Index | Search | Home

link to pdf file

Small, E. 1999. New crops for Canadian agriculture. p. 15–52. In: J. Janick (ed.), Perspectives on new crops and new uses. ASHS Press, Alexandria, VA.


back to part 1
Part 2 of

New Crops for Canadian Agriculture—Ernest Small


Grass Pea (Lathyrus sativus L.)

Grass pea or chickling vetch is a creeping vine. It is the leading pulse crop in Bangladesh, and is also commonly grown in India, and to a lesser extent in the Middle East, southern Europe and some parts of South America. It is usually grown for grain outside of North America, but can be used for fodder. As a pulse, grass pea is very high in protein, but a neurotoxic amino acid is present in wild and most cultivated forms that if consumed in sufficient amounts can cause the irreversible crippling disease known as lathyrism. This toxin to a considerable extent has been bred out of some cultivars (although lathyrism in Asia from consuming grass pea is common). Because of its drought tolerance, grass pea has been judged to have good potential as a future new pulse crop for low rainfall areas of the Canadian prairies, occupying as much as 100,000 ha (Kiehn and Reimer 1992). In the prairies, drought strongly restricts the yield of most current pulse crops. In Canada, grass pea has been used only as a drought-tolerant green manure. 'AC Greenfix', produced by AAFC at Swift Current, was recently released. This annual legume acts as a ground cover alternative to summerfallow, helping to prevent wind and water erosion, as well as adding nitrogen to the soil. For a brief review of grass pea in Canada, see Henckes (1995).

GRASS FORAGE AND FODDER

Forage and fodder plants represent one of the best, although relatively neglected, possibilities for crop diversification in Canada. Most commercial forage production is fed on-farm to cattle, and does not capture the market spotlight. However, forages and processed hays are responsible for much of the 14 billion dollar livestock industry in Canada. World meat consumption is expanding at about twice the rate of population growth, and this has led to a two-thirds increase in world meat trade, three-quarters of this in chicken, most of the remainder in pork (Bateman 1997). Most grains and forage and fodder legumes and grasses used to feed Canadian livestock are grown domestically. There is considerable potential for increasing production of feed grains for export, but it is also sensible to concentrate on improvement of forages for the domestic livestock industry, since forages are much cheaper than grain. Forage seed production in particular recently become a growth industry in Canada, and much of this is due to associated improvements in pollination technology. In addition to benefits for livestock, forages are highly useful for soil conservation and there are some value-added opportunities.

Recent developments in grass and legume forages are documented below. There are some prospects for other kinds of forage. There has been some interest in Canada in developing native halophytes for forage, especially Atriplex species. Salt-tolerant forage could be used to exploit the widespread salinized soils in the prairie provinces. Sedges (Carex) are the dominant forage in some northern areas of Canada, and have potential for development. It was recently found that C. praegracilis Boott has some excellent nutritional properties, as well as adaptation to saline soils (Catling et al. 1994). The least-domesticated of brassicaceous crops, fodder kale and rape (Brassica spp.), have received some attention in Canada since they can provide forage well after frost, a distinct advantage in this country (Henckes 1992). This high-protein forage crop deserves more development.

Most forage grasses in Canada are improved European imports of such species as fescues (Festuca spp.), orchardgrass (Dactylis glomerata L.), timothy (Phleum pratense L.), Kentucky bluegrass (Poa pratensis L.), and smooth bromegrass (Bromus inermis Leyss.) (the latter two are circumboreal). New cultivars are regularly bred in Canada. For example, a winter-hardy orchard grass cultivar for Northern Ontario and parts of Quebec was recently released by AAFC at Ottawa. Native grasses have been referred to as a "sleeping giant," which with proper development can be enormously productive (Henckes 1992). These include bluestems (Andropogon), grama grasses (Bouteloua), bromegrass (Bromus), manna grasses (Glyceria), wheatgrasses (Elymus, and other genera depending on taxonomic concept), and other species. Slender wheatgrass [Elymus trachycaulus (Link) Gould ex Shinners] is the only native Canadian grass to have a cultivar developed for forage purposes. Cultivars of several wheatgrasses were developed at prairie stations of AAFC (Elliott and Bolton 1979). Admittedly native grasses are not generally as productive in pastures as the imported grasses, but they will outperform the latter in habitats that are marginal to agriculture. Native grasses that can be adapted to Canadian agriculture are under study at AAFC at Saskatoon and Ottawa.

Sorghum [Sorghum bicolor (L.) Moench]

Sorghum, an African grain that is a major tropical cereal, has been experimentally grown in Canada as a grain and silage crop, often as a hybrid with sudan grass [S. arundinaceum (Desv.) Stapf] for forage. Sorghum has not performed well and its future as a Canadian new crop is limited (Chubey 1983; Anon. 1985).

Use of Native Grasses for Grassland Restoration and Maintenance

Native species are used extensively in the US for revegetation, reclamation, wildlife plantings, roadside management, urban landscaping, and permanent cover. In Canada, there is growing interest in using native vegetation for waterway management, roadside maintenance and beautification, the florist and nursery trades, xeriscaping of drought-prone lands, and haylands and grazing lands. Ducks Unlimited Canada, a private, non-profit conservation organization known for its dedication to restoring and managing wetland habitats, has been a key supporter of these efforts, especially for the provision of tall, dense nesting cover for waterfowl. Efforts to date have focussed largely on the use of native grasses for the grasslands in the Canadian prairie provinces, where 70% of North America's waterfowl are produced. Traditional mixtures of introduced grasses and legumes often have not been satisfactory on a long-term basis, and the use of native grasses is increasing. Although many European and Asian grasses thrive under prairie conditions, there is a growing sentiment that native plants provide a more natural and desirable component of the prairie ecosystems. A very strong effort is underway to find and use local sources of native grasses (see Joyce 1993 for a list of species employed). Native Canadian forage grasses currently account for less than 1% of all pedigreed forage grasses grown and inspected in Canada. Although expensive and difficult to acquire in comparison with imported grasses, they are preferred by reclamation agencies to approximate original vegetation in disturbed wild lands. "Ecovar" is a recent term for ecological (not taxonomic) varieties of wild plants that have been chosen because they are particularly useful for conservation or restoration of wild landscapes. Ecovars are not necessarily artificially selected like cultivars, and if artificially selected are not greatly changed from the original populations, retaining much more genetic variability than cultivars. In theory this makes for adaptability. In Canada, there is considerable support for the use of grass ecovars to restore prairie and parkland wildlife habitats. Ecovars that stabilize duck-hunting wetlands, which are very extensive on the prairies, are particularly in demand, and although American ecovars are still predominantly used, Canadian material is becoming more important. A review of the use of wild plants to maintain and improve farm and bordering lands is Environment Bureau (1997b). Joyce (1993) reviews the use of native grasses for conservation and reclamation purposes in Canada.

LEGUME FORAGE AND FODDER

Alfalfa and the true clovers (Trifolium species) are very unlikely to be displaced as the dominant legume forages of Canada, but there are several recent additions, such as birdsfoot trefoil (Lotus corniculatus L.), and sainfoin (Onobrychis viciifolia Scop.) that are well adapted to Canadian conditions and offer good possibilities of improvement by breeding. Sweetclovers (Melilotus species) have long been used in western Canada for forage and as a honey crop, but they grow so well as weeds that they may have potential as a low-till crop. There have been continuing efforts to adapt several semi-domesticated legume forages in Canada (Crop Development Centre 1991).

Alfalfa (Medicago sativa L.)

Alfalfa, the queen of forages, is the subject of breeding research in Canada, especially in the West. Recent cultivars with high levels of resistance to verticillium wilt and bacterial wilt, main disease threats for the irrigated areas of Western Canada, are 'Barrier' and 'Blue J', produced by AAFC at Saskatoon. 'AC Grazeland' is a recent low-bloat cultivar from AAFC at Saskatoon. In Quebec, annual losses from lack of cold tolerance have been estimated to exceed $10 million, and attempts are underway by AAFC at Sainte-Foy to obtain more cold-tolerant cultivars. The use of genetically-modified alfalfa as a pharmaceutical and industrial products producer is also under study at Sainte-Foy. The alfalfa leafcutter bee, Megachile rotundata (F.), has become the dominant pollinator of alfalfa in Canada in recent decades. This has been critical to developing the alfalfa seed industry, since the honey bee is a quite inadequate pollinator of alfalfa in Canada. Not only is Canada now self-sufficient in alfalfa seed production, but it has become the world's chief exporter of alfalfa leafcutter bees (Small et al. 1997). All Canadian alfalfa cultivars contain high amounts of hemolytic saponins, which have been demonstrated to be very detrimental to poultry, and somewhat detrimental to pigs, both classes of livestock whose exports are expected to increase dramatically in Canada. The recent discovery of Turkish strains that are essentially devoid of hemolytic saponins (Small 1996) has the potential of leading to greater usage of alfalfa in the livestock industry.

Cicer Milkvetch (Astragalus cicer L.)

Cicer milkvetch has been considered to be a legume with good grazing potential for the last two decades in Canada. A new cultivar, said to be high-yielding, bloat-free, long-lived, easy to grow, appealing to cattle, not appealing to pocket gophers, and lacking serious diseases or insect pests, is scheduled for release from AAFC at Lethbridge in 2000.

Crownvetch (Coronilla varia L.)

This winter-hardy, salt-tolerant forage is being developed in Canada. It is used principally in this country to protect steep roadsides against erosion, but has good forage possibilities.

Fenugreek (Trigonella foenum-graecum L.)

Fenugreek is best known as a popular Asian seed spice, but it has also been grown as a livestock feed in the Old World. Fenugreek for forage is a quite recent novelty in Canada, where it has proven to be an excellent legume silage, yielding as much dry matter as two cuts of alfalfa, and 16–18% protein (compared with 18–20% for alfalfa) (Small 1997a). although cattle show initial reluctance to consume the strong-smelling fenugreek, they adjust to it in 7–10 days. The advantage over alfalfa possessed by fenugreek is that is an annual, therefore useful in a rapid crop rotation, for example with barley grain for silage. Fenugreek contains compounds with oxytocin activity (hormones that induce milk letdown in humans and animals), and this property may be desirable for dairy cattle. Fenugreek is also a natural source of diosgenin, a precursor of steroids used in the manufacture of birth control pills and other drugs, and it may one day replace present commercial sources [South American yam (Dioscorea) species].

Lupins (Lupinus species, especially white lupin, L. albus L.)

Lupins have attracted some interest in eastern Canada as a frost-tolerant, high-protein, nitrogen-fixing livestock feed. In Western Canada, success has been much more limited. For a brief review of Canadian experience, see Henckes and Leake (1994).

VEGETABLES

Except for potato (discussed below), most of Canada's fresh vegetables are grown in Ontario and Quebec. The vegetable growing area in Canada has been expanding for many years (Fig. 9), and has increased 76% to 128,000 ha between 1951 and 1996. The crops with the most area devoted to cultivation were sweet corn, peas, tomato, carrot, and bean. However, the most lucrative crops on a per hectare basis were shallots ($16,709), lettuce ($16,071), and celery ($15,167)—about twice the per hectare value of tomatoes ($8,644) and much higher than sweet corn ($1,609) and peas ($1,228) (Statistics Canada 1998b).

Figure 9
Fig. 9. Area of potato and other vegetables in Canada, based on the comprehensive 10-yearly (1921–1951) and 5-yearly (1951–present) agricultural censuses.
Figure 10
Fig. 10. Farm gate values (for 1997) of the 23 leading vegetable crops in Canada.

The relative value of the 23 most important Canadian vegetable crops is shown in Fig. 10. This diversity makes it difficult for any new vegetable to capture much of the market. Nevertheless, in recent years Canadian farmers have been growing more non-traditional vegetables, such as daikon radishes, bok choy, and escarole, a reflection of Canada's changing ethnic mix and more cosmopolitan tastes in food. An extensive analysis of all Canadian vegetables, with information on new cultivars and new trends, is Munro and Small (1997).

The only Canadian native vegetable that has elicited significant interest for domestication is ostrich fern [Matteuccia struthiopteris (L.) Todaro]. Young fronds are harvested as "fiddleheads" in Nova Scotia and New Brunswick for the gourmet food market. This crop is gathered from natural stands, but there is some interest in commercial cultivation. Although fern breeding is complicated, abundant genetic variability appears to be present in Canada and could serve to improve an already very attractive and novel crop.

Potato (Solanum tuberosum L.)

The potato is unusual in that, aside from forages, it is the only crop grown commercially in every province of Canada. Potatoes are cultivated in large amounts in Canada most notably on Prince Edward Island, where most of the arable area of the province is devoted to this single crop. Since the market for potatoes is quite good, there has not been much interest in diversifying the agriculture base on PEI, where farmers are content with this most perfect of food plants. A larger area of Canada was devoted to potato in the 1920s than today, but the crop has been expanding in recent years in all of Canada (Fig. 9), especially in Manitoba and Prince Edward Island. The increases in potato area have been due to increased processing capacity, primarily for export markets. Because of the large volume of the crop, the potato has long been a candidate for new uses. The potato is especially susceptible to disease and insect problems, and is the most chemically intensive crop grown in Canada, so that dependence on it can be somewhat unsettling. Because of the narrow genetic base of the major cultivars, there is an international effort underway to utilize the over 200 tuber-bearing species of Solanum in order to make modern potato more resistant to diseases and insects. For more information on potato in Canada, see Munro and Small (1997).

Mushrooms

The white button mushroom [Agaricus bisporus ( Lange) Imbach] commonly sold in supermarkets is the predominant commercial mushroom. There are only a few hundred mushroom farms in Canada, but their gross sales (close to a million dollars/farm annually) are 10 times that of the average farm in Canada. However, a large investment in buildings is required, as well as a large number of workers. Ontario is the leading production area of fresh and processed mushrooms (over 50%), followed by British Columbia (about 30%) and the prairie provinces (about 15%). There are widespread attempts underway in Canada to establish mushroom farms in other areas. Mushrooms can be cultivated almost anywhere (although proximity to markets is important), and provide a good means of crop diversification. The mushroom industry is useful in using up Canada's large supply of manure.

Specialty mushrooms include enoki, maitake, nameko, oyster, pompom, shiitake, shimeji, wine cap, and others. These unusual mushroom species are valued by ethnic markets in North America, and by trendy restaurants, and therefore provide promise of a growing market in Canada.

Wild edible mushrooms, primarily pine mushrooms, chanterelles, morels, and false morels, have become an important and growing multimillion dollar industry in Canada (Redhead 1992). Although mushrooms are wildcrafted throughout Canada, most of the commercial wild supply is harvested in British Columbia. The pine mushroom [Tricholoma magnivelare (Peck) Redhead] is Canada's most important wild mushroom (Redhead 1997). It resembles the Japanese matsutake, which is esteemed in Japan, and over the last decade Canada has exported almost all of its harvest of pine mushrooms in fresh form to Japan. In Japan, the retail price of fresh pine mushrooms can exceed $200/pound, while Canadian pickers can receive up to $100/pound. In 1993 Canadian exports of pine mushrooms to Japan were worth 1,840,000,000 yen (Anonymous 1995; at the time, 1 American dollar was worth about 117 yen). There is also a large chanterelle harvest in Canada, in the West and in the Maritimes. Chanterelles and morels are generally exported to Europe.

CULINARY HERBS

Culinary herbs and spices have been gaining in favor in Canada, and there are now thousands of hectares grown annually. The species are too numerous to document here, and only a few examples will be given. Coriander (Coriandrum sativum L.) has proven to grown very well in Saskatchewan, where 3,765 ha were grown in 1996. Over 400 ha of garlic (Allium sativum L.) were grown in Canada in 1996, by about 480 farmers, a challenging endeavor because of the climate. Stevia [Stevia rebaudiana (Bertoni) Bertoni] is a new crop in Canada, grown mostly experimentally to date, in British Columbia, Alberta, and especially in Ontario (Borie 1998). This perennial herb of Paraguay and Brazil provides a non-nutritive sweetener that is widely used in Asia, although not yet judged acceptable for consumption in North America. It has been developed into an annual crop in Canada, but whether it will be able to compete with the perennial crop grown in California remains to be seen. Detailed information on the more than 100 culinary herbs that are grown in Canada is in Small (1997a).

GREENHOUSE CROPS

Figure 11
Fig. 11. Farm gate values (for 1996) of the 12 leading glasshouse ornamental crops in Canada.

The relatively short growing season of Canada, by comparison with more southern countries from which crops can be imported, is a handicap for agriculture. Not surprisingly, glasshouse culture provides an important partial solution. Greenhouse cultivation (including glass, plastic or other protection) is expanding rapidly in Canada. All provinces are experiencing an increase in greenhouse area, with the largest increase in Ontario, especially in the Leamington area. The total area of greenhouse culture in Canada doubled from 1981 to 1996 to 12.7 million square meters (about 1,300 ha). Between 1991 and 1996, the increase was 51%. In 1996, greenhouse growers achieved sales of about a billion dollars. The sale of cut flowers and potted plants represented three-quarters of this (the values of the major species are shown in Fig. 11), and there was also about $200 million in vegetable sales. Tomatoes represent half of Canadian greenhouse vegetables, and generate a gross income of over $500,000 per hectare. Half of the greenhouse tomato crop is grown in Ontario. The very high income, coupled with a large domestic market and a potentially large export market to the US may explain why tomato is such a popular greenhouse vegetable crop. The other major Canadian greenhouse crops—cucumber, lettuce, and pepper, are also very high value crops during the Canadian winter. Among greenhouse trends in Canada are: use of longer lasting covering materials as well as material that allow more light transmission; change to hydroponic/soilless culture (especially rockwool); computerization of controls for the greenhouse environment; and carbon dioxide supplementation. There has also been a significant switch from growing pink-colored tomato cultivars to red-colored. The latter are more acceptable in the US market, and the recent large greenhouse area increase in Ontario has been for exports to the US.

FRUITS

Figure 12
Fig. 12. Farm gate values (for 1997) of the 11 leading fruit crops in Canada.

The values of the 11 leading Canadian fruit crops are shown in Fig. 12 (see Small and Catling 1996 for a review that also includes minor fruits grown in Canada). The most commonly cultivated fruits in Canada are apple, blueberry, grape, strawberry, and raspberry. About a third of the fruit area of Canada is devoted to low bush blueberry production, largely from Quebec eastward. The remaining cultivated fruit area is widely distributed in Canada. As with vegetables (above), the crops with the most area devoted to cultivation do not produce the maximum gross return per hectare. The most lucrative per hectare crops are cranberry ($24,861), kiwi ($23,101), sweet cherry ($10,998), strawberry ($9,859), and peach ($9,138)—all higher than the leading fruits, apple ($5,127), blueberry ($3,284), and grape ($6,706) (Statistics Canada 1998b).

Breeding of new fruit cultivars has been fairly continuous in recent years in Canada. Breeding programs for tree fruits in Canada are discussed by Quamme (1996), and for the small fruits by Jamieson (1996). Numerous raspberry and strawberry cultivars have been released from AAFC at Vancouver, and kiwi (Actinidia deliciosa C.S. Liang & A.R. Fergusson) was recently developed as a Canadian crop, although high world production of this fruit has depressed its profitability. AAFC at Vancouver recently introduced into Canada the grape kiwi (also known as winter kiwi and arguta) [A. arguta (Siebold & Zucc.) Planch ex Miq.], which is hardy to –25°C and produces abundant clusters of smooth-skinned berries that are more flavorful than full-sized kiwis. There are several cultivars of this relatively new fruit, which is acquiring popularity in British Columbia and the northwestern US.

Cranberry (Vaccinium macrocarpon Ait.) is a minor fruit crop in Canada. The center of cranberry cultivation and production is Massachusetts, but large quantities are also raised in the peatlands of British Columbia, as well as New Jersey, Washington, and Oregon. Considerable cranberry culture also occurs in Wisconsin, and in limited degree in Ontario, Quebec, and the maritime provinces (especially New Brunswick and Nova Scotia). Cranberry is receiving increasing attention in Quebec. Cranberry is rather unique among crops in that it has been grown for many years but still demand exceeds supply. About 10% of Canada is covered by peatlands, and there is no shortage of peat with which to construct engineered (i.e. artificially constructed) bogs to grow this crop. There has been concern that environmentally sensitive wetlands might be eliminated or damaged by development of new cranberry bogs, but technology is available to control damage to wetland sites, and even to develop bogs on dryland sites. Canada has the resources to expand its cranberry industry, and this could become the most important new fruit crop in certain areas.

There is a small grape wine industry in British Columbia and southern Ontario, and a very small industry in Quebec and Nova Scotia. Most people are surprised to learn that despite the cold climate of Canada, prize-winning wines are occasionally produced that rival the best wines of the world. Less surprising is the fact that a Canadian specialty is ice-wine, made from grapes allowed to freeze on the vine. Labrusca-type grape plantations (with germplasm of the North American fox grape, Vitis labrusca L.) are being replaced in Canada with vinifera grapes (imported cultivars of the European V. vinifera L.) for wine-making. Until the 1980s, Canadian wines were made mainly from native labrusca cultivars, such as 'Concord' and 'Niagara'; these grapes are grown today mainly for juices, jams, and the fresh markets. Vinifera grape cultivars, such as 'Cabernet Sauvignon', are cultivated for wine-making. Hybrids of the two types, for example 'Vidal', are grown in Ontario to make ice wine. For a review of the grape wine industry in Canada, see Read (1994).

There are over 100 wild fruit species gathered in Canada (Turner and Szczawinski 1979). These are well adapted to the climate and soils, and would seem to offer excellent prospects for domestication. In fact, only two wild fruits have received much breeding attention in Canada as new fruits (sandcherries, Prunus spp., have been bred as ornamentals). Saskatoon (Amelanchier alnifolia Nutt.) is perhaps the best example of domestication of a Canadian indigenous species (see Mazza and Davidson 1993 for a good review). Considerably improved forms were bred by AAFC at Beaverlodge, Alberta, and the annual farm gate value exceeds a million dollars. Although this crop is still in its infancy, it has been predicted that over 4000 ha of saskatoons could eventually be planted on the prairies (Henckes and Dietz 1992). Although still basically a wild crop, lowbush blueberry (Vaccinium angustifolium Ait.) has undergone considerable selection at AAFC, Kentville, Nova Scotia. About 9,000 kg of wild lowbush blueberries are harvested annually in Canada, largely from stands that are managed by burning, fertilizing, or pruning. Other possibilities of wild Canadian fruits that deserve consideration for domestication are: lingonberry (Vaccinium vitis-idaea L.), with harvests in Newfoundland of the order of 150,000 kg annually (domesticated cultivars from Europe are cultivated to a small extent in Canada); highbush cranberry (Viburnum trilobum Marsh.); cherries (Prunus "> Fig. 13. Area of tree fruits in Canada, based on the comprehensive 10-yearly (1921–1951) and 5-yearly (1951–present) agricultural censuses.

Tree fruit area has been decreasing very steadily and noticeably for the past 75 years in Canada (Fig. 13), and an explanation is in order. Trees and to a lesser extent bush fruits are a long-term investment that cannot respond flexibly to market fluctuations, i.e. one can't put in another crop easily if market or weather conditions suggest this would be advantageous. However, these are universal problems with woody perennials; below, some special problems in growing such plants in Canada are discussed.

There are ecological reason why most fruits (and also nuts) are competitively disadvantaged in Canada. Most commercial fruits (strawberry is an exception) and nuts (peanuts is an exception) are woody perennials. Woody perennials put a substantial portion of their energy into building up wood and, in deciduous plants, regrowing their foliage annually. In a long-season climate, both the woody tissues and leaf tissues are functionally useful for a long period. By contrast, in short-season climates as found in Canada, growing wood and new leaves annually, and indeed consolidating energy reserves to survive the winter, represent a proportionately greater deflection of energy from fruit production. Still another reason has to do with the greater intensity of insolation in areas near the equator. Moreover, trees near the equator can intercept as much as 95% of the annual incident radiation, while annuals may intercept as little as 20% (Corley 1989). Still another factor favoring woody fruit trees in tropical regions is that the soil is often too infertile to support unfertilized annual crops, so that growing woody plants is highly advantageous. For these reasons, perennial crops are far less common in northern climates such as Canada's in comparison with tropical and subtropical areas.

NUTS

Filberts (Corylus spp., also known as hazel nuts), grown in British Columbia, are the only significant nut crop in Canada. A small crop of peanut (Arachis hypogaea L.) has been grown for some time in southern Ontario, for the peanut butter crop. Attempts to grown peanut in southern Alberta were unsuccessful because the growing season proved too short. The walnut (Juglans nigra L.) and butternut (J. cinerea L.) can be grown in Canada, but not competitively (a very limited amount of walnuts have been grown in British Columbia). Cold-hardy forms of the English walnut (J. regia L.), particularly the Carpathian walnut, can also be grown in the warmest regions of Canada. At least one grower in Ontario is marketing the Japanese heartnut [J. ailantifolia Carri¸re var. cordiformis (Maxim.) Rehd., known also under other names]. Numerous popular nuts can be grown efficiently in warm-temperate and hot regions, and because of their very good keeping qualities and the economy of transportation of these high-value, relatively light commodities, a strong nut industry has not developed in Canada, and indeed does not have good prospects.

