I remember reading a book when I was younger, about a girl who was separated from her family during the Westward Migration, and forced to live on her own in the wilderness of early spring in 1860s America (unfortunately I don’t remember the name of the book). At one point in the adventure, the young heroine came upon an abandoned Indian settlement, where she was able to find some place to live (torn and tattered but protection from the elements), as well as meager amounts of grains left behind in the food storage cave (enough to make a few meals). She found corn, wheat, etc. and proceeded to make herself some gruel; after she finished eating her fill, she realized in dismay that she had used the entire supply of corn, and therefore would not be able to set aside any seed to plant for the upcoming growing season. She discovered the hard way that without planning, sustainability is endangered.

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