Red Fern Farm
Page Last Updated: January 18, 2003
Potential Crop-producing Trees, Shrubs, and Vines for the Midwest
Windbreaks, field shelterbelts, and riparian buffer strips provide a number of well-demonstrated benefits, including increasing crop yield, soil, water, and energy conservation, and creation of wildlife habitat. A farmstead windbreak can significantly increase property values. The aesthetic benefits alone make them worthwhile.
Even with all these advantages, windbreaks and shelterbelts are not planted as often as they should be. Most landowners who inquire about cost sharing for planting windbreaks never follow through. If asked, the number one reason given is something to the effect that they don't want to or can't afford to "give up the income from that much ground."
If windbreaks and shelterbelts were composed of trees and shrubs capable of producing high value crops, then landowners could realize all of the benefits of such plantings without losing income from the land they occupy. a carefully selected and managed combination of crop-bearing trees and shrubs could fulfill all of the soil, water, energy, and wildlife functions of an ordinary windbreak and produce a far greater income for the landowner than the alternative use of the land would have.
Below is a list and brief description of some of the crop-bearing trees, shrubs, and vines which could be incorporated into a midwestern windbreak and have strong economic potential in a crop-tree agroforestry system. (For additional information on particular species, refer to Nut Growing, Ontario Style by John Gordon Jr., Available at the Wapello Public Library).
Chinese Chestnut and Hybrids
The Chinese chestnut is a medium sized tree related to beeches and oaks, with a mature height and spread of 35' to 40'. It produces a nut with a thin, leathery shell (kind of like an acorn) enclosed in a spiny bur. When ripe, the bur opens up and the nuts (usually 3 to a bur) drop out. Trees with good genetics, if grown well on a good site usually begin bearing within 3 to 5 years from planting. Chestnuts with poor genetics may not bear even after 10 years. Mature production may range from 1 to over 4 tons per acre depending on soil, climate, and management. Wholesale market value for chestnuts may range from $1/lb. to over $4/lb. depending on nut size, quality, and season. Although chestnuts are a worldwide commodity in high demand, the highest profit potential would be from local niche markets. The potential for expansion in the chestnut industry is very high. The U.S. continues to import 20 million lbs. of chestnuts annually, mostly poor quality nuts from Italy and France. There are very few domestic commercial growers and they have no trouble selling their crops at profitable prices.
In the midwest, chestnuts have no known serious insect pests, although there are problems in the East and Southeast. Chestnut blight and oak wilt may kill chestnut trees, though most Chinese chestnuts are resistant to the blight. Pruning or spraying is not needed, but some varieties need their trunks painted with white latex paint to prevent bark splitting in winter. Most chestnuts around the world are harvested by hand, and no automated machinery designed for chestnut harvesting exists. To stay fresh, chestnuts must be harvested promptly after dropping, kept cool, and kept from drying out.
Chestnut seedlings may be planted at 5'X20' or 10'X20' spacing to allow the selection of the best individuals, and later thinned to 20'X20'. After 20 or 30 years they would need to be thinned again for a final spacing of 40'X40'.
Black walnut is a large timber tree, up to 100' tall. It is valued most for its wood, but also bears edible nuts. Most black walnut nuts are very thick-shelled, have a kernel percentage around 15, and the kernel is bound tightly in the shell and is difficult to extract. A number of varieties exist which bear nuts with thin shells, higher kernel percentage (up to 40%), and easy to crack and extract the kernels.
Black walnuts are generally slow to come into bearing. A few begin by the age of 5 years, while others not until after 20. The average is probably between 10 and 15 years.
A well managed planting of ordinary black walnuts would probably average
around 500 lbs./acre/year of nut production. Individual trees with exceptional
genetics, if clonally propagated, are capable of producing in excess of 5000
lbs. per acre.
There is one company, Hammons of Stockton, MO, which buys many tons of black walnuts every year. The price they pay has averaged around 10 cents per pound (husked weight). Hammons has recently indicated they would be willing to pay a premium for high quality, orchard-produced nuts of 1.5 cents for each percent of kernel. That would make "S-127" walnuts with 40% kernel worth 60 cents per pound.
There is good potential for expansion of black walnut nut production, especially for high quality, thin-shelled varieties produced in a well managed orchard.
Black walnuts have relatively few pest of disease problems. A husk maggot and twig borer are probably the worst. Most black walnuts are harvested by hand. A company in Centerville, IA has recently developed some semi-automated harvesting and processing machinery for black walnuts.
Spacing for black walnut planting would be very similar to that for chestnuts: 5'X20' or 10'X20' at planting, and 40'X40' final spacing.
Hazels are members the birch family, and range from small shrubs to medium sized trees. The European hazel of worldwide commerce is a small tree up to 25' tall. The European hazel is not well suited to the midwest due to lack of cold-hardiness and especially to susceptibility to the disease eastern filbert blight.
A strain of hybrid hazels developed at Badgersett Research Farm near Canton, MN has commercially acceptable nut size, quality, and productivity from the European hazel, combined with cold-hardiness and blight resistance (from the American hazel) necessary for the Midwest.
