This lets the deer stay in their normal feeding pattern undisturbed. Rest assured that once a big buck realizes that someone is keeping a close eye on him, he is likely to wait until after dark to get his groceries or he may even abandon the food source completely. When you locate a good buck using a field, either set up a ground blind ambush along a well-traveled trail or stalk the buck as he works his way to the field's edge. The biggest bucks will stay out of sight until just before dark so backtracking from the actual food source is often better than waiting directly over the field. If you use good optics to scout the property you hunt and tune your bow for accurate shooting at long range, you should be able to get a shot at a big-eared buck.
Big bucks are never easy with archery gear and old mule deer bucks are especially difficult.
If you fill your tag with a big mule deer buck you've earned one of bowhunting's toughest trophies. He shot his first deer with a bow when he was 15 and hasn't missed a Texas bow season since then.