It takes anywhere from three to seven years for a stump to decompose on its own. This timeframe can depend on the kind of tree and your climate. The lower to the ground the stump is, the faster it rots. If you kill a tree stump with salt, boiling water, herbicide, light deprivation, or burning, the tree stump decomposes faster. 

Burning a tree stump can be effective, but it comes with safety considerations and isn’t always best for every situation. It's essential to check local regulations and assess the safety risks involved. Stumps that are near wooden structures or other non-moveable flammable objects aren’t good candidates for burning due to the risk of the fire spreading. Alternatives like grinding or a DIY stump rotting project might be safer and quicker for getting the job done.

For small trees, tree removal should take just a couple of hours to complete. Assume that a mid-sized tree will take between four and eight hours, depending on the extent of the equipment required and the health of the tree. Remember to add up to two hours for stump removal. Larger trees could take as long as one or two working days, about eight hours each.

The cost of professional tree trimming averages $460, with a typical range between $200 and $760. However, prices can be as low as $75 or as high as $1,800 depending on several factors. The size and type of the tree are major cost drivers; for example, trimming Crepe Myrtle trees costs an average of $80 to $400, while trimming giant pine trees can range from $200 to $1,800. Other factors that influence the price include the time of year, as services are often more costly in the spring. The tree's accessibility and your location also play a role, as a remote or hard-to-reach tree may increase the cost. Some professionals may offer a discount if you have multiple trees to trim.