Erik Shepard Farmer Mark Shepard sees perennials such as chestnuts and apples as a way to diversify his crops and protect the soil.

“Invest in the millennium. Plant sequoias,” said farmer and author Wendell Berry.

Or, if you’re Mark Shepard, plant chestnuts. For Shepard, the owner of New Forest Farm and a farming consultant, the long-lived perennial trees are a central feature in the ideal farm landscape. Annuals — i.e. corn, soybeans, and many other vegetables that have to be planted and harvested every year — are labor-intensive and come with steep environmental costs such as erosion, soil degradation, and nutrient runoff. So permaculturists like Shepard see planting fruit and nut trees and other perennials — which only need to be planted once, and then, once mature, continue to produce year after year — as a key to sustainable food systems. His 106-acre farm in southwestern Wisconsin is filled with hazelnuts, chestnuts, pine nuts, currants, berries, apples, and much more.