Daily Life in the Old Regime337and northern Germany, short and rainy summer seasons
severely limited the crops that could be grown and the
population that could be supported. Irish peasants dis-
covered that just one acre of potatoes, planted in soil
that was poor for grains, could support a full family.
German peasants learned that they could grow potatoes
in their fallow fields during crop rotation, then discov-
ered an acre of potatoes could feed as many people as
four acres of the rye that they traditionally planted.
Peasants soon found another of the advantages of the
potato: It could be left in the ground all winter without
harvesting it. Ripe grain must be harvested and stored,
becoming an easy target for civilian tax collectors or
military requisitioners. Potatoes could be left in the
ground until the day they were eaten, thereby provid-
ing peasants with much greater security. The steady
growth of German population compared with France
during the eighteenth and nineteenth centuries (with
tremendous historic implications) is partly the result of
this peasant decision and the educational work of
agronomists such as Antoine Parmentier, who showed
its merits in his Treatise on the Uses of the Potato.Just as the
potato changed the history of Germany and Ireland,
the introduction of maize changed other regions. His-
torians of the Balkans credit the nutritional advantages
of maize with the population increase and better health
that facilitated the Serbian and Greek struggles for
independence.Famine in the Old Regime
Even after the introduction of the potato and maize,
much of Europe lived on a subsistence diet. In bad
times, the result was catastrophic. Famines, usually the
result of two consecutive bad harvests, produced starva-
tion. In such times, peasants ate their seed grain orMAP 18.1
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