Prof. Walker's Fun School Fourth issue
6/8

Why is that?For instance, when there are many types of the pea family together, such as soybeans, it makes the soil richer.I’m Garden Pea.I’m Clover.I’m Astragalus.I’m Soy.When there is only one species of the pea family ...All aloneIf the species is struck by a disease ...... there is nothing to enrich the soil anymore. What if various dierent kinds of plants are there?

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