Chicago Dept. of Environment - City Trees Pruning Most trees need pruning. In the forest, trees are pruned by nature.
Limbs injured by lightning, wind or disease die and eventually fall to the forest floor.
If they hit other trees on the way down, that's part of the process. In a city, that's a hazard. City trees must be pruned periodically for the health and safety of those around them, as well as for the general health of the trees themselves. Before After Public Trees Trees on Chicago's parkways and boulevards are the property of the City and are maintained by the City. An urban forester will check out the problem and, if needed, order a crew to fix it.