Thanks Frankie. Its the same type situation here; lease pasture, etc....luckily, these are mama cows who are beyond their first calving, and not purebred, however, we bought our bull for a reason, and it wasn't for more Charolais influence on the calves of these cows. While its not as detrimental to the purity of this herd, the replacement heifers are due to go out there in the spring for breeding, and the neighbor's bull throws huge calves. With our small, english bred heifers, I'm quite hesitant to allow this guy to jump the fence to take care of what he considers his business. I have a feeling we'd be pulling calves until the cows come home (so to speak!) Not to mention that feeding an unwanted 2000lb + neighbor's bull during winter conditions gets a little frustrating. Maybe the answer to this dilemma is to just bring our low BW bull here to the home pasture to service the heifers and let the neighbor's bull have free reign with the lease pasture cows. At least that way we wouldn't be feeding 2 bulls to service the same small herd and would be able to make sure the heifers were bred by the right bull. Its just too bad he's a big 'ol Charolais and not an Angus, Brangus or Hereford bull. That would be a pretty good deal!
Sounds to me that after a good faith effort to make the situation right, the ultimate responsibility of keeping animals on their side of the fence rests with the owner of those animals.