Cats usually climb trees because they are:
Being chased by other animals
Moved to a new neighborhood and are scared or spooked by unfamiliar surroundings.
Some cats claws prevents them from climbing back down and became physically stuck. Some cats may be injured and unable to come down because the predator they are trying to escape is still in the area. If the cat is simply too high up or just too scared to come down you can call the fire department and ask if they can come and help to rescue the cat from the tree.
You can also contact the arborist, tree service or animal rescue. Be sure you tell them if the cat is friendly or fearful.
Also tell them if the tree is on your property or a neighbor's property.
Professional Pet Sitting Services offered in the Upper to Mid-Pinellas County Area