Tallest hardwood?   abi-@u.washington.edu
  May 10, 2006 11:25 PDT 


I just returned from some fieldwork and went to remeasure the Lewis River cottonwood in Southern Washington. The tree has two different sprigs that pop above 179 feet, with the tallest being 179.6!

Since this is just May, and both leaders are thrifty, it seems likely that one or both of the leaders will be over 180 feet by September, making this, I believe, THE TALLEST NATIVE HARDWOOD IN NORTH AMERICA!!

RE: Tallest hardwood?   Robert Leverett
  May 12, 2006 05:54 PDT 

Will and Bob,

   It would be interesting to compare the density of the tall
cottonwoods in a few stands where there is one or more very tall ones to
the density of tall tuliptrees in a few stands where there is one or
more very tall tuliptrees, e.g. the best against the best to get a
better idea about averages and probabilities. Given stands of tuliptrees
and cottonwoods on comparably good growing sites for the two species and
sufficient age on the stands, are we likely to find the stand height
average to be greater for the cottonwood or the tuliptree?

   We now know that there are many places in the East where tuliptrees
break 150 feet. In fact, it has become clear that the tuliptree has more
trees in the 150 and above height class, by far, than any other eastern
species including the lordly white pine. Above 150, the tulips snake
their way into the 160s in the middle and southern latitudes and then
the species height curve takes a sharp dive. Based on what we're seeing
from our ENTS measurements, a very small fraction make it into the 170s,
but so far none have been confirmed in the 180s - although there is
little doubt in my mind that a few have done it historically. I suspect
that the high 180s represents the absolute best that the species can do.
   But back to the contest. In choosing the tallest hardwood in the
U.S., do we go with the species with the single tallest individual or do
we go with some kind of average or statistical distribution? I assume
there is a scattering of the pacific cost cottonwoods that are in the
170s and many in the 150s. Is that true Bob? Will, the gauntlet has been
thrown down. We gotta find a 180-foot tulip this summer.


RE: Tallest hardwood?   abi-@u.washington.edu
  May 12, 2006 18:36 PDT 

Bob and Will,

Open-grown cottonwoods over 150 feet tall are fairly easy to find.

Forest grown cottonwoods over 165 feet tall are super common, yet I have only measured 7 trees over 175 feet tall.

From my observations from ground-based and within-tree surveys (I have spent several days on rope in giant cottonwoods), there is a continual breakage of thumbsized twigs that goes on in the crowns of these trees. Like many Salix species, the last set of twigs before the leaves are brittle and snap off with the slightest pressure.

With these record height trees, this is probably in part due to some relationship with moisture stress, but is a feature of the trees in general.

My guess would be that your second-growth Liriodendrons that are over 170 feet tall have a better chance of reaching 190 feet than any of the Populus I am familiar with.

RE: Tallest hardwood?   abi-@u.washington.edu
  May 14, 2006 10:06 PDT 


To keep things in perspective, here is an interesting recent development.

One of my close associates, who works with me quite a bit and is quite good with tree measurements, was working on Catalina Island in southern California and measured some trees in a grove of Eucalyptus globulus. He measured several trees over 230 feet tall, with one just over 239 feet!

These trees have their roots in a stream drainage, and have sunny weather nearly every day of the year. These are easily the tallest Angiosperm trees in the Western Hemisphere! They are also not even 100 years old!

That is the good news. All of these trees are scheduled for removal because the island is trying to restore native ecosystems by removing non-native vegetation.

We will certainly try to obtain some canopy-level info before their demise, but I am not sure if we have any recourse in trying to save these extremely significant trees.