Badgersett hazels are a multi-stemmed shrub from 6' to 12' feet tall. The nuts somewhat resemble acorns, but have a hard shell and are borne in clusters of 4 to 20. They are quick to come into bearing (2 to 4 years on average) and reach their mature level of production of 1 to 2 tons per acre in as few as 6 or 7 years from planting. Hazels are in high demand worldwide where they wholesale for 40 cents to $1 per pound. Higher prices would be possible in local niche markets.
There is great potential for expanding domestic hazel production, especially in the Midwest. The U.S. imports 10 times as much as it produces, and U.S. production has been dropping due to the recent introduction of eastern filbert blight in the Pacific Northwest.
Badgersett hazels are a low maintenance crop, and require no spraying or pruning. They do require high fertilization to maintain high nut production. Harvesting is currently done by hand. A harvesting machine is under development.
The heartnut is a genetic "sport" or mutation of the Japanese walnut. The Japanese walnut is a large, very spreading tree producing a round, spiny, thick shelled, hard to crack nut with little of no value. Heartnut trees produce a smooth, flattened nut shaped like a valentine heart. When cracked, the shell "pops" into two halves and the kernel comes out whole and unbroken. Heartnut trees are very fast growing and quick to come into bearing. Trees only 7 or 8 years old may already be bearing 100 lbs. of nuts. Potential production of a mature heartnut orchard is unknown (because none yet exist) but would probably exceed 10,000 lbs. per acre.
There is not yet any established heartnut industry, but growers report consumers eagerly pay $3 to $4 per pound for all the heartnuts they can get. All the heartnut trees in the world would probably cover only a few acres, so there is great potential for expansion. One problem is propagation. Grafted heartnut nursery stock is in very short supply (often with a 2 to 3 year waiting list), and seedlings of heartnuts often (sometimes up to 90%) " revert back to the wild type" if pollinized by black walnuts, butternuts, or some heartnut varieties. These will produce round, spiny nuts. (Good Heartnut varieties, when pollinized by other good heartnuts, usually produce 50% to 70% "good" seedlings).
Management of heartnuts is very similar to that of black walnuts with one important difference: Hearnuts are very susceptible to walnut bunch disease. In USDA zone 6 and farther south, the disease progresses so rapidly through the trees they are not practical to grow. In zone 5 (the southern 1/2 of Iowa), the disease is fairly easily controlled by pruning out infected branches. In Zone 4 (the northern 1/2 of Iowa), heartnuts are only marginally hardy and may suffer winter injury. This problem can be overcome by planting heartnut-shaped hybrids with butternut which are much more winter hardy.
As with any tree crop without a well established industry, harvest and handling would have to be done by hand.
Pecans are large trees, and may reach over 100' in height, and with an equal spread. They are in the walnut family along with the other hickories. Pecans can be grown in the North. They are native as far north as Dubuque, IA. There are varieties available which produce fairly large nuts and can be grown in northern zone 5 (southern 1/2 of Iowa).
Pecans are slow to come into bearing compared to some other nut trees-8 to 12 years on average. Data on production does not exist for northern pecans, but is believed to be much lower than for southern pecans.
Pecans are highly valued and in demand, but northern growers can not hope to compete on a national scale with southern growers. Northern pecans could be profitable if sold in a small, local niche market.
Plant spacing would be similar to that for black walnut and chestnut, but pecans may need to be thinned to 100'X100' after 100 years or so. Pecans require more management than most nut trees. In large plantings a number of serious insect pests and fungal diseases are usually controlled by a rigid program of spraying. Pecans also suffer from nutrient deficiencies requiring foliar fertilization. Pecan growing is a big industry in the South, and a lot of mechanized equipment for harvesting and processing is available.
Don't count on northern pecans as a big money-maker, but rather as a worthwhile part of a larger tree crops system.
Hickories (Shellbark and Shagbark) and their Hybrids
These hickories are closely related to pecans, and all will hybridize with each other. Shellbarks and shagbarks may become fairly large trees (up to 80' tall) though not as large as pecans. Both of these hickories produce a very fine flavored nut (many feel the best of all nuts), but most are too difficult to crack and extract the kernel to have much value. Several varieties exist with excellent cracking qualities, and if grafted to pecan as a rootstock may be fairly productive (hickory production is erratic at best, however). Hickory nuts of named varieties should be quite valuable in a local niche market, and one company in Michigan, American Spoon Foods, buys hickory nut kernels for $8/lb.
Shellbark and shagbark hickories are even slower to bear and less productive than pecans, but their rarity makes them that much more valuable. Plant spacing should be 10'X20' or 20'X20'.
Persian Walnut (or so-called "English Walnut")
The "Carpathian Strain" of the Persian or "English" walnut may be grown in the midwest, even into zone 4 on occasion, but it is not a very reliable tree. Even the hardiest varieties are usually short-lived, suffer high mortality, and have frequent crop failures due to late spring freezes. The frequent winter injury results in a tree with a very bushy growth form and weak branches susceptible to breakage from wind, ice, and snow. The nuts, though much more well-known, have a flavor and quality quite inferior to heartnuts. Someday more hardy and reliable varieties may be developed for the Midwest, but until then a large investment in Persian walnuts is not recommended.
