I used to follow this quite closely, but haven't for some years now. As I understand it, the only real Asian chestnut genes in these hybrid trees are for blight resistance, the other 97% of the genes are all American chestnut (height, form, growth, etc). So they are really American chestnut trees, but with the Asian genes for blight resistance.

They do this by crossing American chestnuts (which can sometimes live long enough to produce pollen and seeds before the blight kills them), with Asian chestnut trees, growing them out and keeping those hybrids that don't get blight. Then they cross those hybrids with American chestnuts and keep the ones that don't get blight. Keep doing this -- crossing the hybrid with pure American chestnut -- until you have an American chestnut in virtually every way, except it doesn't get blight.

Some people criticize this since it isn't 100% pure American, but of course since the 100% pure tree dies from blight once it gets about 20 feet tall, it's really hybrid or say bye-bye to the American chestnut.

I moved to western Canada over 20 years ago and American chestnut trees won't survive here, so I haven't followed the lastest research on this.

I think it is great work to be doing⦠the loss of one of the key large tree species from Eastern forests in the form of Am chestnuts is truly one of the great environmental tragedies of our time⦠3% non-native genes sounds ridiculously small, so shame on those who oppose this based on that alone.

But, that being said, restoring a major component of the deciduous forest over millions of square miles sounds almost futile -- is it even possible now or should we be focusing on more pressing issues?

I don't think their goal is to restore all that forest, only to get American chestnuts back as a component of our forests and yards. The organization is doing a great thing. My only quibble is to get a seed you need to donate $300, thats the only way for individuals.

Scott

One of their major experimental farms (at Glade Springs) is about 20 miles from where I live here in Southwest Virginia. They do crossing, planting, and testing for resistance on several sites they own here. Also there are recent experimental plantings on coal strip mine sites in the process of reclamation and one in the Mount Rogers National Recreation Area. My wife and I were part of a group of volunteers that helped plant on the strip mine sites last year in the late Winter. Nearly froze to death. Apparently the remains of strip mines are conducive to the growth of American chestnuts despite the fact that they are very rough and rocky with not a lot of soil.

I hear they are up to a 15/16 American now. I planted 150 Dunstan chestnuts last year and 180 this year.

Well, there's also the American Chestnut Cooperators' Foundation - a group working toward the same goal - but using only pure American chestnuts which have demonstrated some degree of blight resistance in their breeding program.
Membership/participation costs are significantly lower, as well.

Here is a link that might be useful: ACCF

This post was edited by lucky_p on Thu, May 1, 14 at 12:18

I suggest contacting Bob Stehli, a commercial chestnut grower and nurseryman in Ohio. He really knows chestnuts. His website:

http://wintergreentreefarmohio.com/chestnuts/

Marc

Great info, thanks. Very interesting.