Sometime in December 2014 Tom Wahl made a claim on the Practical Farmers of Iowa list serve that 16 families could make a living farming on 160 acres using an agroforestry system. Below he gives more details on his claim. Edits have been added.
These figure comes from my own personal experience in growing and marketing chestnuts, plus yield data from the University of Missouri Center for Agroforestry and from Kansas State University. The full answer would be long and complicated. I am working on a book (to be published by Chelsea Green Co.) that will explain this all in detail, but for now I will give the “short” answer.
As you could probably guess, the most important component in my agroforestry system is chestnuts. I have been telling people for years that one reasonably fit adult should be able to manage 10 acres of chestnuts by his or herself (labor for harvesting being the limiting factor). 10 acres of chestnuts, well managed on a good site, should be able to produce 3500 to 4000 lbs per acre of nuts, for a total of 35,000 to 40,000 lbs on the 10 acres. This would be for a “mature” level of production, but that can be reached in 12 to 15 years from the initial planting. In Iowa, the nuts wholesale for $2 to $3 per pound, so the 10 acres should generate $70K to $120K per year.
That is just for chestnuts. You could put a pawpaw tree underneath every chestnut tree. Pawpaws are natural understory trees and can produce 50% to 75% of a full crop even in fairly heavy shade. Dr. Patrick O’Malley estimates that pawpaws in Iowa should bear around 14,000 pounds per acre (in full sun). Pawpaws can wholesale for as high as $7 to $10 per pound. [we plan to sell you-pick pawpaws for $4.00/pound in 2015] Under the pawpaws and chestnuts you could add shade-tolerant berry shrubs such as gooseberry, currant, and honeyberry. On the ground, in the more exposed areas, you could grow perennial vegetables such as asparagus, rhubarb, and horse radish. In the shadier areas you could add high-value medicinal plants such as ginseng and goldenseal.
Even though this takes 12 to 15 years to reach this level (and that is assuming no disasters such as extreme weather events), this does not mean there is no income leading up to this point. Chestnuts can begin bearing in as little as two years from planting, and can reach 350 lbs per acre by year 5.
I am sorry that I can’t point you to university research documenting all of these figures, but there just aren’t any universities doing this. The best university info on agroforestry comes from U of Missouri Center for Agroforestry www.centerforagroforestry.org, including a 12 page summary on chestnut growing. – Tom Wahl
Table 1 shows a conservative projected production and income for chestnuts assuming 108 trees/acre and $2/pound selling price.
Year of growth
Table 2 shows a conservative projection for pawpaws assuming 108 pawpaw trees/acre (growing under chestnut trees) and $5/pound selling price.
|Year of growth||Pounds pawpaw/acre||Gross income/acre|
|10||756-972||$3,780 – $4,860|
|11||864-1188||$4,320 – $5,940|
|14||1,404-1944||$7,020 – $9,720|
|15||1,620-2,160||$8,100 – $10,800|