A dead tree should always be cut down, because it could fall and cause injuries or damage, and it can also attract insects like carpenter ants. A tree that’s diseased beyond repair should also be cut down, but it’s not always easy for a homeowner to tell. Signs of disease include dying branches, a hollow trunk, leaning, and discolored or missing leaves, but your best bet is to hire a local arborist who can evaluate the tree and tell you if it can be saved or should be cut down.

Yes, carefully prune back dead branches—don’t wait for pruning season. This helps keep your maple tree healthy and also helps prevent large branches from falling unexpectedly. Don’t seal the cut branch—trees can naturally take care of these wounds—but be sure to remove any source of fungus or pest infestation to help save the tree.

If it’s your property, then you can plant a tree near power lines, but it’s not the best idea. Any vegetation that grows within 10 feet or so of power lines will fall under the responsibility of the utility company, and they may trim or remove it as necessary. If you do move forward with your plan, try to choose a smaller ornamental tree, plant it as far away from the power lines as you can, and keep it trimmed to avoid future problems.

You’ll have to balance up the cost, the value of the tree (sentimental or otherwise), and the risk factors. An experienced arborist will help you understand whether transplanting is likely to be successful. The cost and hassle of transplanting a large, well-established tree are often not worth it, especially if the species is fast-growing and easy to source. The decision depends on the age and species of the tree, the conditions in the new site location, and how careful the company is when digging out and moving the tree.