New England's Roadside Ecology with Tom Wessels

Notable Terms to Learn:

"Root Graft" - in regard to trees, the term refers to morphological interconnections, i.e., growing together of contacting roots of the same tree species (self-root grafting).  Among trees of different species, it is called intraspecific root grafting.  (I would assume that most of the time, these interactions happen below the surface.)

Along these same lines, natural limb-grafting and trunk-grafting can take place as well, in places where limbs and trunks have been in close contact for years (perhaps decades).  (I have photos but finding them is another issue.)

"Callus Wood" - The initial growth response to a tree wound, from storm damage or tree cutting.  If the tree is healthy, then the Callus becomes overgrown with "Woundwood" (in which the cells have become more specialized (differentiated and lignified).  In the Figure 1 image, the light-colored ring around the cut area is likely the "Woundwood".

Figure 1.

Here is a good article on the subject.  Here is an online discussion.

"Woundwood" - When Callus cells become differentiated and lignified.

Arborist (Arboriculture) discussions.

Beginning a Forestry Library: