Scientists and farmers working with pasture and agroforestry systems have long recognized the benefits of perennial crops that live for many years and do not require annual reseeding. Although some livestock production can be shifted to pasture-based perennial systems, humans depend upon grain. Decades of research have demonstrated that extensive planting of annual grain crops is inherently unsustainable. Although in the past plant breeders have had difficulty finding a role in sustainable agriculture, perennial grain breeding is a promising opportunity to transform agriculture. Intermediate wheatgrass (IWG) has potential to be the first widely grown perennial grain crop providing food for humans. More than 10 years of breeding IWG for grain production has already been completed, and methods for growing IWG are available. Long term outcomes of IWG grown in diverse cropping systems would include soil conservation, reduced nutrient leakage from fields, reduced pesticide application, reduced farmer input costs, and improved quality of life for society as a whole through improved natural resource conservation and wildlife protection. The next critical step toward widespread use of IWG is the expansion of a breeding program functioning within a community of practice consisting of farmers, researchers, millers, and bakers.
In two cycles of plant breeding, we doubled seed size of IWG and its average seed yield per head. In on-farm trials we identified key limitations for establishment and production, enabling greater success in later years. Experimental milling and baking produced promising results. Due to increased knowledge of the crop, additional research is beginning at institutions throughout the country.
Annual grain crops comprise a large and essential portion of the human diet, but the large-scale production of grains required to meet human food needs inevitably results in soil erosion, nutrient loss and subsequent contamination of waters, and pesticide contamination. Organic and no-till practices are among the most sustainable approaches to small grain production. However, organic systems depend on tillage for weed control and can experience soil loss through erosion and nitrogen loss through leaching into groundwater. No-till small grain systems require herbicides and often allow leaching of high levels of nitrogen into groundwater. Unfavorable weather and other uncontrollable factors often disrupt methodologies that rely on cover crops, rendering such approaches unreliable. As a perennial small grain crop, IWG would drastically reduce nitrogen loss by leaching, soil loss through erosion, and the need for tillage or herbicides for weed control. This potential comes at a time when farmers’ input costs are at an all-time high (especially that of nitrogen fertilizer, much of which escapes the root systems of annual grains), and nitrogen contamination of ground and surface waters is a serious issue facing society. Intermediate wheatgrass is an obvious choice for domestication because 1) a population is available that has already experienced a decade of selection for grain production by a joint Rodale Institute–USDA project, 2) it is widely adapted, and 3) cultural techniques have been developed in the forage-grass seed industry.
In Kansas, 60% of gross farm income comes from the sale of grain crops (USDA-NASS, 1997). Globally, more than two-thirds of all cropland is dedicated to annual grain crops (FAO, 2003). Although land currently producing grains fed to livestock could be converted to pasture, annual crops grown for human consumption will remain important in the North Central Region and internationally. In 2004, wheat was planted on 29 million acres in the North Central Region, producing 1.1 billion bushels worth $3.7 billion (USDA-NASS, 2004). A sustainable supply of small grains is critical—the average American consumes about 83 kg of wheat per year (FAO, 2002).
Although soil erosion has been recently reduced in the U.S., most of the improvement has come through taking land out of grain production rather than improving production practices. Conversion of highly erodable land to perennial cover (CRP) reduces soil erosion by an average of 17.2 tons acre-1 year-1, whereas better management of annual crops had only reduced erosion by 2.8 tons acre-1 year-1 between 1982 and 1992 (Uri, 2001). In other words, conversion to perennials is up to six times as effective at controlling erosion as is improved management of annual crops. Despite progress, soil erosion remains a major problem, causing the U.S. an estimated $37.6 billion in social costs annually (Uri, 2001).
The most effective means of reducing erosion in grain production is no-tillage practices. Unfortunately, these practices depend heavily upon pesticides for weed and disease control. The pesticides that are required in order to reduce erosion from annual crop fields have potential to harm both humans and animals. Recent findings suggest that deformities and population declines of amphibians have been due to pesticide exposure (Sparling et al., 2001; Hayes et al., 2002). In humans, pesticides have been linked to profound learning disorders (Guillette et al., 1998), childhood leukemia (Reynolds et al., 2002), birth defects, shifts in sex ratios (Garry et al., 2002), and reduced sperm counts and quality (Swan et al., 2003). According to a study by the Centers for Disease Control and Prevention (CDC) of chemicals in 9,282 people across the U.S., at least one pesticide was detected in every person studied and the average person carries a mixture of 13 of the 23 pesticides analyzed (Schafer et al., 2004). Clearly, a non-chemical approach to reducing erosion in grain fields is needed, and perennial grain crops are an attractive solution.
Globally, only about 30-50% of applied nitrogen fertilizer is taken up by annual crops (Tilman et al., 2002). Due to the lack of year-round vegetative cover, annual cropping systems can lose five times the water and 35 times the nitrogen to leaching as perennial systems (Randall et al., 1997). Not only is lost nitrogen economically wasteful, nutrients lost from annual cropping systems can pollute ground and surface waters, endangering aquatic biodiversity thousands of kilometers distant (Burkhart and James, 1999; Turner and Rabalais, 2003). Some perennials can be fertilized at a rate of 200 kg N ha-1 yr-1 and lose only 1 kg N ha-1 yr-1 to leaching (Andrén et al., 1990; Paustian et al., 1990).
The large number of funded SARE grants directed toward expanding use of perennial systems, such as pastures, is a testimony to the importance of perennials to sustainability. Perennial grain crops promise to bring the inherent sustainability of pasture systems (erosion control, nitrogen use efficiency, freedom from pesticides, and reduced input costs) into the millions of acres currently planted to annual grain crops in the North Central Region.
Intermediate wheatgrass (Thinopyrum intermedium [Host] Barkworth & D.R. Dewey) is a perennial cool season grass, originally from Eurasia, but long cultivated in North America for hay and forage (USDA-NRCS, 2004). The seed is hulled, resembling a small, slender oat seed, although free-threshing (naked) seed is present in most samples.
At least twelve improved forage varieties of IWG are currently available, enabling this crop to be grown from Washington to Pennsylvania, and Alberta to Texas. This highly palatable species frequently out-yields other cool-season forage species (Sleugh et al., 2000;USDA-NRCS, 2004), especially on fertile, well-drained soil with adequate moisture (Lawrence and Warder, 1979). Although IWG responds well to inputs and prime soils, it is also considered to be tolerant to drought, episodic flooding, acid soil, saline soil, fire, and cold (USDA-NRCS, 2004).
One reason IWG is so widely grown is that the seed has good germination and the seedlings are vigorous (USDA-NRCS, 2004). It can be planted in either the spring or the autumn in many regions, and establishes well using both no-till and conventionally prepared seedbeds (Saskatchewan Agriculture and Food, 2005;USDA-NRCS, 2004).
An explanation for the productivity and stress-tolerance of IWG across many environments is its tremendous capacity for root growth. The NRCS reports that after 5 years of growth, there may be up to 7000 lb/acre of IWG roots in the top 8 inches alone(USDA-NRCS, 2004). Even on mine spoils with no topsoil present, IWG root systems reached 20 inches (the greatest depth examined) in less than six months(Mc Ginnies and Nicholas, 1980) and at The Land Institute, one-year old plants typically produce vigorous root systems down to 72 inches and by 18 months they can exceed 120 inches (Jerry Glover, personal communication). In experiments with various ratios of mine spoils and topsoil, IWG root production always exceeded that of winter wheat (Mc Ginnies and Nicholas, 1980) and IWG exhibited strong, deep rooting even on zinc-contaminated soil (Palazzo et al., 2003).
Although not native to North America, IWG has been grown here since the 1930s, has been well-documented, and has shown no tendencies to become weedy or invasive (USDA-NRCS, 2004). It co-exists well with native plants and has no known negative impacts on wild or domestic animals (USDA-NRCS, 2004). The NRCS considers this to be a good species for building and stabilizing soil and for providing cover for nesting birds (USDA-NRCS, 2004).
