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The "real prarie" was created by Native Americans burning trees. Trees are what happens when no humans are around (what some would call "natural").

by ciphol 5y ago

thecolorblue 5y ago
Plenty of other animals will destroy trees to keep the plains the way they are. Pretty much any large mammal will trample saplings and rub up against larger trees until they die. This is easier to see on the African plains with elephants.
R0b0t1 5y ago
Your natural history is way off. There's no trees on the prarie because it's dryer than the surrounding area and the grass fires burn the saplings before they grow. The climate of the interior US doesn't mesh well with forests.
- oska 5y ago
  I think you're overconfident in your understanding here. It's a very complex subject. Removal of trees from an area of land will result in greater dryness. Trees, in a substantial way, create their own climate and can increase precipitation.
  - R0b0t1 5y ago
    I'm aware, but where are you getting your knowledge specifically of the American plains? They were called the great plains since the founding of the country, because the settlers encountered plains, because they've been plains for approximately 25 million years: https://en.wikipedia.org/wiki/Great_Plains https://en.wikipedia.org/wiki/Great_Plains.
    - oska 5y ago
      I'm certainly no expert on the Great Plains but for a decent understanding of its vegetation history I wouldn't turn to wikipedia but instead look to see if there have been any decent pollen analyses done. After a short search I found one study [1] that said: > Nonarboreal pollen comprises between 37% and 86% of the assemblage throughout the record with the largest percentages occurring during the mid-Holocene (~8000–4000 yr BP). The pollen record also suggests that at 8200 yr BP, there was an abrupt shift from oak-elm woodland to a more open landscape of grassland or savanna, which remained through out the mid-Holocene. Additionally, the pollen data suggest that vegetation composition exhibited little change in diversity through time despite recurring fire. Charcoal concentrations varied from 30 to nearly 1200particles cm−3, indicating changes in relative amount of biomass burned, but the morphotypes of charcoal pieces indicate that woody fuels persisted during the mid-Holocene despite the apparent grassland-dominated landscape. Magnetic susceptibility in the sediment ranges from −0.9 to 22.4 (×10−5 SI) throughout the record, with the biggest increase occurring as the vegetation shifted from woodland to grassland entering the mid-Holocene. So I'd suggest that the change from oak-elm woodland to more open grassland or savanna was possibly (probably?) precipitated by the arrival of humans in North America. [1] https://www.researchgate.net/profile/Berangere-Leys/publication/281034654_Great_Plains_vegetation_dynamics_in_response_to_fire_and_climatic_fluctuations_during_the_Holocene_at_Fox_Lake_Minnesota_USA/links/561e6e1708ae50795afef889/Great-Plains-vegetation-dynamics-in-response-to-fire-and-climatic-fluctuations-during-the-Holocene-at-Fox-Lake-Minnesota-USA.pdf https://www.researchgate.net/profile/Berangere-Leys/publicat...
      - R0b0t1 5y ago
        Very interesting, I'll take another look. However if we take the paper at face value circa 8200BP there was some widespread climate event which is likely what drove the change, not people. Why I consider this paper suspect is that the mechanism that drives the modern preservation of the prarie and sometimes its encroachment into existing woodland is well understood. It doesn't require the involvement of people. It does not exist today because the grassland is gone. Lightning during the drier days of fall would lead to grass fires, burning the trees. There were microenvirons near streams that had trees but they were not common.
        oska 5y ago
        I don't think you can say the paper is 'suspect'. It's primarily factual findings of a pollen analysis. But a criticism you certainly can make is that it's just one study from one geographic location. And that's a very valid criticism and looking back, I am guilty of over-extrapolating from this one single study in one location. > Lightning during the drier days of fall would lead to grass fires, burning the trees. This is one dynamic. There are other dynamics that help (not hinder) the expansion of forests. So again, I don't think the story is so simple. > There were microenvirons near streams that had trees but they were not common. Australia also has microenvirons along water courses where tropical & temperate rainforest species are preserved. Rainforest species are much more resistant to fire as opposed to the very fire-prone (but also fire adaptive) Eucalypt species that are highly dominant across the Australian landscape. But this is a change since the arrival of man, when rainforest and other less fire-prone tree species were much more predominant. In other words, fire-prone but also fire-adaptive trees/forests were 'selected for' by humans in Australia. Trees along streams on the North American Great Plains could also just be remnants of earlier much more wide-spread forests. So you can see that I'm continuing to push the influence of humans in the diminution of forests. In many ways humans are 'the enemy' of forests (with the exception of some rainforest tribes that are highly adapted for forest living). Anyway, it's a very interesting topic and I've appreciated this exchange of views.

