Mister Dobbins made some excellent observations. You can read more about this in his book “Great Teachers”. But let’s put on our thinking caps here and analyze this realistically.
Would you really
want to make your “dirthole” to be the imitation of where a fox buried a food catch? I doubt it. Read the book. Charles once watched a fox (through a spotting scope) bury a piece of food. Charles went to find that buried food -- and could not find it. He knew within just a few feet where that food was buried, and he could not find it. The fox does not leave a “hole”. Using its nose, it flattens the ground out over top of the buried food.
So, if you are interested in making an “undisturbed” fox food cache set, forget about visual attractors. The set should be invisible when you are done. Also burying the food keeps the odors from dispersing so readily. So you better make sure you are exactly and tee-totally on location with this set. The target animal is going to have to walk right over top of it to find it. Remember, the fox is trying to hide this food so other animals cannot
find it. From a trapper’s standpoint, making a set so the animals can’t find it is counter productive.
The typical dirthole, the one that looks like a hole
is an imitation of where a fox dug up a food cache
. So, the simple visual presence of the hole, is already an indicator that the food has been dug up. I don’t think the absence of urine changes the perception of that.
But the main thing to consider here is the universal attractive power of urine in canine trapping. You can squirt urine on a plain old rock or a plain old stick, and make a set out of that. And you can squirt urine on a plain old hole, and make that an attractive set for canines as well.
That said, I personally don’t use urine on every dirthole set I make. I just don’t think it is necessary. But sometimes I do use it because I really don’t think it hurts anything. In other words, I don’t think the presence of urine will cause an animal to not investigate