Herbicides are the most commonly used pesticide globally, making up about 45 percent of the dollar value of all pesticides sold (Yudelman et al., 1998). This major category of pesticide could be sharply reduced if cropping systems could be made less invasible by weeds. Prairie restoration (planting herbaceous perennials) has been shown to reduce weed biomass by 94% (Blumenthal et al., 2003). Possible mechanisms of weed reduction in stands of perennial grasses include greater aboveground biomass throughout the season (which reduces light availability to weed seedlings), establishment limitation, presence of mutualists or antagonists, and the strong competitive effects of perennial grasses. Darwent and Elliot (1979) found that when planted in narrow rows, IWG can have a “pronounced effect” on dandelion growth. As expected, there was much less suppression of dandelions when IWG was planted in wider rows. Similarly, high-density IWG populations were able to control the invasive knapweed, but successful establishment of IWG required a very high seeding rate (Sheley et al., 1998). In general, cool season grasses have been able to out-compete weeds such as quackgrass and bindweed only when planted densely (Darwent and Elliott, 1979). In wide rows, weeds frequently invade cool season grasses unless there is cultivation between the rows (Darwent and Elliott, 1979;USDA-NRCS, 2004).
In South Dakota, soils cultivated for 50 years have typically lost 40% of their original organic matter (White et al., 1976). Farmers striving toward sustainability have typically inherited soils with similarly depleted organic matter and have a vital interest in rebuilding that organic matter. In a six-year study, IWG added 1.5 more tons/ha of soil organic carbon (SOC) than continuous wheat, and 3 tons/ha more than a wheat/fallow system. IWG has built SOC even in low-input situations (Bremer et al., 2002).
Intercropping grasses with legumes is a strategy for reducing the need for inputs of nitrogen-rich manure or compost. Adding legumes to grasses often has other benefits: increased forage yield, better seasonal distribution of forage, reduced weed invasion, reduced soil erosion, and improved stand longevity (Berdahl et al., 2001; Karnezos and Matches, 1991; Schultz and Stubbendieck, 1982; Sleugh et al., 2000). Sleugh et al. (2000) found that IWG mixed with kura clover, alfalfa, or birdsfoot trefoil gave greater yields than stands of pure IWG, even though the pure grass stands were fertilized and the mixtures were not. IWG mixed with alfalfa did especially well, yielding more than three times the forage as pure grass. Although legumes frequently come to dominate grasses in such mixtures (Berdahl et al., 2001), IWG has been found to be more competitive with legumes than other grasses (Schultz and Stubbendieck, 1982; Sleugh et al., 2000). Even IWG, however, is eventually out-competed by alfalfa, probably due to alfalfa’s deep taproots (Berdahl et al., 2001; Berdahl et al., 2004; Sleugh et al., 2000).
Moore et al. (1995) found that even modest plant breeding work on IWG produced improved strains with potential for significant impact on animal productivity. They concluded that existing cultivars have not been genetically narrowed; each contains enough genetic variation for continued plant breeding. Breeders have found significant genetic diversity for forage-related traits including yield (Vogel et al., 1986; Vogel et al., 1993), digestibility (Vogel et al., 1993), in-vitro dry matter digestibility (IVDMD) (Vogel et al., 1986), and resistance to leaf-spot (Helminthosporium sativum) (Karn et al., 1989; Krupinsky and Berdahl, 1982).
Improved pasture crops often have low, unreliable seed yield, making forage seed expensive. Therefore, forage breeders and agronomists have been interested in methods for increasing the seed yield of IWG. Knowles (1977) used recurrent mass selection to develop lines with more than twice the potential for seed yield. Importantly, he also found that breeding exclusively for seed yield did not lead to a reduction in forage yield. He determined that the yield of plants in their second year was predictive of their long-term yield, while first-year yields were not. It is therefore important to wait until the second year to select for seed yield, but not necessary to measure seed yields for many years. Confirming existing theory, he showed that controlled intercrossing of the selected plants gave greater improvement per cycle than open pollination. Selection following poly-cross progeny testing gave a greater increase per cycle than mass selection but a lower rate of increase per year since each cycle took longer.
Agronomists determined that growing IWG in wide rows greatly increased seed yield per hectare. Wide row spacing also reduces the effect of drought on seed yield and even allows certain intercrops such as flax and oats to be grown with relatively small reduction in IWG seed yield (Saskatchewan Agriculture and Food, 2005). The NRCS (USDA-NRCS, 2004) recommends planting in 24-36 inch rows, cultivation between rows, and occasional use of a sod ripper to restore productivity. Managed in this way, a stand can produce seed economically for 7-10 years. Spring burning of stubble has been found to increase subsequent seed yields and reduce some pest populations in IWG seed fields (Schaber, 1994). Saskatchewan Agriculture and Food (Saskatchewan Agriculture and Food, 2005) has published instructions for determination of correct moisture content and machinery settings for combine harvesting of IWG seed.
In the 1980s, Peggy Wagoner at The Rodale Institute identified IWG as the most promising perennial cool season grass for development as a perennial grain (Wagoner, 1990). Out of 100 species evaluated, IWG came the closest to meeting the following criteria for a perennial, mechanically-harvested grain: seed flavor, easy threshing, large seed, synchronous seed-set, shatter-resistance, strong erect seed stalks, seed heads held higher than the foliage, seed head and stalk dry-down at maturity, and a hardy perennial habit (Wagoner, 1990).
In addition to plant breeding, researchers at The Rodale Institute experimented with organic practices for raising IWG as a grain crop (Wagoner, 1989; Wagoner, 1990). After trial-and-error, they found that IWG could be reliably established in rotation following a small grain. Seed was drilled in narrow rows (7 inches) with white clover or birdsfoot trefoil instead of IWG every third row. IWG did not perform well following a legume, because weeds were better able to exploit the released nitrogen than were the IWG seedlings. Even without irrigation or manure, yields of IWG interplanted with a legume were similar to those obtained by conventional forage seed producers.
An economic analysis of IWG production for grain in North Dakota showed that while yields are less than yields of annual crops, the input costs are also likely to be less (Watt, 1989). In this analysis of likely costs and prices, an IWG grain stand persisting for 8 harvests would need an average annual harvest of 500 lb per acre for the break-even price to equal wheat. The usual yield range for forage varieties of IWG is 100-600 lb/acre. Yields of 800-950 lb/acre have been reported (Gardner, 1991; Ross, 1962).
Becker et al. (1991) found no evidence of toxicity or antinutritional compounds; the nutritional value of uncooked IWG grain was equivalent to wheat. Cooking increased the nutritional value of both grains. IWG grain had higher protein, fat and ash content than wheat, but lower carbohydrates. Products made with both types of flour had similar shelf-lives. No problems were encountered stone- or impact-milling IWG kernels. Tempering the grain to 15% moisture improved roller-mill endosperm flour yield. As expected, IWG flour is higher in bran and lower in starch than wheat flour. Hulls can be readily removed from most seeds with simple mechanical processing.
Because IWG grain contains poor baking quality gluten, it cannot be used on its own to make raised products. In addition, its high fiber content makes its whole-grain dough viscous and weak. However, bread made with 15%, banana bread made with 50%, and cookies and muffins made with 100% IWG were highly rated in a taste-test. Simply boiling IWG kernels for 20 minutes made a rice-substitute that had good texture and flavor (Becker et al., 1991).
- Generate new knowledge about the properties of IWG as a crop in sustainable farms and as a grain for human consumption. Through on-farm trials we will learn about the ways in which IWG can be most readily incorporated into farming systems. The potential for IWG to improve degraded soil, out-compete weeds, and ease transition to organic production will be documented. Food science testing will produce a detailed nutritional profile. Milling, baking, and cooking experiments will result in recommendations for end-use and a better understanding of market potential
Produce sets of improved IWG plants with larger seeds, higher seed yield, and better growth form. Breeding will produce several distinct populations with the necessary traits improved in order for IWG to become a widely grown perennial grain.
