You will have a hard time finding a truck you can use off road the one time per year that you need to if you don't own it. Just once per year, but you have to own the truck as most rental trucks will not allow going offroad. Likewise for towing, you will have a hard time finding a truck you can tow with (uhaul will only let you tow their trailers).

Even if you do find a rental truck you can use as truck for that one time of the year, it is common for rental trucks to already rented when you need them and so you can't get it.

So even if your need is once per year, owning your own truck that you use for non-truck tasks as well is realistically your best option.