[throwaway8582]

Much of the Earth's surface is not suitable for growing trees, either because it's too dry, to wet, to cold, poor soil or lack of soil, etc. The article gives examples of planting in places where trees don't typically grow, on coastlines and in deserts, so it's not at all surprising that the trees planted there died. This is why I've always been skeptical of tree planting initiatives. In areas where they can survive, trees will just naturally appear on unused land, there's no need to plant them. If this isn't happening on it's own, it's probably because the conditions there aren't right for them.

[kokanee]

Some would argue that where conditions for trees aren't suitable, the solution is to build a forest there. Forests themselves are the best terraforming tool, if you can get them started by supplying the necessary nutrients, energy, and water.

I don't know how feasible it is, but using trees to transform parched landscapes is the mission of a company I interviewed at a while back called Terraformation, founded by the former CEO of Reddit.

[sitkack]

To add reference to the claim that, "forests themselves are the best terraforming tool", one can take the example of Ascension Island. With the introduction of outside trees that formed an ecological foothold, they started cooling humid air and reinforcing the soil so that other plants and trees can flourish.

https://en.wikipedia.org/wiki/Ascension_Island#Botany

https://www.bbc.com/news/science-environment-11137903

Once, This Island Had Just One Tree https://www.youtube.com/watch?v=TZPrk9IZ3Jw

[robocat]

Looking at the satellite photos, a lot of the Island is still quite barren.

Strangely enough, the Google maps satellite imagery is almost useless. Use Apple maps instead. If not on an Apple device, you can access Apple maps via https://duckduckgo.com/?q=ascension+island (note: satellite imagery is not available this way on my iDevice).

Here is another BBC article, which I think is far more balanced and talks about the negative issues of the biological cost of the planting: https://www.bbc.com/news/magazine-36076411

The last volcanic eruption was 1508 or so. I did a quick Google to find some information on how long takes it generally takes for vegetative regeneration after volcanic eruptions. Looks like it depends on type of eruption and rainfall: “Mount Kelud in East Java has erupted on a 15–37-years cycle for the past centuries [snip] Within 3 years of the eruption, stem diameters were 3–10 cm. [snip] being able to establish itself rapidly in the extreme conditions that prevail after a recent ash deposition event (given the short return period of eruptions), but by enriching the ash deposits with nitrogen, paves the way for grasses to take over, which in turn delay succession to other woody vegetation” (not sure if the landscape was purely volcanically virgin). Obviously it can also takes centuries in the example of Ascension. A study in Hawaii looked at the order that types of vegetation took hold: https://www.nps.gov/parkhistory/online_books/science/5/chap8...

[jandrese]

The caveat with this is the forests can do ok for awhile, but then a dry spell will hit and it tends to burn down.

[0000011111]

I wonder what the success rate would be if trees were replanted in forest that burned.

And to what extent climate change would make the environment no longer suited for trees?

In the US forest fires burn about 7 million acres on average each year.

https://sgp.fas.org/crs/misc/IF10244.pdf

https://en.wikipedia.org/wiki/List_of_California_wildfires

The Dixie fire alone was about 1 million acres.

San Francisco is 30,000 acres for perspective.

https://sgp.fas.org/crs/misc/IF10244.pdf

[perrygeo]

> trees will just naturally appear on unused land, there's no need to plant them. If this isn't happening on it's own, it's probably because the conditions there aren't right for them.

That is only true if the seeds can travel to get there! Moving many miles or uphill via seed dispersal is a slow process. The climate gradients and habitat pressures are moving much faster. While I agree that land suitable for forests will eventually reforest itself, if we want to do it on human timescales, we may need to kick-start the process with a seed transfer program.