A blonde buys two horses and she can't tell them apart. So she asks the farmer next door what to do. He says to cut one of their tails off. So she does. But then the other horse's tail gets caught in a bush and rips off. So she can't tell them apart again.
She asks the farmer for advice a second time. He tells her to cut one of the horses ears. So she does. But then the other horse gets its ear ripped in a barbed wire fence.

She is still confused. She asks the farmer what to do. He tells her to measure them.

She comes back and says, "The white horse is 2 inches taller than the black horse!"