AROMATIC CROPS

Interest in Canada in essential oil crops is centered in Western Canada. Crops that can be grown there include: dill (Anethum graveolens L.), caraway (Carum carvi L.), coriander, spearmint (Mentha spicata L.; also Scotch spearmint, M. ×gracilis Sole), peppermint (Mentha ×piperita L.), hyssop (Hyssopus officinalis L.), horseradish (Armoracia rusticana P. Gaertn., B. Mey. & Scherb.), garlic, onion (Allium cepa L.), monarda (Monarda species and hybrids), fennel (Foeniculum vulgare Mill.), fenugreek, summer savory (Satureja hortensis L.), sage (Salvia officinalis L.), tarragon (Artemisia dracunculus L.), chives (Allium schoenoprasum L.), anise-hyssop [Agastache foeniculum (Pursh) O. Kuntze], parsley [Petroselinum crispum (Mill.) Nym ex A.W. Hill], and basil (Ocimum basilicum L.). The essential oil industry is in its infancy in Canada (several thousand hectares and several million dollars in total), so the long-term success of most of these species as aromatic sources in Canada still remains to be determined. The majority of these can also be grown as fresh or dried flavoring herbs/spices, and coriander grown as a spice has had reasonable success. However, the market for aromatic and spice crops is very competitive, with considerable, efficient foreign production, so that just how much growth potential there is in Canada remains an issue.

A review of new essential oil crops in Canada concluded that monarda (Monarda punctata L., and hybrids) was the most promising possibility (Ference 1989). Several lines of monarda, each line yielding a distinctive fragrance, were bred at AAFC, Morden, Manitoba (Anon. 1992; Mazza et al. 1993). A similar attempt was made to develop several lines of anise-hyssop (Anon. 1992). Considerable investment in research went into these projects, and although useful cultivars resulted, in retrospect it is unclear whether the efforts were worthwhile economically. For additional information on essential oil crops in Canada, see Small (1997a).

MEDICINAL CROPS

This category of crops overlaps with nutraceuticals. Therapeutic crops primarily marketed as herbal preparations or for medicinal extracts can be considered to be medicinal crops, while those serving as sources for extraction or preparation of nutritional substances can be segregated as nutraceutical crops. There is a limited amount of wildcrafting of medicinal plants in Canada, and cultivation is now predominant. A wide variety of medicinal crops are grown in Canada, but none is very important except ginseng. However, there is considerable enthusiasm for the cultivation of medicinal herbs, and the industry is expanding in Canada. Small and Catling (in press) presents a detailed analysis of medicinal crops in Canada, as well as a guide to Canadian experts who specialize in medicinal crop development.

Ginseng (i.e. "American ginseng," Panax quinquefolius L.) has continued to dominate the cultivation of medicinal plants in Canada, with two-thirds grown in Ontario, and most of the remainder in British Columbia. The industry in British Columbia is only two decades old, and demonstrates very well how a lucrative crop can be successfully transplanted to another region. Wild collection of ginseng is no longer authorized in Canada, and ginseng populations have been greatly reduced in this century. Most of the crop is exported to Asia, and in 1996 over 1 million kg of ginseng roots were exported. Ginseng grows well on well-drained, sandy-loam soil, much like that for tobacco, and so most of Canada's ginseng is grown in the traditional tobacco area of southwestern Ontario. There is some interest in reviving woodland cultivation of ginseng. A very limited amount of Asian ginseng (P. ginseng C.A. Mey.) is raised in Canada, and there is very strong opposition to this from the ginseng industry, which fears the possible introduction of diseases or other unknown problems.

