Ecology and management of the commercially harvested American matsutake.

Cover-En route to retail markets, young mushrooms retain their freshness better than older ones.Before the veil between the cap and the stem breaks, they are considered "buttons," and if there is no other physical or insect damage, they are graded as "number 1's," and command the highest price at buying stations.The large, young American matsutake shown in the photograph are just beginning to lose value.The veils on these specimens are starting to separate from the cap and they might be demoted to grade 2, depending on market conditions and the discretion of the buyer.In areas that experience intensive harvesting, the financial incentive to collect immature mushrooms is the basis for concern about diminished reproductive success due to decreased spore dispersal.To address this concern, mushroom harvesters often intentionally disperse the spores of commercially defective mushrooms, land managers limit collection to certain times or areas, and scientists are studying the reproductive biology of the Tricholoma magnivelare.The inset drawing shows mushroom development and relative position to mycorrhizae in a soil profile (Hosford and Ohara 1990).