Nice Iowa Walnut

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Iowa Big Tree Guy
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Nice Iowa Walnut

Post by Iowa Big Tree Guy » Wed Feb 10, 2016 10:39 pm

Standing on the University of Iowa Campus is a large black walnut that was nominated in the Iowa Big Tree Program back in 1979. Although it has been the state champion for several years it wasn't the largest known walnut in Iowa back in 1979. It was a respectable walnut then with a circumference of 12'6''. It has grown considerably in the thirty six years since it was nominated. I measured the tree in September of 2015 and found it to have the following dimensions: Circumference - 16'10", height 92', Average crown spread 100', maximum spread 122'.

The vertical line on the trunk is the result of an old lightning strike. The wound is quite a bit wider than it appears in the photograph and the exposed wood is decaying. It has had a lightning protection system for many years but vandalism had rendered the system useless. Recently a new lightning protection system was installed so for now it has some protection. Lightning is a big problem here in Iowa and is one of the biggest factors limiting tree height.

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Larry Tucei
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Re: Nice Iowa Walnut

Post by Larry Tucei » Thu Feb 11, 2016 2:25 pm

Mark- Wow super big Walnut!! You should get some of the nuts and grow that one. We have few remaining Walnuts in all of Ms. most have been cut down. I would imagine we are in the extreme southern range of Walnut. Larry

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Re: Nice Iowa Walnut

Post by Rand » Thu Feb 11, 2016 3:22 pm

Jeez, even the limbs are big enough for saw logs. Anybody know if limbs can be used as saw timber? Or are they subject to warping because of reaction wood and/or asymmetrical growth?

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Re: Nice Iowa Walnut

Post by Don » Thu Feb 11, 2016 4:13 pm

Rand- got it! Unless they made an essentially vertical run after branching.
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