A walk in the local woods gives:
Crataegus, Vaccinium--thin, smooth, exfoliating
Quercus marilandica, stellata--thick, blocky, dark
Quercus phellos, nigra--much smoother, with horizontal lines of lichen
Platanus--smooth, exfoliating
Juniperus--thin, platy, resinous
Carya--thickish, furrowed
Celtis--pink, warty
Betula nigra--exfoliating in plates
Ulmus--medium thick, medium rough
Gleditsia--smooth between the enormous thorns
Prunus--smooth
Diospyros--dark, blocky
All of these within a couple hundred yards of one another. There doesn't seem
to be any correlation with size of the plant, exposure, soil type, etc. True,
some thicker bark may provide some fire protection and some whiter bark may
cut down on sun-scald in winter, but my gut feeling is that mostly, bark
variation is provided so that botanists doing winter ID don't shoot themselves
before spring.
M. Reed, who misses smooth maples for climbing
