"Farm joke submission" joke

A farmer goes into a farm supply store and orders two hundred chicks,
explaining to the owner that he wants to start a chicken farm. Two weeks
later, he returns to the store and buys another two hundred chicks. The
owner is curious, but doesn't say anything. The same thing happens when
the farmer returns in another two weeks for another two hundred chicks.
When he returns for the fourth time, the owner's curiousity is too much
for him, so he asks the farmer why he keeps coming back for so many chicks.
The farmer says, "Well, I guess I must be doing something wrong, but I don't
know what. I think I'm either planting them too deep or too close together."
Bemused by his lack of success, the farmer sends off a report of what he
has done to the local agricultural school, asking for advice. Three weeks
later, the reply comes back, saying simply, "Please send soil sample."