State and local laws vary, but in most cases, you are allowed to trim any branches from your neighbor's tree that cross your property line. However, it's important to ensure you do not damage the overall health of the tree in the process. Removing branches incorrectly can jeopardize the health of the tree and could lead to you being on the hook to replace it.

Deciduous shade trees (the type of trees whose leaves fall off in autumn) need to be pruned in late winter—between February and March. That’s because it’s easier to find and remove sick or dead branches when no leaves are present. And wounds close and heal faster in colder temperatures so pruning them at this time also makes them less prone to infection.

Not all evergreen conifers need to be pruned, but some do. Pruning pine trees is not necessary, but you can do so during June and July if you wish. On the other hand, spruce, firs, and junipers do need to be pruned from late winter to early spring.

Tree experts don’t advise against digging through tree roots, but instead encourage caution and consultation with a local arborist to make sure you don’t damage the tree’s structure or interrupt its water or nutrient intake. An arborist can recommend specific practices when digging and help prune the roots or dig a trench for utilities with a tool that can remove soil without touching the tree’s roots.