Mast (botany) Mast seeding is defined as the highly variable production of fruit by a population. These intermittent pulses of food resources drive ecosystem-level functions and forest dynamics. The difference between a mast seeding year and a non-mast seeding year can be thousands of acorns, hickory nuts, beech nuts, etc. Mast seeding dominantly occurs in wind-pollinated tree species, but has also been observed in grasses and Dipterocarps. Masting, in the strict sense of the term, occurs only in monocarpic (or semelparous) species, whose members reproduce only once during their lifetime, then die. Hypothesis for the evolution of mast seeding can broadly be
Beech bark disease to spread to the south and west. The first case of beech bark disease in the United States was reported in 1929 in Massachusetts. By 2004, the disease had spread as far west as Michigan and as far south as western North Carolina. For beech bark disease to occur, two components are required, an insect and a fungus. The beech scale insect, "Cryptococcus fagisuga", is invasive to North America and is host-specific, feeding exclusively on beech trees. It can be observed on the trunk and limbs of the tree as woolly, white tufts that will later develop into broad strips.