When Mother Nature doesn’t seem to be co-operating with our agricultural system, it must be time to ask what we are doing wrong.
Do you remember a growing season where timely rains were scattered among warm sunny days from seeding through harvest? It seems a nostalgic memory, or even a myth. Lately, Mother Nature has been a difficult partner in production.
Annual cropping is filled with risks, but is especially vulnerable at seeding. This year, seeding was a challenge if not an impossibility in areas of northeastern Saskatchewan. Perennial crops, like hay and pasture, on the other hand, are less vulnerable to spring excesses.
Why are nearly all of our major crops annual plants? An annual plant can give everything it has to reproduction. It doesn’t need to save something for survival to next year. This means that an annual can usually produce more and bigger seeds. It means a quicker return on investment for the farmer. Crop breeding and selection are also quicker and easier.
What does Mother Nature do? Although we grow most of our crops as annual monocultures, natural systems are usually perennial communities with mixed species. Perennial grasses dominate native prairies, with a number of perennial broad leaved plants in the mix. Annual plants dominate only in areas where the perennials have been disturbed.
In prairie agriculture today, only forage crops and a few horticultural crops are perennial.
The idea of perennial grain crops is not new. Programs to develop perennial wheat were initiated by Russian scientists in the 1920s and by American scientists shortly after. Early efforts were aimed at reducing the costs of seeding. These programs were later redirected into increasing yield in annual crops.
The Land Institute in central Kansas has been advocating perennial cropping systems for more than 20 years. One of its goals has been to develop perennial grains. It has not been easy.
So far, perennial grains don’t yield as much as annuals. There is a trade-off in the plant between survival and yield, but this relationship is complex. Perennials may be able to make good use of post-harvest rains and of warm weather before the traditional seeding time. In recent years, both of these conditions have existed in the most crop-challenged areas of the Prairies.
There is a tradeoff for the farmer as well. Elimination of seeding costs in the second and later years would offset reduced yield losses.
The early ancestors of our annual crops were low yielding. Careful breeding and selection have dramatically increased yield. Through breeding, perennial cereal yields could also increase, but evaluating each selection can take years. We are only beginning to see results from programs such as that of the Land Institute.
Development of perennial grains has taken two directions. Perennial species can be domesticated to improve yields or else annual crops can be crossed with their perennial relatives in the hope of developing perennial grains with greater yield.
Domesticating a wild perennial is largely a process of selecting for higher yields and larger seeds. Intermediate wheatgrass may be the perennial grass with the most potential as a grain crop.
The Rodale Institute refers to this plant as wild triga. Seeds have a high protein and bran content and no gluten. Wild triga can be used as a cooked grain like brown rice, or ground as flour for muffins and cookies. Because it lacks gluten, it would need blending with other flours for use in raised breads.
After harvest, the stand would be suitable for fall or winter grazing. Other grasses with some potential include wild rye and beach wild rye. According to the Rodale Institute, wild rye was used as a food grain by the Vikings.
Crossing annual crops with their perennial relatives has been considered for a number of species. Potential crops may result from crosses between annual chickpea or soybean and their perennial relatives, or annual sunflower and its perennial relatives.
Washington State University has renewed its interest in perennial wheat. Yield increases have been achieved within the white wheat category. Hard red wheats have been more difficult.
Perennial cereal rye may be easier. Surya Acharya, from Agriculture Canada’s Lethbridge research centre, has released a perennial cereal rye. This variety is limited to forage or silage production because it produces many sterile flowers prone to ergot. It does fit for livestock feed. It is ready for silage a month before annual crops and if harvested at the soft dough stage, it has similar nutritional value to barley silage.
The rye continues to grow after the silage cut, allowing fall and winter grazing. Additional breeding will be required before a perennial cereal rye is satisfactory as a grain crop.
Perennial cereal rye illustrates two challenges to developing perennial grains beyond increasing seed size and number: there are issues of disease development when crops are not rotated; and the full advantages of the cropping system cannot be
realized without livestock.
The native vegetation of much of the Prairies is referred to as mixed grass prairie, a mixture of warm-season and cool-season perennial grasses and other species.
In warm dry areas and in warm dry years, the warm-season grasses do best. In cool wet areas and in cool wet years, the cool-season grasses do best.
This allows the perennial stand to adjust to conditions each year. It also reduces disease and insect problems that could overwhelm perennial monoculture where rotation is not possible.
Frick is the prairie co-ordinator for the Organic Agriculture Centre of Canada located at the University of Saskatchewan. She can be reached at 306-966-4975, at firstname.lastname@example.org, or www.organicagcentre.ca.