This is not the case in, say, Kansas, where the US government pays farmers to pump fossil water out of the Oglala Aquifer to irrigate unsustainable corn monocultures, which are then used for high-fructose corn syrup and animal feed. Don't get me started on farm subsidies; that's a rant for another day. Suffice it to say that relatively low-yield, low-water-need grain crops, such as sorghum, are much more sustainable than corn on the Great Plains. Sorghum has low water needs and can be grown dryland, i.e., without irrigation. (My inner carnivore is urging me to say that cattle ranching is also a good use of dry grassland.) On the other hand, corn is perfectly sustainable when it's grown in Stephan Guyenet's garden, although he says potatoes do better in our climate.
That example just makes it clear that the most sustainable crops depend on the context. The rest of this series will deal specifically with sustainable crops for the Pacific Northwest.
- Bivalves (i.e., oysters, mussels, scallops, and clams). They are near the bottom of the food chain, making them efficient and sustainable to farm. Because they feed on microorganisms present in the water, they need no supplemental feed. All bivalves are rich in heme iron, selenium, omega-3s, and vitamin B-12; oysters are also extremely rich in zinc. As a benefit, they lack a central nervous system and are therefore acceptable for some vegetarians and vegans.
- Eggs. Rich in selenium, retinol and other fat-soluble vitamins, choline, and omega-3s, eggs are also quite efficient to produce. The birds can be fed table scraps, as well as weeds and worms. The feed-egg conversion ratio is 2:1, which is very good for land animal protein. At the end of the chicken, duck, or goose's life, the bird can be slaughtered and eaten nose-to-tail. Male birds can also be raised for the table.
- Dairy, from cows, sheep, or goats. Providing retinol, fat-soluble vitamins, and calcium, this is a distant third to the more nutrient-dense eggs and bivalves. The feed ratio for cow's milk is 1:1, but dairy has a lower calorie and protein density than other animal products.
The next post in this series will discuss a sustainable meal plan for someone living in the Pacific Northwest.