White oak (Quercas alba) acorns have lower tannin levels than red oak (Quercas rubra) acorns, therefore animals tend to eat the white oak acorns before red oak acorns. Animals such as squirrels and blue jays will often catch red oak acorns for later consumption when the tannin levels have lessened or when food sources are scarce. Since red oak acorns are more likely to be hauled off, cached, and forgotten about wouldn't this cause red oaks to be more widely dispersed than white oaks? By this I mean that white oak trees would be spaced closer together than red oaks.
In case anybody is curious this paper seems to answer this question.
The obvious conclusion to follow from these summaries is that acorns of RO have a significant dispersal advantage. RO acorns are dispersed greater distances from their sources, cached more often in a wide variety of environments, and even show the ability, under some circumstances, to escape partial predation. Acorns of WO, in contrast, should show short dispersal distances and may be in fact adapted for rapid germination near or under parent trees.