Elk are extremely hard on fences. When they are frightened the will often forget to jump and will take the wire well into the bush. In general they seem to take down the top wire or more on a regular basis even when just crossing at their leisure. I have seen a lot of elk standing on top of the bales and eating. They tend to do their business on top of the bales and make them very unappealing to even the hungriest cows. We now have all of our hay yards fenced. We used 8' game fence and have never had any wildlife break in.
One of the biggest drawbacks to having a local elk population is the shear volume of forage they require. We have often had in the neighbourhood of 100 elk in the fields, and I believe they do the same amount of damage as an equivalent number of cows.
I could go on and on... but I'll spare you any further rants for now :wink: