Three weeks to crop the grass

This Highland Cow and her mates have been moved from the field adjacent to the main driveway down to a smaller field near the river.
The grass there is quite long (quite hard to spot the calves when they were lying down) and the keepers reckon it will take the cows and their calves three weeks to clear the grass and then they will be returned to the large field where they can be seen and enjoyed by all who pass by.