Tuliptree Growth   Robert Leverett
  Mar 08, 2005 05:35 PST 

Will:

   Congratulations! As always, the Smoky Mounatins are in their own
class. The growth rates are phenomenal and you've come with a whole new
growing environment for us to consider (in some way), i.e. old abandoned
logging railroads. Sheez, who would have thought? I've always admired
the tuliptree's unexcelled growing prowess, but an old railroad bed?

    The 64-dollar question is what happens to tuliptree crowns between
the ages of 70 and 150 years? The tree does not continue to grow upwards
or we would have 200 footers all over the palce in the Smokies, given
the huge acreage of tuliptrees in all age classes.

    A mutual friend of ours from Long Island, and I don't mean Ed, said
that at ages of around 70 to 80 years, the tuliptree looses some of its
apical dominance and begins to spread its crown, then undergoes typical
crown breakage, so that maximum height for the species occurs at a
relatively young age for most specimens.

    This gives ENTS another mystery to help solve. When does each
species tend to reach its maximum height? Obviously white pines are
still climbing after 150 years and in some cases after 300. I suspect
there is a greater difference among species as to when they reach their
maximums than we usually think. Come to think of it, I'm unsure of what
"we usually think".

Bob