Dispersal and viability of seeds from cones in tops of harvested loblolly pines
2001
Shelton, M.G. | Cain, M.D.
Seed supply is one of the most important determinants of successful natural regeneration. We conducted a study to determine the potential contribution of cones in the tops of harvested loblolly pines (Pinus taeda L.) to the stand's seed supply if trees were felled after seed maturation but before dispersal. Closed cones, collected in October 1996, were stored in wire cages with periodic removals over 2 years to determine the number and viability of extracted seeds. Storage sites were an opening in a seed-tree stand and a closed-canopy pine-hardwood stand in southeastern Arkansas. Of the initial 83 viable seeds/cone, 73% had dispersed in the opening and 63% in the closed stand by March 1997, which is considered the end of the normal dispersal period from standing trees. By October 1997, only 1 viable seed/cone remained in the opening and 5 viable seeds/cone in the closed stand, indicating rather complete dispersal or mortality of seeds by the first summer after harvest. Results indicate that cones in tops of trees cut during the 2-month period after seed maturation and before substantial dispersal can make an important contribution to the stand's seed supply, especially in reproduction cutting methods where most of the trees are harvested.
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