It probably has "orchard grass" ... sheep will graze the grass down and not eat the trees. Know anyone with sheep who wants pasture?

You need to water less often, for longer periods (water for the trees, not the grass) and it will slow down the growth.

I agree with Lazygardens. You can set up a trickle arrangement to irrigate the trees, and mow the orchard with a few sheep. Word to the wise--DON'T GET GOATS!!! Goats will kill all your trees before you know it. I had a friend years ago who thought goats and sheep were interchangeable; he lost his entire orchard in 2 days.

I wouldn't trust sheep, but maybe worth a shot.
My plan for the same situation is chickens/ducks/geese. You may still need to mow, but it will be much less frequently than you would have been mowing.

A different opinion on sheep. I've seen them girdle and kill trees.

If you put pigs out there, be sure to have their noses ringed so they don't dig up all the soil.

I've put horses out in fruit trees, on a very temporary basis. No more than an hour or two. They will concentrate on the grass while they are hungry and turn into tree destroyers as soon as they are bored.

Some of the smaller geese aren't so noisy. It would take an awful lot of geese to eat 5 acres of grass.

You have horse. How about letting the grass grow and harvest it for hay?

Grow squash, pumpkins and such under them. The leaves will shade much of the grass out especially if you plant them thick. We used ground cover in part of ours. We'll also be planting Indian corn in part of it.

{{gwi:40879}}

How old is the orchard? If the trees are established, they might not need to be irrigated. At least, not so much. I have a small orchard and they have done well in the past dry years with minimal irrigation.

There is emerging research on using less water on crops and it has the potential to do two things: saving water (kinda obvious) and creating a more nutrient-dense food that tastes better (not watered down). I'm looking into this for my garden as well.

In this country, we seem to be all about bigger is better, but sometimes we can take our clues from nature and see that smaller, but more flavorful food can be better for our health and help in the quest for water conservation.