What Causes the Crooked Growth of Trees on the Saskatchewan Hillside?

AI Thread Summary
Tree growth on hillsides primarily remains vertical due to the combined effects of gravitropism and phototropism. Gravitropism, influenced by gravity, dictates the upward direction of growth, while phototropism allows plants to orient themselves towards light, often resulting in angled growth when light sources are uneven. Plant hormones, particularly auxins, play a crucial role in these responses. Environmental conditions can also significantly affect tree growth patterns, leading to phenomena like krummholz and flag trees, which are adaptations to harsh climates. Specific cases, such as the peculiar growth patterns observed in certain forests, may be attributed to past environmental stresses like heavy snowfall or even genetic mutations, as seen in Saskatchewan's Crooked Bush. Overall, the interplay of gravity, light, and environmental factors shapes how trees grow, even in challenging conditions.
hagar
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When a tree grows even at an angle on a hill side it mostly remains vertical . What is at play here to cause the vertical direction of growth ?

Thank you,

Pat Hagar
 
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I bet it is something simple, such as the influence of gravity.
 
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And this shows that they may be able to grow wherever possible.
 
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Thanks to all for the information. The links were very informative. It would seem the behavior is controlled by both gravity and light however I have a difficult time considering gravity "simple", lol.

Respectfully,

Pat Hagar
 
Silicon Waffle said:
And this shows that they may be able to grow wherever possible.
That is just odd. The guy must have been shining a flashlight down his throat to keep it lit. Is the guy so sure he didn't just swallow a bit of fir tree and thought it was a large bug?
 
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I did not see this thread until it 'diverged' from reality.

Plants have a phototropic and a geotropic response mediated by plant hormones (auxins). In the absence of light (think germination in the soil) gravity dictates up and down for the plant. When light becomes available, it takes precendence to some extent over gravity. This is why plants under a single light source will grow toward the light -> at an angle producing more leaves and branches on the "lit" side.

Severe environmental condtions also affect growth habit.

Krumholz and flag trees are the effect of either/or salt spray and strong very cold prevailing wind direction. See the pictures here:
https://en.wikipedia.org/wiki/Krummholz

Trees in arctic conditions are often nanistic, where the tree branches die back to beneath the snow-level. So you see dwarf trees that have fat, very short branches with lots of dead wood above a foot or so. http://www.flora.dempstercountry.org/V.A.2.Salicaceae/Salix.arcti/Salix.arcti.pic5.jpg

Witches broom is a disease condition of trees that affects tree growth - it looks like a bad hair day for the tree. The wood supporting some of these growths is called burl. It is prized for bowl turners. Causes vary but usually are related to insect vectors and environmental effects. http://www.missouribotanicalgarden....ests-and-problems/diseases/witches-broom.aspx
 
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jim mcnamara said:
Krumholz and flag trees are the effect of either/or salt spray and strong very cold prevailing wind direction. See the pictures here:
https://en.wikipedia.org/wiki/Krummholz
Maybe you have the answer to a mystery I found.

Down near Point Pelee, on Lake Erie, there is a forest where a whole section of trees, most as much as a foot thick, whose trunks go straight up for about two feet, then veer 90 degrees to horizontal for another few feet, then turn vertical again. The deflections all point the same direction (I forget what compass heading).

My best guess is a heavy snowfall bent them all over when they were mere shoots, but they would have had to hold them there for several seasons to be as long as they are.

Ideas?
 
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Thanks again to all. This information adds a lot to what has already been posted.

Respectfully,

Pat Hagar
 
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Genetic mutation is the reason given for the Saskatchewan's Crooked Bush, for an aspen oddity that grows in all directions.
http://home.cc.umanitoba.ca/~remphre/crooked.shtml
 
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