A century of reforestation helped keep the eastern US cool
8 comments
·October 29, 2025imoverclocked
efavdb
Can feel the same effect here in CA. I’ve heard that in areas with more humidity the effect is much weaker though, presumably because the air has higher heat capacity or something and so doesn’t cool as quickly in the shade.
SoftTalker
I live in the Midwest US, plenty humid here in the summer but it’s consistently 5 degrees cooler in my wooded neighborhood than it is in the nearest town about 10 miles away. The effect is real.
efavdb
Interesting. I asked a friend from Texas and he said he wasn't even aware that shade was cooler until he moved out. Need more data.
Arubis
I recall a factoid from growing up in southern New England: that Connecticut had more forestland in my youth than it had a hundred years earlier, because so much agricultural land had been abandoned to nature. Presumably farmers wanted soil without an annual stone harvest.
user3939382
Apparently earthworms are a problem here. The saplings need the brush to protect them and the worms which are non native are mulching it. IIRC. If half of what I hear is happening in the Canadian forests or Amazon is true it’s sickening. Of course you have the naive and confused among us who debate or defend this abhorrent and unnecessary exploitation.
kevin_thibedeau
There used to be worms before the ice. They're just repopulating. By extension, none of the trees are native either. The natural state of the higher latitudes was mud and rock 10000 years ago.
jandrewrogers
North America did not have an earthworm ecology like Eurasia. They are an invasive animal[0] brought from Europe that creates problems for the many North American plants and ecosystems not adapted to the pervasive effects of such worms.
[0] https://en.wikipedia.org/wiki/Invasive_earthworms_of_North_A...
Anecdata: I have a plot of land in the Santa Cruz Mountains and half of it has redwood coverage and the other half is sparsely covered by much smaller species. On hot days I can go to the redwood half and get an easy 10F temperature drop.
Shade is part of the equation and so is retaining water. Once I was introduced to the idea of check dams and their role in water conservation, I started noticing how the redwoods often build their own on hilly terrain.
The landscape in a forest can be quite complex and rich.