Hazelnut and Chestnut Production
by Phil Rutter, Badgersett Research Farms
There will be a hazelnut industry in Minnesota--and Wisconsin, North Dakota, and Nebraska!
Species hybrid hazelnuts show remarkable and imminent promise for development as both a specialty crop and eventually as a full machinable agronomic staple foodstuff; in other words, "woody agriculture."
"Woody agriculture" refers to the intensive production of agricultural staple commodities from highly domesticated woody perennial plants. It differs from "agroforestry" in that no annual crops are grown, and thus little or no tillage is performed. Permanent stands of the woody crop are established, seeds harvested annually, and once every 5-10 years the wood is harvested for biomass; whereupon the plants regenerate from the roots and resume production of the food crop one year after coppicing.
The concept has been developed at Badgersett Research Farm during the past 20 years. Data on yields of specific crops indicate commercialization is now possible. No commercial scale woody agriculture planting yet exists. This is the next step necessary to make the tremendous environmental advantages of this cropping system available to farmers.
Advantages of Woody Culture
The Concept of Woody Agriculture
Use of the phrase "woody agriculture" is very recent, and unfamiliar to most. The capsule description given above is succinct, but may leave the reader with some questions. Is it really possible to grow staple food commodities on woody plants? Could woody plants be as productive as annuals? If so, why isn't it done now?
Woody plants are seldom considered for intensive development as producers of staple foodstuffs. Historically, the only trees that have contributed in a major fashion to world food supplies have been the date, oil, and coconut palms, and possibly the olive. Most trees are commonly perceived as rather unproductive, slow growing, or unreliable and seem unattractive for serious food production.
On serious examination of the dynamics of these plants, however, it appears likely that trees and other woody plants have been seriously underestimated in regard to their potential for true domestication. There appear to be several unstated and unexamined assumptions agricultural researchers commonly make about woody plants, which may in fact not hold true.
Assumption 1: Woody plants produce seed crops too erratically to be relied on for basic food production. This assumption has the invulnerability of the half-truth: wild trees commonly produce seed crops erratically. However, the evidence is very clear that this is not because consistent production is impossible, but because it is ecologically the better course for a wild tree. Experience with many fruit trees shows that consistent bearing has a large genetic component. Chestnut, in particular, belies this assumption, in that even wild stands produce good seed crops with relatively minor fluctuations.
Assumption 2: It is not possible to produce wood and food (seed) simultaneously. This assumption is again based primarily on wild or semi-domesticated trees. Research on Short Rotation Intensive Cropping (SRIC), however, has demonstrated that strains of woody plants specifically selected for maximum fiber production achieve an annual carbon fixation rate approximately three times that of one-crop maize. This means there is three times as much energy flowing through the plant.
There is no barrier to allocating this energy differently through breeding or cultural technique, so that, for example, 1/3 goes to harvestable seed, 1/3 to wood, and 1/3 to energy storage for the next season. Again, chestnuts provide a crop preadapted to these requirements: wild chestnuts produce nut crops annually, and also produce wood 30-50% faster than oaks growing in the same area.
Assumption 3: Woody plants take too long to breed. Badgersett Research Farm has bred two different lines of hybrid chestnuts that produce flowers within two months of seedling germination. This is possible with other species as well.
Ten years of research with hazelnuts and chestnuts at Badgersett Research Farm lead us to believe strongly that the potential for developing many kinds of woody plants for food production is much greater than commonly believed.
We are now ready to proceed with the development of these two crops on a commercial scale. Plantings do not resemble traditional orchards, but consist of closely spaced bushes, from 3' to 8' tall, with little or no visible space between their branches. Thus nearly all sunlight falling on the field can be captured and converted to crop.
Hazelnuts are a commodity in international trade, approximately 70% of the world crop being produced by Turkey. The nuts are about 70% oil, most of which is monounsaturated, and 20% protein. Most of the crop is used in chocolate confections, and a smaller portion is consumed in roasted nut mixes. Potential uses of the crop extend far beyond present traditions. Some hazelnut oil is marketed for human consumption, and brings extremely high prices for its lightness and flavor. The oil market presents a prime possibility for expansion. In fact, hazelnuts appear to be an excellent basic raw material, comparable to soybeans.
Chestnuts likewise have a strong existing market, some 14 million pounds being consumed in the U.S. annually, nearly all of it imported from Italy. Consumption in Europe and the Far East is very much greater. Chestnuts more closely resemble wheat or maize than soybeans, in that they have a low oil content and are high in complex starches. Chestnut flour has been used to make baked goods in Europe and the Far East for millennia, but production from the wild and near-wild plantings has never equaled the demand.
Economically Driven Change
A key point to remember is that our goal is to provide farmers with crops and agricultural practices they will want to adopt for economic reasons. If a particular crop or practice is "good for the environment" but brings no economic benefits to the farmers, relatively few farmers will change their habits and equipment.
While farmers are constantly assumed to be conservative about changing their crops, history clearly records that they respond to market forces: witness the fact that in 1930, for all practical purposes, there was no one growing soybeans in North America. Because soybeans proved profitable, however, many farmers have learned to plant and grow them, and millions of acres of soybeans are planted each year throughout North and South America.
The woody crops we are developing have the potential to be more profitable than soybeans, particularly during the early years. This is because strong markets for the raw nuts already exist-we do not have to create demand for an unknown crop. This presents the real likelihood that large plantings will be made, extending the environmental benefits of the woody agriculture practices to large areas. With foresight, as the plantings expand and traditional markets are saturated, new products and markets can be developed, exactly as was done for soybeans; allowing plantings to expand much further.
In the event that this scenario of a large scale, economically driven shift to an ecologically sounder form of agriculture can be accomplished, some of the benefits will be those outlined below.
Issues and Problems Addressed, and Potential Impacts
The possible benefits outlined here are unusually large and affect many different issues. In the case of woody agriculture, however, the benefits really could be this extensive.
The increasing fragility of the world's ecosystems and agricultural production systems is widely acknowledged. Unacceptably high soil erosion and accompanying degradation of aquifers and aquatic ecosystems, agricultural fertilizer and chemical runoff, excessive energy (fossil fuel) requirements for crop production, are all critical global problems that are in part the direct result of the universal reliance upon annual plants for the world's food supply.
Because traditional crops need to be planted every year, the soil must be tilled several times annually. Soil is thus bare and exposed to wind and water erosion throughout the time of the early growth of these crops. Even when mature, fields are susceptible to erosion because of the naked soil between plants. After harvest and through the dormant season the soil is again exposed and vulnerable. The need for tillage, cultivation, fertilizer, and pesticides means many passes through a field with heavy, energy intensive equipment. In woody agriculture, crops would be planted only once in a lifetime. The use of woody perennials for agricultural staple commodities production would result in little or no use of tillage and the presence of a permanent cover, during both the growing and the dormant seasons. Not only would this lead to a vastly lower rate of soil loss and less runoff into water supplies and aquatic environments, but to a reduced need for the fossil fuels consumed in plowing and tilling. In addition, use of pesticides needed for the establishment of annual plants could be sharply reduced. A further important benefit would be the reduction of soil compaction, since far fewer trips through the fields with heavy equipment would be required.
Stability of the World Food Supply
The vast majority of world food is now produced from a remarkably low number of crops, and often from very few varieties of those crops. This leaves humankind always at some risk, since it is always possible (indeed likely) that new diseases will develop or unfavorable weather will occur, resulting in massive food shortages.
Painful historical examples include the potato famine, the droughts in the Sahel of Africa, and nearer home the wet spring of 1989, when farmers in much of the U.S. corn belt were unable to plant their crops on time because of water saturated fields, resulting in greatly reduced yields.
Woody agriculture can contribute greatly to the stability of the world food supply in several ways. Simply introducing new staples into common use would be a great benefit: The more species are involved in food production, the more easily the food system can withstand momentary failures of any particular crop. A key goal of our work, in fact, is to demonstrate the feasibility of using woody plants for intensive food production and to directly stimulate similar domestication efforts in localities around the world, using as many different native species as possible. We already have a cooperative research program with the People's Republic of China.
In a completely different effect, woody agriculture can stabilize agricultural production because the deep permanent root systems of the crop plants are very insensitive to mild droughts or short-term flooding-both of which can cause drastic or total crop losses in annual species. This same deep root system will also much more effectively capture any necessary fertilizers; resulting both in reduced cost to the farmer and greatly reduced (or no) fertilizer runoff.
Hazelnuts have very dense nut shells that make excellent fuel; in addition, the wood from periodic coppicing will also be available for biomass fuels. This ready availability could help stimulate a renewable biomass power industry, which would decrease reliance on fossil fuels (and incidentally add another positive effect in regard to global warming, not included in the calculations above).
If the potential benefits of woody agriculture are to be realized, farmers must be convinced that they can economically grow the new crops, on land currently used to grow annual crops.
Badgersett Research Farm currently has one of the largest and most inclusive research collections of chestnut species germplasm in the world. Collections of hazelnut germplasm are more limited and specialized in material suitable to the Great Plains.
For future needs, the working collections need to be expanded to include species and varieties adapted to more circumstances. For example, it is likely that hazels adapted to very wet soils can be found in North America. This would be a useful character, as such bushes could be planted in soils subject to periodic flooding or soils that otherwise would require draining. Agricultural drainage, of course, contributes to accelerated runoff, flooding, and the degradation of wetlands. Other reasons for seeking new germplasm also exist, including genetic resistance to insect pests or other climates.
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