Survival and Growth of Pine Hybrid Seedlings With Pisolithus Ectomycorrhizae on Coal Spoils in Alabama and Tennessee

Abstract

AbstractContainer‐grown seedlings of specific pitch pine (Pinus rigida Mill.), loblolly pine (P. taeda L.), and pitch × loblolly pine (Pinus rigitaeda) hybrids were grown for 2½ years on unamended coal spoils in Alabama and Tennessee with Pisolithus tinctorius (Pt) ectomycorrhizae and, in separate plots, with naturally occurring ectomycorrhizae. The hybrid lines grew as well as or better than the loblolly or pitch lines. Seedlings with Pt ectomycorrhizae grew faster than seedlings with naturally occurring ectomycorrhizae. There was a significant genotype × mycorrhizal interaction at the Tennessee site. Trees with Pt ectomycorrhizae usually had lower concentrations of several elements in the foliage, including potentially toxic Mn, than trees with naturally occurring ectomycorrhizae. These data suggest that, on coal spoils, maximum benefit from Pt ectomycorrhizae can be obtained through selection of host genotypes known to be suited to the area and known to respond in a high degree to stimulation by the ectomycorrhizal fungus.