Any country dweller can not live without their chainsaw. They use it for many things, especially fire wood. During the winter storms, it is the most important tool they have for any trees that feel.
What is a kerf chainsaw, well the kerf is actually the channel that is left by the chainsaw as it is cutting wood. Any chainsaw bar and chain will determine the width. If your chainsaw has a narrow kerf it is a light duty chainsaw or most likely a electric power chainsaw. These are really only good for trimming or doing light landscaping work. This type of chainsaw will not in any way stand up to cutting a tree.
So if you live in the country unless you are doing landscaping, you want to avoid this type of chainsaw.