"Nut pines" is a general term applied to any pines capable of producing seeds considered edible to humans. Korean pine and stone pine are two species native to Europe and Asia which do well in the Midwest. They are related to and resemble the American white pines. Pinyon pines are native to the Desert Southwest as far north as Colorado and Wyoming. They are not well-tested in the Midwest, but would be worth trying, especially on dry, sandy sites.
Nut pines produce nuts ranging in size from about like sunflower seeds up to the size of kidney beans. Pine nuts are highly valued as grommet food and retail anywhere from $10 to $20 per pound.
Nut pines are slow to come into bearing, probably at least 10 years. There is no data on per acre production, but would not need to be very high at $20 per pound to make them worthwhile. Plant spacing should be 10'X20' or 20'X20'.
The paw paw is a small tree and the only temperate member of the custard apple family. They may reach 30' tall, but mature height averages around 15'. Paw paws produce the largest fruit native to North America. The fruits resemble a small, green potato with cream, yellow or orange flesh. They are very aromatic with a tropical fruit flavor, hence the common name "prairie banana." Though research is being done to domesticate the paw paw, growers already report demand exceeds supply. Besides fruit for human consumption, additional demand for paw paws may come from the pharmaceutical industry in the future. A chemical was recently found in paw paws which has been shown to have powerful anti-carcinogenic properties. Plant spacing is 5'X20' or !0'X20'.
The American Persimmon is a medium sized tree in the ebony family. It may reach 40' tall in Iowa, but mature trees average about 20'. They are fast growing until they begin bearing fruit at 4 to 5 years, then grow slowly after that. The thin-skinned fruits are between 1'' and 2'' in diameter, and are astringent until fully ripe. When ripe the fruits are soft, even mushy, and very sweet. Their scientific name means "food for the gods."
A company in Mitchell, IN, "Dymple Delights Persimmons" buys all the persimmons they can, processes them, and sells the pulp wholesale to upscale restaurants for $8 per pint (that's $64 a gallon!). They sell out every year, and would sell a lot more if only they could get more persimmons. I would estimate one tree in Wapello produces at least 100 gallons of fruit per year.
Persimmons are remarkably free of pests and diseases. The biggest management problem is in the handling of the fruit which is soft, mushy, and difficult to ship when ripe, and hard but very astringent when unripe. Persimmons come in male and female trees, and only females bear fruit. Plant spacing is 5'X20' or 10'X20'.
The ginkgo or maidenhair tree is a genuine relic from the age of the dinosaurs. They have been around, unchanged, for at least 150 million years. Ginkgoes are related to pines, but are broadleaf, deciduous trees. They are slow growing, but may reach large size.
The ginkgo produces two potentially valuable crops-nuts and leaves. The leaves are used in the herbal supplement industry, and demand is increasing very rapidly worldwide. The 1997 wholesale price for dried leaf was $5.50 per pound. The nuts are valued in oriental communities, and may sell wholesale for $3 to $4 per pound. The nuts are enclosed in a fleshy fruit with a foul odor, and that must be removed and the nuts cleaned before they can be sold.
Ginkgoes are slow to come into bearing (up to 20 years), and only female trees bear nuts. The leaves from both male and female trees are valuable.
Hardy kiwis are rampant vines closely related to the fuzzy kiwis. Their fruits are smaller, and smooth skinned, and with a superior flavor. The vines are hardy to -25 degrees F. After 5 to 7 years, female vines come into bearing. Hardy kiwis are very productive-up to 150 lbs. of fruit per vine. One out of 6 vines need to be male to provide pollen. Enough demand exists for some fairly large plantings to be going in, mostly in the Pacific Northwest. There is no reason we couldn't grow them here in the Midwest.
The medlar is a small tree or large shrub native to Europe and Asia. Botanically, it is between a pear and a hawthorn. The fruit is about the size of a golfball, is hard until ripe, then becomes soft and mushy. The ripe fruit has the flavor and texture of spiced applesauce. Medlars were very popular in Medieval Europe, and are experiencing a resurgence in popularity. A niche market consisting of madrigal dinners would be possible.
The Traditional Fruits (Apples, Pears, Peaches, Cherries, Blueberries, Grapes, and Bramble-berries)
These are the very familiar and common crop trees/shrubs/vines of commercial orchards and berry farms. These may also be incorporated into windbreaks and shelterbelts. All of these plants require intensive management, including annual pruning and extensive spray programs. Some also require very special soil conditions. There are already a lot of growers for these crops, competition between growers is heavy, and profit margins are tight. Cherry growers in Michigan have been selling their crops for a loss for several years. On the plus-side, practically everyone is familiar with these fruits, and they may sell well in local markets.
These are just a few of the potential crop-producing trees, shrubs, and vines which could be incorporated into Midwestern windbreaks, shelterbelts, and riparian buffer strips. If these don't provide enough choices, a little research could probably come up with many more.