Trees are living organisms that need care and help adapting to a changing environment, so I'm not surprised.
The old and magnificent trees we see today in streets and neighborhoods suffer from extreme survivor bias. Many tree species aren't even that large/long-lived as people tend to think about average trees.
There's also a strong correlation between speed of growth and longevity.
Going for the quantity approach that many of these low-effort projects do is little more than just tossing seeds out of a bag onto the ground. In the end you'll get more trees than you had before, but probably not by much, and with varying success.
The old and magnificent trees we see today in streets and neighborhoods suffer from extreme survivor bias. Many tree species aren't even that large/long-lived as people tend to think about average trees.
There's also a strong correlation between speed of growth and longevity.
Going for the quantity approach that many of these low-effort projects do is little more than just tossing seeds out of a bag onto the ground. In the end you'll get more trees than you had before, but probably not by much, and with varying success.