Articles about IWG as a grain will be published in regional and national magazines and scholarly journals and posted to The Land Institute website. At least three articles about IWG will be published in regional and national magazines. At least one scientific research article about IWG breeding will be published in a scholarly journal.
In the intermediate term, improved grain varieties and an expanded knowledge base about IWG will be available. Perhaps a decade of research will be required before commercially viable IWG varieties will be released to farmers. At that point, recommendations for growing IWG in diverse environments and agroecosystems will also be available.
- Spaced-plant mass selection for seed size and yield. In this selection method, 3000 individual IWG plants will be seeded in pots and transplanted into the field in the fall on 3-foot centers. The widely spaced plants will be allowed to grow the first season, but seed will not be harvested. In the second summer, seed will be harvested and threshed from each individual plant. Based on our experience in the just-completed first selection cycle, seed from 30 heads will be threshed and weighed to determine seed yield per head, and five hundred seeds will be counted and weighed from each plant to determine seed size. The best 50 plants will then be selected based on an index of seed yield per head and seed size by the gridded mass selection method. These 50 plants will be dug up and placed in a crossing block in the fall, and allowed to intermate during the third summer. The crossed seed will be harvested and 3000 plants again established in fall of the third year to start the cycle over. In three years, we will have completed one full cycle of selection.
Evaluation of selection methods. Gains made through selection in a spaced-plant nursery may not translate into performance in dense stands. To evaluate the spaced-plant breeding method, half-sib seed from 100 randomly selected plants was sown in fall 2005 in 1-row plots 7 feet long spaced 3 feet part, replicated 6 times. If plot yield and seed size correlates well with spaced plant 20-stem yield and seed size, then spaced plant selection is likely to be an effective breeding method for IWG. This experiment will also enable accurate estimates of heritability, which will help to predict future gains from selection. The same experiment will contain plots of the populations created through bulked mass selection for seed size and threshability. This will allow an accurate assessment of how quickly IWG can be improved through bulked mass selection. Data on seed yield, seed size, percent naked seed, plant height, disease resistance, and rhizomatous spread will be collected for three years.
Nutritional and Health Tests: The potential for this new grain to form an important part of a heart-disease and cancer-preventing diet will be assessed by measuring antioxidants, omega-3 fatty acids, soluble fiber, vitamins, and minerals in at least three diverse samples from on-farm trials. We will publish the full nutritional profile, which will be valuable information for anyone hoping to market IWG products. Furthermore, this data will provide baseline information for the breeding program—additional tests after several cycles of selection will inform breeders about how selection is impacting the nutritional value of the crop.
Outreach activities. Articles about the ongoing IWG research will be written by members of the community of practice, targeted to regional publications, national farm magazines, food magazines, and scholarly journals. Articles will also be posted to The Land Institute website, which receives about 5000 unique visitors per month. Some representatives of the community of practice travel extensively, giving about 40 presentations at institutions across the country per year—most of which will include discussion of IWG. More than 1000 visitors to The Land Institute receive tours annually, and IWG development will be presented to those visitors.
Bulked mass selection has produced steady increases in seed size. Six cycles of selection (which can be performed at a rate of one cycle per year) have approximately doubled seed size (Figure 1).
The mass selection breeding program, which requires the effort of harvesting and measuring each plant individually, has also been successful. Based on preliminary data, we predicted that this method would increase seed size by 13% and yield by 30% per breeding cycle. Results so far indicate that this goal has been far surpassed. The starting plants had a weight per seed of 3.2 mg. After one round of selection the size was 4.4 mg/seed, and it has now reached 6.1 mg/seed. The other major trait we have selected for is yield per head. The plants started at 0.06 g per head, were at .08 g/head after one round of selection, and are now at 0.12 g/head after two rounds of selection. Therefore, we see that for the key traits of seed size and yield, progress is exceeding or wildest expectations. Both of these traits have been doubled in only two cycles of selection. Most likely, progress was more rapid than predicted because there were a few plants containing rare genes that allowed for non-linear advances.
The large changes in seed size and yield that we have been measuring have been matched with striking changes in plant form. The plants began with slender heads with relatively few florets (see head at right in Figure 2) but now extremely large heads with numerous florets are beginning to appear in the population (see center head in Figure 2).
Selection for reduced height has also been an important part of the breeding program. In this case, the progress is taking a different route, as we have identified plants containing what appears to be a gene with dominant action that dwarfs the plants (see Figure 3, at right). This gene is being incorporated into the breeding program.
Extensive seed testing has demonstrated that intermediate wheatgrass grain is similar in vitamin and mineral content to wheat, with a few notable exceptions (Table 1). Antioxidant content also appeared to be similar. Testing of the grain revealed that it did contain proteins which would most likely make it unsuitable for consumption by those with celiac disease.
Small-scale milling and baking trials were performed by a local organic micro-baker/organic farmer. Her report is as follows:
Results of working with the milling qualities of Intermediate Wheat Grass (IWG) in comparison with Hard Red Winter Wheat (HRWW) for home use, using a small stone mill (Magic Mill) and a small steel mill (Whisper Mill):
Both mills worked equally well. The mills do heat up more with the IWG, so I was not able to mill large quantities without letting the mill cool down.
The IWG flour is moister and more golden in color than the HRWW.
The bran or outer coating of HRWW mills finer and more uniform into flour. The bran or outer coating of IWG is more difficult to mill and is coarser. For Instance:
One milling of IWG produced 65% flour with 35% bran sifted out using a 30 sieve. Milling it a second time produced 73% flour with 27% bran sifted out using again the 30 sieve.
One milling of HRWW produced 95% flour with 5% bran sifted out using a 30 sieve.
When milling just the IWG bran that had been sifted out, it produced only 24% flour and 76% bran.
Results of working with the baking qualities of IWG in comparison with HRWW:
Whole Grain Non Yeast Bakery Items: I have substituted 100% IWG for many whole grain recipes that I normally use 100% of our HRWW flour with great success in appearance, texture and flavor. The results were basically darker in appearance, moister in texture, and sweeter in flavor. I have found IWG a great substitute for 100% whole wheat in brownies, banana breads, cranberry apple breads (pretty much all sweet or quick breads), muffins, cookies, and pancakes.
Whole Grain Yeast Breads: These are a different story. I have experimented with blending IWG in different percentages with our HRWW and other whole grain flours in yeast breads. The breads have a really nice taste (sweeter, maybe even a bit nuttier) and are darker in color than breads made with 100% whole wheat. They are heavier, do not rise as well and the texture is coarser. A fairly comparable loaf of bread was produced with using about 15% IWG and 80% HRWW with about 5% vital wheat gluten.
Whole Grain Tortillas: Whole Grain tortillas made with 100% IWG are possible and actually not bad. I have tried with both baking soda and baking powder and no leavening and found the baking powder worked the best. I have also worked with different amounts of liquid (water and olive oil). The 100% IWG tortillas were easy to roll out and work with, really brown in color, and fairly pliable when warm. To make a lighter and really nice tortilla, one can substitute all-purpose white flour in different quantities for some of the IWG. I found a very nice balance was using ½ white flour and ½ IWG. It was much more pliable, folded nicely without cracking, lighter in color, very good.
On-farm trials revealed difficulties with stand establishment due to weeds, drought, and flooding. Poor yields were also obtained on-farm when available nitrogen in the soil was low. A second round of on-farm planting was done apart from this project, based on lessons learned. It was much more successful. In this new field, planting was earlier, fertilizer was used, and weeds were controlled in the first year with mowing.