The "real prarie" was created by Native Americans burning trees. Trees are what happens when no humans are around (what some would call "natural").

by ciphol 5y ago

The "real prarie" was created by Native Americans burning trees. Trees are what happens when no humans are around (what some would call "natural").

thecolorblue 5y ago

Plenty of other animals will destroy trees to keep the plains the way they are. Pretty much any large mammal will trample saplings and rub up against larger trees until they die. This is easier to see on the African plains with elephants.

R0b0t1 5y ago

Your natural history is way off. There's no trees on the prarie because it's dryer than the surrounding area and the grass fires burn the saplings before they grow. The climate of the interior US doesn't mesh well with forests.

oska 5y ago
I think you're overconfident in your understanding here. It's a very complex subject. Removal of trees from an area of land will result in greater dryness. Trees, in a substantial way, create their own climate and can increase precipitation.
- R0b0t1 5y ago
  I'm aware, but where are you getting your knowledge specifically of the American plains? They were called the great plains since the founding of the country, because the settlers encountered plains, because they've been plains for approximately 25 million years: https://en.wikipedia.org/wiki/Great_Plains https://en.wikipedia.org/wiki/Great_Plains.
  - oska 5y ago
    I'm certainly no expert on the Great Plains but for a decent understanding of its vegetation history I wouldn't turn to wikipedia but instead look to see if there have been any decent pollen analyses done. After a short search I found one study [1] that said: > Nonarboreal pollen comprises between 37% and 86% of the assemblage throughout the record with the largest percentages occurring during the mid-Holocene (~8000–4000 yr BP). The pollen record also suggests that at 8200 yr BP, there was an abrupt shift from oak-elm woodland to a more open landscape of grassland or savanna, which remained through out the mid-Holocene. Additionally, the pollen data suggest that vegetation composition exhibited little change in diversity through time despite recurring fire. Charcoal concentrations varied from 30 to nearly 1200particles cm−3, indicating changes in relative amount of biomass burned, but the morphotypes of charcoal pieces indicate that woody fuels persisted during the mid-Holocene despite the apparent grassland-dominated landscape. Magnetic susceptibility in the sediment ranges from −0.9 to 22.4 (×10−5 SI) throughout the record, with the biggest increase occurring as the vegetation shifted from woodland to grassland entering the mid-Holocene. So I'd suggest that the change from oak-elm woodland to more open grassland or savanna was possibly (probably?) precipitated by the arrival of humans in North America. [1] https://www.researchgate.net/profile/Berangere-Leys/publication/281034654_Great_Plains_vegetation_dynamics_in_response_to_fire_and_climatic_fluctuations_during_the_Holocene_at_Fox_Lake_Minnesota_USA/links/561e6e1708ae50795afef889/Great-Plains-vegetation-dynamics-in-response-to-fire-and-climatic-fluctuations-during-the-Holocene-at-Fox-Lake-Minnesota-USA.pdf https://www.researchgate.net/profile/Berangere-Leys/publicat...
    - R0b0t1 5y ago
      Very interesting, I'll take another look. However if we take the paper at face value circa 8200BP there was some widespread climate event which is likely what drove the change, not people. Why I consider this paper suspect is that the mechanism that drives the modern preservation of the prarie and sometimes its encroachment into existing woodland is well understood. It doesn't require the involvement of people. It does not exist today because the grassland is gone. Lightning during the drier days of fall would lead to grass fires, burning the trees. There were microenvirons near streams that had trees but they were not common.
      - oska 5y ago
        I don't think you can say the paper is 'suspect'. It's primarily factual findings of a pollen analysis. But a criticism you certainly can make is that it's just one study from one geographic location. And that's a very valid criticism and looking back, I am guilty of over-extrapolating from this one single study in one location. > Lightning during the drier days of fall would lead to grass fires, burning the trees. This is one dynamic. There are other dynamics that help (not hinder) the expansion of forests. So again, I don't think the story is so simple. > There were microenvirons near streams that had trees but they were not common. Australia also has microenvirons along water courses where tropical & temperate rainforest species are preserved. Rainforest species are much more resistant to fire as opposed to the very fire-prone (but also fire adaptive) Eucalypt species that are highly dominant across the Australian landscape. But this is a change since the arrival of man, when rainforest and other less fire-prone tree species were much more predominant. In other words, fire-prone but also fire-adaptive trees/forests were 'selected for' by humans in Australia. Trees along streams on the North American Great Plains could also just be remnants of earlier much more wide-spread forests. So you can see that I'm continuing to push the influence of humans in the diminution of forests. In many ways humans are 'the enemy' of forests (with the exception of some rainforest tribes that are highly adapted for forest living). Anyway, it's a very interesting topic and I've appreciated this exchange of views.