the stem, leaving part of it in the ground, the thick fleshy stump can rot and kill the mycelium. (Think of mushrooms as apples and the mycelium as the tree; if you kill the mycelium/tree, you won't get any more mushrooms/fruit in future years.) Fill in the hole left by removing the mushroom with dirt, moss, or leaf mold.
Clean dirt pronto: Immediately after harvesting a mushroom and before you put it in the basket, use the knife to trim the dirty stem end and any damaged areas. Don't put mushrooms with loose clumps of dirt in your basket. If you do, dirt from the upper layer of mushrooms gets all over the lower layers, making them harder to clean when you get home. Likewise, if you see worms or other insects in the mushrooms, cut them out immediately; the longer they're in the mushrooms, the more of your dinner they'll eat.
Avoid temptation to wash: Wild mushrooms should never be washed in water. Use a soft brush to remove as much dirt as you can from the caps and a damp paper towel to wipe the cap clean.
Inspect it: Cut mushrooms in half and inspect for worms or other insects; remove as necessary. Don't worry about a few worm holes; it's the worms themselves you want to eliminate. If the pores beneath the cap are soft or soggy, remove them.
Paper, not plastic: Store fresh mushrooms in paper bags, never in plastic.
How to Dry Wild Mushrooms
In Anchorage, the best way to dry wild mushrooms is in a dehydrator (in other climates, you may be able to air dry them). Clean the mushrooms well and slice them 1/4" thick. If you slice them thinner, the slices stick to dehydrator trays and are impossible to turn.
Put the mushroom slices on trays in a single layer. Start running the dehydrator, and turn the slices every couple hours until they're dry. This helps the mushrooms dry evenly and also prevents them from sticking to trays. Rotate the trays each time you turn the mushroom slices.
When the slices are completely dry, let them cool and pack in glass jars with airtight lids. If even a few slices are still damp they can cause an entire jar of dried mushrooms to spoil, so be certain the mushrooms are dry.
It takes at least six months for dried boletes to develop their full flavor. The longer you store them, the better they taste.
Laurie Helen Constantino is a cook and writer who runs the website Laurie Constantino: Recipes and Resources for Food Lovers This article is excerpted from one that first appeared on her site and is published here with permission.