The impacts of this projects in the field are expected to be large, but begin only in the medium-term once important research efforts have been completed. Therefore, the important impact of this work is not on how farming is done today, but on the future of agriculture. To that end, we strove to use this project to leverage work on domesticating intermediate wheatgrass as a sustainable perennial grain crop in institutions throughout the country and around the world. That effort has been producing rapid results. We now have collaborators at five major research institutions within the United States actively working on intermediate wheatgrass, and we are also distributing seed and plants to numerous smaller projects and collaborators. We also have growing interest from international collaborators, and have sent seed to researchers in several other nations. This is broad and growing research community, such as will be necessary to develop an entirely new crop. Undoubtedly, the work done through this SARE-sponsored effort has been a critical step toward large-scale production of this sustainable grain crop.
An economic analysis was not a part of the proposed work. This crop is still being developed through breeding, and the proper agronomic techniques await discovery. However, we are now approaching the point where preliminary economic analyses may be feasible. We have found that since intermediate wheatgrass stays leafy and green up until grain harvest, and has a higher biomass than wheat, the non-grain residue constitutes an abundant and moderate-quality hay. Also, there is opportunity for fall grazing that will exceed wheat. Therefore, in a mixed grain and livestock system, the crop could have unique economic advantage long before its grain yield approaches that of the annual crops.
This new crop is still in development and is not yet ready for farmer adoption. Nonetheless, we have been receiving inquiries from growers in the United States and Canada with interest in growing the crop. So far we have not distributed seed to farmers unless we have a research collaboration with them. We do not want farmers to attempt to grow the crop, only to have a bad experience due to the fact that the plant is genetically not yet fully domesticated.
What has been of great importance to us is what attracts the attention of farmers. First, the establishment year of a perennial (in the absence of chemical weed control) is troublesome to farmers. But in the following years, our local farmer group and others passing by have been amazed at the ability of the new perennial grain crop to control nearly all weeds without a drop of herbicide or a single tillage pass. This gets their attention and interest. Next, we have discovered that in order to appeal to grain farmers, large-acreage demonstration fields are necessary. Although we thought it would be good to involve many different farmers by having a few acres on each of their farms, we have learned that one large field harvested with a full-size combine tells the story like nothing else (see attached files).
Educational & Outreach Activities
Each year, more than 500 individuals experienced guided tours. These included some combination of the greenhouse breeding activities, the experimental plots, and the on-farm plantings. Additionally, presentations were given at dozens of locations around the country annually.
The most widely-read popular publication that included a photo and description of intermediate wheatgrass was The Furrow. Wheatgrass was also mentioned on NPR’s All Things Considered. On television, Ted Turner’s personal chef served wheatgrass biscuits on the Martha Stewart show, and there was more coverage on associated websites. This sort of popular press coverage has gone well beyond anything we anticipated, and has begun to generate a demand for both the flour and the seed from potential growers. So far, we are holding back on release of seed to the public for fear of failures and disappointment without more study first.
Some research results have been published in:
Cox, T.S., D.L. Van Tassel, C.M. Cox, and L.R. DeHaan. 2010. Progress in breeding perennial grains. Crop and Pasture Science 61:513-521.
Additional results will be reported in manuscripts that are currently in preparation.
Areas needing additional study
Clearly, the area in most desperate need of continued work and funding is plant breeding to improve the genetic capacity of intermediate wheatgrass to produce large yields of harvestable grain. This need is so urgent not because it is more important than other areas, but because of the time required. If the work is not continued over the next ten years, this potentially sustainable crop will never be developed into something useful. But if the breeding work is continued, we expect that a cultivar yielding at economic levels could be available within a decade. Then, any other remaining problems could be quickly worked on.
The next area of important research is agronomy. Establishment is an important question, but breeding for larger seed size may partially solve this problem. It is nonetheless worth considering the use of companion crops for the first year for economic benefit and weed control. Also worthy of research is the potential to use legumes as intercrops for nitrogen fixation.
Finally, utilization research must be started. At a small scale, the grain can be incorporated into many products easily. However, if it is to be grown extensively, large markets will be required. The grain will only make its way into these markets if its performance in food products is well understood.