It depends on where you live—but in most areas, leaves begin falling in September and continue falling until January or February. Warmer regions, such as Southern states, may see leaves fall a bit later in the calendar year. It also depends on the type of trees in your yard and their maturity. 

It is possible to cut down a tree on your property yourself, but it is generally not recommended unless specific conditions are met. You should only consider this project if the tree is small (e.g., under 4-5 inches in diameter and short enough that you don't need a ladder to reach the branches), and you are experienced in handling a chainsaw. The tree must also be located far from any power lines, fences, homes, or other structures. Even for small trees, the work can be dangerous, and it's always advisable to have a spotter to ensure the tree falls correctly and no branches fall on you.

For any tree that is large, requires a ladder to access, or is near electrical lines or structures, you should always hire a professional. Attempting to remove a large tree yourself is extremely dangerous, poses a risk of serious injury, and could result in significant damage to your property.

Before any tree removal, it's also important to check your local and state regulations to ensure the tree is not historic or otherwise protected by your city.

There are many signs that a tree is diseased or dying, and if you suspect that’s the case, you should call an arborist immediately. You might notice rot or fungus on the trunk or that the tree is beginning to lean to one side. Brittle branches or signs of root damage are other indicators that a tree is in trouble. If the tree is dying, it might be time to cut the tree down so it doesn’t fall.

Unfortunately, most of the time you’re out of luck if a neighbor’s tree blocks your view. You don’t have a right to a view, so if you have a tree that’s near the property line but on your neighbor’s property, you can’t cut it to be able to take in a majestic mountain or a beautiful sunrise. In some communities, however, there are ordinances protecting scenic views. Checking into your local laws can help you determine your rights in this situation.