NUTRACEUTICAL CROPS

"Nutraceuticals" may be any of a wide variety of consumable products, such as foods, pills, powders, and indeed the definition of nutraceuticals varies geographically. In Europe, nutraceuticals are generally restricted to natural ingredients, because of strong consumer interest in natural herbal medicines. In the US, nutraceuticals are not necessarily of natural origin. In Canada, nutraceuticals, "functional foods," and "pharmafoods" are terms frequently used to describe food or products that have physiological benefits or reduce the incidence of chronic disease. Foods recommended by a physician to manage a disease or health condition such as obesity, gluten intolerance, or diabetes are often excluded from the definition of nutraceutical, although this is arbitrary. Various extracted constituents from food crops provide important nutraceuticals. The extracted fiber of oatmeal, wheat bran, barley, lentil, peas, and beans provides health benefits. The insoluble fiber in wheat bran, lentil, and brown rice reduces potential carcinogens in the colon. The soluble fiber in oat bran, dried common bean, and barley fights heart disease by reducing the absorption of cholesterol. Flaxseed can reduce cancer and heart disease, its omega-3 fatty acids decreases blood cholesterol, and its phytoestrogens or lignans are thought to reduce the incidence of breast cancer. Canola oil is healthy because of its relatively low level of saturated fatty acids, but it also contains significant amounts of essential fatty acids, such as oleic acid, which lowers plasma cholesterol levels, and linoleic and linolenic acids, which convert to hormone-like substances (eicosanoids) that affect physiological reactions ranging from blood clotting to immune response. Soybean contain isoflavones, which help reduce the negative effects of estrogen on the human body, ease some symptoms of menopause, reduce hypertension and heart disease, and may be related to a lowered rate of breast and prostate cancer. Chicory (Cichorium intybus L.) was recently examined as a source of inulin, which has nutraceutical and feed applications (Lachance 1996). Inulin can also be produced from Jerusalem artichoke (Helianthus tuberosus L.).

Nutraceuticals are exploding in importance in the natural health and food products industry, and represent a multi-billion dollar market. The US market has been estimated to be about $1.5 billion, and the Canadian market about $150 million. The growth of nutraceuticals is due to an increasing tendency to fortify foods with disease preventing qualities. This trend is related to an aging population, increasing health care costs, consumer interest in nutrition, and food technology advances. The growing market provides an excellent opportunity for the Canadian agri-food sector to diversify. It is especially significant financially because the products that can be produced have high value added (Spak 1998a).

The chief roadblock at present to the development of both the nutraceutical and medicinal herbal industry in Canada is regulatory uncertainty with respect to the marketing of these products. In Canada, as in many countries, these often fall into a grey and ambiguous area between food and drug. Canada currently does not allow claims of specific health benefits for herbal remedies and nutritional supplements, unless they are elevated to the category of drug, in which case efficacy must be proven by clinical trials. All crops potentially can yield nutraceuticals, but crops that are produced in very large amounts are especially significant. Most of the 60 million tonnes of grains, oilseeds, and special crops produced annually in Canada have the potential to be processed into nutraceuticals for domestic and global markets. This area is attracting a great deal of scientific research and market development in Canada, and is likely to be an important factor in the future regarding the cultivation of new crops in various regions.

Gamma linolenic acid (GLA) is used medicinally, particularly for treating atopic eczema, a common skin rash, and for nutritional deficiencies. It is obtainable from the seeds of many plants, although to date two species have been the chief sources. Borage (Borago officinalis L.) is an ancient, essentially undomesticated species, native to the Mediterranean, that has been considered as a diversification crop in many countries, both as a forage and as a medicinal plant. Considerable amounts have been grown in Saskatchewan. Most borage oil is produced in Europe and Asia, but since the crop seems well adapted to the cool growing conditions in parts of the prairies, and possibly also to eastern Canada, it has potential for further development in Canada. The chief drawback of borage is that most available cultivars produce seeds over a long period, shattering them gradually, so that only about 20% of the seed crop can be collected by conventional means (in Europe, some relatively non-shattering cultivars have been bred). Evening primrose (Oenothera biennis L.) seed oil also contains high levels of GLA, and is occasionally grown as a substitute crop for tobacco in southern Ontario. Ference (1989) concluded that evening primrose is a better diversification crop for Canada than borage. Foreign competition, market volatility and lack of processing facilities limit both crops in Canada. The possible use of hemp for GLA production is discussed below. For further information on these species as new Canadian crops, see Small (1997a) and Small and Catling (in press).

Sea buckthorn (Hippophae rhamnoides L.) is a shrub that is widely planted on the Canadian prairies as a nitrogen-fixing, soil-conserving, hardy shelterbelt. The berries are used to a small extent to make jams and jellies, but this usage is very limited. However, a venture is underway to process sea buckthorn berries and leaves into a range of health foods and herbal products (Henckes 1998b), with the goal of harvesting sea buckthorn orchards from British Columbia to Manitoba. The fruit is high in vitamins C and E and beta carotene, as well as flavonoids, and the oil is high in essential fatty acids. