Hopefully your not running stock tires on that grizzly? I always run bigger aftermarket tires. A lot more puncture resistant, more ground clearance, and way more traction. A winch is definitely a must also, many uses for it.
X2 on the kenda bear claws. They work quite well for not being over agressive.Maxxis bighorns and kenda bear claws are both good all around stockish tires with good traction.