It's allowed, but I don't recommend it, also the leaves would probably jam up the wheels and trip the person. If you are intent on going anyways, you could try it and see, and if it doesn't work you could turn around and go back
I would not as it is hilly and there are roots and rocks on the trail that could trip you
Some areas of the park could be accessed with a walker. The dirt trails would not be recommend.
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