Some of you may remember this wildly popular thread:
https://www.adkforum.com/showthread.php?t=28030
which I snipped from another thread and continued. We again got off on the tangent of oak in the Adirondacks, somewhat unresolved, but I've learned a few things since then. Let me share.
First off, this map I posted:
Unfortunately it's a math model, not actual data. It was correlated at specific points but it was constructed for a number of genera across the US. The DEC must have somehow bought or had rights to the model. Anyway, I figured that might be important to know.
I think it generally follows a pretty good trend, but I know for a fact there are areas it's plain wrong, and I've confirmed this. For instance there are parts of Ontario county where the map should be dark green like the lower Hudson. There are pockets of oak that show up in the Adirondacks that I'm aware of that do not show up.
The second thing is what was presented by Michael Kudish, professor emeritus of Paul Smith's College. He claims the oak (and hickory actually) of the Champlain valley and encroaching the east of the Adirondacks is direct evidence that natives burned the area. I don't agree with this theory, but I'm going to put it out there.
Historical evidence does show that this area was highly agricultural, and I have no doubts that natives were highly impacting the land before Europeans. What we see today is likely the result of Europeans though. Much of this area was not included in the original blue line and the land was highly developed - a lot of it cleared for agriculture. We really don't know what was there because as hardwoods were cleared for farms, they were used to make potash or charcoal for blast furnaces. The trees simple were in the way and the timber not valuable enough or easy enough to transport for us to have much knowledge about it.
Kudish also thinks the west/central Adirondacks had not burned pre-European. This I tend to think is true and there is evidence to support. What may have burned were likely small pockets no bigger than what ice or wind my cause in terms of disturbance. Humans did clear land and cause either directly or indirectly, a number of fires in the late 1800s to early 1900s. But the interesting thing is, in most of these. We simply don't see any oak. There are a few pockets - one on Blue Mountain apparently which is pretty deep interior and some on Whiteface, that were likely started after fires.
But unlike wind dispersed species, oaks won't simply pop up out of nowhere. An acorn, and likely many acorns, need to find their way there. And I believe this dispersal barrier is why we didn't see more oak encroach after fires. The seed simply never made it there for whatever reason.
There's also the question of what else is there. In one paper I read, fire cherry was the dominant species to come in after a fire, but fire cherry seeds need to be present in the soil for that to happen. Interestingly enough their seeds can persist a century or more buried in the soil waiting for another disturbance. If a species like this is present, it's very unlikely any oak could compete for the canopy. What we see in this case is very shade tolerant species like red spruce in the understory and then becoming the dominant species as the pioneers die off.
Long story short, I still don't know why it is the way it is, but there do seem to be some indications, and most point to the fact that the seeds were simply not making it to areas where they could germinate.
https://www.adkforum.com/showthread.php?t=28030
which I snipped from another thread and continued. We again got off on the tangent of oak in the Adirondacks, somewhat unresolved, but I've learned a few things since then. Let me share.
First off, this map I posted:
Unfortunately it's a math model, not actual data. It was correlated at specific points but it was constructed for a number of genera across the US. The DEC must have somehow bought or had rights to the model. Anyway, I figured that might be important to know.
I think it generally follows a pretty good trend, but I know for a fact there are areas it's plain wrong, and I've confirmed this. For instance there are parts of Ontario county where the map should be dark green like the lower Hudson. There are pockets of oak that show up in the Adirondacks that I'm aware of that do not show up.
The second thing is what was presented by Michael Kudish, professor emeritus of Paul Smith's College. He claims the oak (and hickory actually) of the Champlain valley and encroaching the east of the Adirondacks is direct evidence that natives burned the area. I don't agree with this theory, but I'm going to put it out there.
Historical evidence does show that this area was highly agricultural, and I have no doubts that natives were highly impacting the land before Europeans. What we see today is likely the result of Europeans though. Much of this area was not included in the original blue line and the land was highly developed - a lot of it cleared for agriculture. We really don't know what was there because as hardwoods were cleared for farms, they were used to make potash or charcoal for blast furnaces. The trees simple were in the way and the timber not valuable enough or easy enough to transport for us to have much knowledge about it.
Kudish also thinks the west/central Adirondacks had not burned pre-European. This I tend to think is true and there is evidence to support. What may have burned were likely small pockets no bigger than what ice or wind my cause in terms of disturbance. Humans did clear land and cause either directly or indirectly, a number of fires in the late 1800s to early 1900s. But the interesting thing is, in most of these. We simply don't see any oak. There are a few pockets - one on Blue Mountain apparently which is pretty deep interior and some on Whiteface, that were likely started after fires.
But unlike wind dispersed species, oaks won't simply pop up out of nowhere. An acorn, and likely many acorns, need to find their way there. And I believe this dispersal barrier is why we didn't see more oak encroach after fires. The seed simply never made it there for whatever reason.
There's also the question of what else is there. In one paper I read, fire cherry was the dominant species to come in after a fire, but fire cherry seeds need to be present in the soil for that to happen. Interestingly enough their seeds can persist a century or more buried in the soil waiting for another disturbance. If a species like this is present, it's very unlikely any oak could compete for the canopy. What we see in this case is very shade tolerant species like red spruce in the understory and then becoming the dominant species as the pioneers die off.
Long story short, I still don't know why it is the way it is, but there do seem to be some indications, and most point to the fact that the seeds were simply not making it to areas where they could germinate.
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