Some Polish people decide to start a chicken farm. They get some chickens and plant them in the ground, headfirst. When all the chickens die, the farmers are somewhat confused, but they don't give up.
They get some more chickens, but these are planted feet-first. It takes a
little longer, but eventually the second batch of chickens die, too. They decide
to write a letter to the Polish agriculture bureau. In the letter they explain
in detail the procedures they have followed and their disappointing results.
A few weeks later they receive this reply from the bureau: "Before we can advise
you, please send us a soil sample."