How can I distinguish red oak from white oak or bur oak?
Red oaks typically have leaves with pointed lobes as illustrated below. White and bur oak leaves have rounded lobes. There are a number of other differences between the various groups of trees with regard to bud formation, acorn shape, wood anatomy, and bark texture, but the difference in leaf structure is often sufficient to distinguish susceptible from resistant oak types in the field. How does the fungus spread from a diseased tree to a healthy one? Oak wilt can be spread between trees in two ways. First, it is well documented that most of the spread of the disease from tree to tree is by way of grafted roots. Roots of oaks growing in close proximity to each other (e.g. within 50 feet) often intermingle and eventually graft, forming functional unions that allow free flow of water, nutrients and (unfortunately) fungus spores from tree to tree. In some areas of the country where red oak is the predominant forest tree, the disease often occurs in clusters known to pathologists as “infe
