For wind pollinated oaks, the rate of pollen migration into the stand is the most important factor governing gene flow. However, determining the significance of the resultant pollen distance distribution is problematic because of the nature of fractional paternity assignment. This study utilized starch gel electrophoresis and fractional paternity analysis to estimate rates of apparent and cryptic gene flow into a stand of red oak in central Missouri. Progeny arrays from three maternal trees and 234 putative fathers from a 4 ha stand revealed 15 of the 137 offspring resulting from gene flow into the stand. Furthermore, Monte Carlo simulations predicted one offspring to be the result of cryptic gene flow. Total gene flow, converted to Nm, was 2.0. Resultant pollen distance distributions suggest a leptokertic distribution, however truncation of individuals with ambiguous paternity prevents statistical testing. Male fertilities had no significant relationship with dbh, distance to maternal tree, and/or direction. Suggestions for statistical analysis of the pollen distribution are offered.

Figure 1: Percentage of assigned paternity for a 4 ha stand of red oak. Values in the 90+ category represent apparent gene flow events.