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Wild Triga
Intermediate Wheatgrass
Contributor: Peggy Wagoner, Rodale Institute Research Center, Kutztown, PA
Copyright © 1995. All Rights Reserved. Quotation from this document should cite and acknowledge the contributor.
- Common Names
- Scientific Names
- Uses
- Origin
- Crop Status
- GRAS Status
- Toxicities
- Traditional Uses
- Botany
- Taxonomy
- Crop Culture
- Ecology
- Cultivars
- Production Practices
- Harvesting Wild Triga
- Germplasm
- Collections
- Commercial Seed Sources
- Evaluations and Varietal Development
- Key References
- Selected Experts
- English: wild triga, intermediate wheatgrass
- Term used to refer to this crop as a perennial grain: Wild Triga
Term used to refer to this crop as a forage: intermediate wheatgrass
- Species: Thinopyrum intermedium (Host) Barkworth & D.R. Dewey
- Agropyron intermedium (Host) Beauvois
Elytrigia intermedia (Host) Nevski
Elymus hispidus (Opiz) Meldris
Agropyron glaucum (Desf. ex DC.) Roemer & Schultes
Family: Graminaceae
Tribe: Triticeae
Wild Triga is unique in that it is a perennial grain crop, unlike all of our
other grains which are annuals. Seeds are used as a grain for human
consumption. Grain can be ground into flour to make baked product or cooked
whole like rice. The grain has a sweet mild nutty flavor. Grain has higher
levels of protein (20.8%), fat (3.21%) and ash (2.64%) than wheat. The protein
is nutritionally limiting in lysine as is wheat, but Wild Triga has higher
levels than wheat of all other essential amino acids. In samples of
intermediate wheatgrass grain (Wild Triga) tested by USDA, no functional gluten
was found. However no tests have been conducted to determine if individuals
with wheat or gluten allergies can tolerate Wild Triga grain. Intermediate
wheatgrass is closely related to wheat and may cause similar problems.
Herbage of intermediate wheatgrass is used extensively as an introduced
cool-season forage in the USA and Canada and as a native forage in temperate
regions of the Old World.
Intermediate wheatgrass is also used as a reclamation grass for mine sites and
planted along roadways and airport landing strips for erosion control.
Old World from southern Europe through the Middle East and central Asia to
western Pakistan.
Wild Triga grain is available commercially from Den Besten Seeds, Inc., Box 896
Platt SD.
Intermediate wheatgrass seed is grown in the northern Great Plains and
intermountain western USA primarily to supply the seed industry for planting
pastures and hay crops. During the seed conditioning process, some
intermediate wheatgrass seeds lose their hulls, producing naked hull-less
grain. The hull-less seeds tend to lose viability more quickly and are
therefore not sold for planting hay and forage crops. Previously, this naked
grain represented a loss to the seed industry as it was not sold for planting.
This grain is now being sold as Wild Triga, the first commercially available
perennial grain.
Wild Triga is generally recognized as safe as a grain relative of wheat.
Levels of anti-nutritive substances such as tannins or trypsin inhibitors, are
similar to those found in wheat. None have been found at harmful levels.
Individuals with wheat or gluten allergies should use caution with Wild Triga
grain as it is a close relative of wheat.
In addition to being an important cool-season forage, wild triga grain may have
been consumed in Turkey, Armenia and the Caucasus mountains during Byzantine
times. More recently, in the former Soviet Union, efforts were made to develop
perennial wheat through wide hybridization of wheat with intermediate
wheatgrass. Problems with sterility and genetic incompatibility were
encountered. Instead, intermediate wheatgrass has since proven useful as a
source of genes for disease resistance which have been transferred to annual
wheat. In the last several years, there has been renewed interest in wheat x
intermediate wheatgrass hybrids to develop a perennial grain by Peters Seed and
Research in Oregon.
