Okay, as someone with their doctorate in plant health (specifically trees and landscape plants), I'm frothing at the mouth livid.
Pollarding is a type of pruning done where you remove the upper branches of a tree with the intent of forcing it to grow more branches. Historically, it was used to produce fodder for livestock and wood for fencing, crafting, etc. but now is more of an aesthetic choice - it creates dense shade and reduces the risk of heavy branches becoming safety concerns later.
However, that pruning is something that occurs in January - March, when the tree is dormant. Not in the peak of summer, when there's a heat wave expected. By doing it during dormancy, the tree has already stored all of the nutrients and sugars the leaves held in the roots and trunk, ready for use in spring.
By pruning these trees now, they've severely damaged them, if not outright sentenced them to death. Leaves provide a tremendous amount of shade to the trunk, actively cool the area through respiration (pulling water through the tree and into the air around it), and provide sugars and nutrients necessary for growth through photosynthesis. These trees now have to work overtime to compensate and re-grow and entire canopy of leaves with reduced resources.
These trees are in what are sometimes affectionately known as "hell strips" - there's a concrete sidewalk on one side, asphalt on the other, and they get hot. Not just upwardly hot, but they heat the soil underneath them as well. The root zone of these trees don't get a lot of water to begin with (concrete and asphalt don't let water in well) and it doesn't seem like there's a lot of soil around the tree to begin with.
Trees in hell strips already have the heat and restricted root zones working against them - you can't have healthy trees if you don't have room for roots. Now these have to compensate and draw resources to push out new growth.
In addition, all of those pruning cuts are open wounds - places where infections and insects can enter into the tree. Usually mature trees can manage minor infections or infestations with no issue. But these trees are now extra susceptible because their immune response is weakened - all the extra energy available is going to new growth, not fighting off infections.
So there's a bunch of factors here that have put these trees at a disadvantage: the removal of most photosynthetic plant material, an increase in surrounding temperature, a restricted root zone, the potential for increased infection, and a heat wave expected in the next week. These trees are going to struggle the rest of their lives because of the decision to prune these trees like this now - all over a desire to break a strike so the studios don't have to pay their actors and writers and editors fairly.
I hope they get the book thrown at them with tree law. And then some.
