Altered disturbance regimes and novel introductions are causing rapid shifts in the
distribution of pines (Pinus L.). The functionally obligate symbiosis between pines and
ectomycorrhizal (EM) fungi dictates that shifts in the distribution of one partner will affect the
distribution of the other. In this review, we examine evidence for three hypotheses.(1) The
loss of photosynthates through stress or tree mortality decreases the abundance of EM fungi
and selects for less carbon-demanding species.(2) Pine introductions initiate establishment …