Intermediate wheatgrass (Wild Triga) is a perennial cool-season rhizomatous
grass (family Gramineae). As a member of the tribe Triticeae, intermediate
wheatgrass is related to important annual grains such as wheat, rye and barley
as well as 250 species of perennial grasses, many of which are important forage
grasses.
The taxonomic classification of intermediate wheatgrass has been unsettled for
some years. Until recently, North American botanists have classified
intermediate wheatgrass as Agropyron intermedium (Host) Beauvois. A
close relative, pubescent wheatgrass, has been classified as Agropyron
intermedium var. trichophorum. Pubescent wheatgrass shows its
pubescence on the seed heads and leaves in contrast to intermediate wheatgrass
which is glabrous. Both are considered part of the intermediate wheatgrass
species complex because they coexist in Old World habitats and are freely
interfertile.
Dewey (1984) proposed a new taxonomic classification based upon cytogenic
information, phylogeny and biological relationships. Under this
classification, both intermediate and pubescent wheatgrass are Thinopyrum
intermedium.
In addition to its area of origin in the Old World, intermediate wheatgrass is
widely adapted to inland sites in the temperate zone. In North America, it
grows throughout the intermountain west and the Great Plains from the Canadian
prairie in Saskatchewan south into New Mexico. It also grows in higher
rainfall areas east of the Great Plains to Pennsylvania and South Carolina. It
requires a period of vernalization in order to produce grain.
Differences in adaptation between pubescent and glabrous forms have been noted
in the USA. The pubescent form appears to be better adapted to areas of low
annual precipitation (200-400 mm), droughty soils and slightly saline soils.
The glabrous form is better adapted to area with 400 mm or more annual
precipitation and grows well even in relatively high rainfall areas of the
eastern USA. Intermediate wheatgrass grows from sea level up to 3000 m
elevation.
Quite a number of cultivars for use as forage grasses have been released since
1945. The most popular include: Oahe, Luna, Chief, Greenar, Reliant, Tegmar,
Greenleaf and Topar.
Seeds from any of these cultivars can be used for grain, but 'Oahe' and 'Luna'
have been the cultivars most often used due to their good seed yield and
quality and the fact that they lose their hulls somewhat easily as compared to
some of the other cultivars.
Cultural techniques to produce intermediate wheatgrass seed have been developed
by the forage seed industry. These techniques can be modified for the
production of grain. Since intermediate wheatgrass is a perennial, it can be
planted on hilly land that should not be planted to continuous annual crop
production. It can be grown in contour strip alternating with annual crops and
rotated with annuals on a five to seven year basis. The strips containing the
perennial grain will build soil and catch any eroding soil coming from the
areas planted to annuals.
The best stands of Wild Triga (intermediate wheatgrass) are established when
seeded into a weed free seed bed. With sufficient moisture, plants germinate
quickly, within 3-4 days. The optimum planting date is late summer when
warm-season weeds are not competitive. Seeding rates are between 7 and 15
pounds/acre with rows spaced 7 to 10 inches apart. Seeds within rows should be
spaced 1-2 inches apart. The lighter rate should be used in drier climates and
the heavier seeding rate in wetter environments.
This perennial grain will germinate and grow during the autumn, putting much of
its energy into the development of roots. During the winter it goes dormant
and begins regrowing vigorously in the spring. Plants will begin sending up
grain heads in June and the grain will be ready for harvest in August.
Wild Triga will produce its first grain crop about 11 months after planting.
When the grain heads begin to turn a straw color, the seeds are maturing. Wild
Triga grain can be direct harvested with a combine or it can be swathed and
combine harvested after drying. The techniques to use will depend upon the
location and weather patterns. Swathing should be done when heads are
beginning to show a slight amount of drying (a tan color). It is important
that there be no rain during the period immediately after swathing and before
harvesting the swathed material.
Direct combining should be done when the heads are completely dry and the
stalks are showing the dry tan color as well. Some grain may shatter before
this condition is attained. The maximum recovery of grain will usually be
achieved by waiting for the heads and stalks to dry. It is necessary to adjust
the combine settings to accomodate the smaller sized grain of Wild Triga.
Most of the grain will have the hulls still attached after harvesting.
Dehulling can be accomplished with any piece of equipment that will rub the
grain vigorously. A brush machine in which brushes rotate rapidly inside a
cylindrical screen is an effective dehuller.
Yields of Wild Triga are lower than those of annual grains because part of the
plant's energy goes to root production to sustain the plant over winter.
However, since production costs are lower, net profits are possible at lower
yield levels in this perennial as compared to annual grains. If yields of
500-600 lbs/A can be maintained over the course of four to six years, the
breakeven price of Wild Triga would be 6 cents/pound. Yields of 500-600 lb/A
are typical in the first year of production. Grain yields decline in
subsequent years. Appropriate management techniques can help reduce the yield
decline. Grazing intermediate wheatgrass stands in the fall after grain
harvest can rejuvenate stands by adding nitrogen through manure and provide a
secondary harvest product, the forage. Alternatively, Wild Triga can be
chiseled to rejuvenate sod-bound stands, having a dramatic positive effect on
yields without jeopardizing the stand or subjecting it to erosion.
- Western Regional Plant Introduction Office
- Washington State University, Pullman, WA 99164
- U.S. Living Collection of Perennial Triticeae Grasses
- Utah State University, Logan UT 84322
- Den Besten Seeds, Inc.
- Box 896, Platt, SD 57369
- Southwest Seed Co., Inc.
- 13260 RD 29, Dolores, CO 81323
More than 400 germplasm lines of intermediate wheatgrass were evaluated at the
Rodale Institute Research Center between 1987 and 1994 to determine growth and
grain yield characteristics. Selections of the most promising lines are being
used in several cycles of a recurrent phenotypic selection program in
collaboration with NRCS (former SCS) in Big Flats NY to develop higher yielding
well adapted varieties of Wild Triga.
- Becker, R., P. Wagoner, G.D. Hanners, and R.M. Saunders. 1991. Compositional,
nutritional and functional evaluation of intermediate wheatgrass
(Thinopyrum intermedium). J. Food Proc. and Preserv.
15:63-77.
- Jackson, W. 1980. New Roots for Agriculture. Friends of the Earth,
San Francisco, CA
- Wagoner, P., J.C. Gardner, B.G. Schatz, F. Sobolik and D. Watt. 1989. Grass
or grain? intermediate wheatgrass in a perennial cropping system for the
northern plains. North Dakota Agricultural Experiment Station Research Report
No. 108.
- Wagoner, P. 1990. Perennial grain development: past efforts and potential for
the future. Crit. Rev. in Plant Sci. 9:381-409.
- Wagoner, P. 1994. Perennial grain: a new use for intermediate wheatgrass.
New Crops News 4(2):3-4.
- Wagoner, P. 1995. Intermediate wheatgrass (Thinopyrum intermedium), p.
247-259. In: J.T. Williams (ed.). Underutilized Crops Cereals and
Pseudocereals
Lowell Den Besten, Den Besten Seeds, Inc. Box 896, Platt SD 57369. Tel. (605)
337-3318.
Tim Peters, Peters Seed and Research, 407 Maranatha Lane, Myrtle Creek, OR
97457
Martin van der Grinten, Natural Resources Conservation Service, Big Flats Plant
Materials Center, Big Flats, NY 14830. Tel (607) 562-8404
Peggy Wagoner, Rodale Institute Research Center, 611 Siegfriedale Road,
Kutztown, PA 19530 Tel. (610) 683-1442; Fax (610) 683-8548
Contributor: Peggy Wagoner, Rodale Institute Research Center, Kutztown, PA
Copyright © 1995. All Rights Reserved. Quotation from this document should cite and acknowledge the contributor.
Last update Tuesday, February 24, 1998 by aw