Understory Vegetation and Ectomycorrhizal Sporocarp Diversity Response to Pine Regeneration Methods in Oaxaca, Mexico

Abstract

Abstract This study was carried out over a period of 3 yr in three stands of Pinus oaxacana in Oaxaca, Mexico. Our objective was to determine if pine regeneration, understory vegetation, and ectomycorrhizal (EM) sporocarps respond to increasing levels of site disturbance 5 yr after application of silvicultural treatments. Numbers of pine seedlings, trees, shrubs, and herbs, and numbers and richness of EM sporocarps were assessed in a control stand, a thinned stand, and a thinned and controlled burn stand. The thinned stand without slash burning (Seed Tree) had twice as many pine seedlings compared to the thinned and burned stand (Seed Tree with Burning). The number of shrubs was about twice as great in the treated stands compared to the control. The number of herbs in the control stand was twice that of the Seed Tree stand and four times that of the Seed Tree with Burning stand. Succulent plants were present in low numbers in the control stand and were not found in the treated stands. The structure of the EM community was evaluated by identifying the sporocarps and sclerotia. Abundance and richness of fungi did not differ among stands, but species composition was significantly different. Cenococcum geophilum, Laccaria laccata, Russula emetica and Lactarius crysorheus species were common in all three stands. Although L. laccata was present in the three stands, the number of sporocarps decreased with increased disturbance. Sporocarps of some EM species were found only in the control stand (e.g., Clavariadelphus truncatus, Craterellus fallax, Helvella crispa, Hydnum repandum) and others only in the treated stands (e.g., Amanita gemmata, Lactarius chrysorheus, L. volemus). West. J. Appl. For. 18(2):101–108.