Identification and Sequential Occurrence of Mortality Factors Affecting Seed Yields of Southern Pine Seed Orchards

摘要

A survey of factors causing mortality of female strobili and reductions in seed quality of loblolly, longleaf, shortleaf, slash, and Virginia pines was conducted from 1973 to 1976. In general, more than half of the female strobili were lost between the flower and mature cone stages of development. Life table analyses indicated that the majority of the losses occurred during the spring of the first year of strobilus development. The primary mortality factors identified were coneworms, tip moths, loopers, the slash pine flower thrips, and strobilus abortion from unidentified causes.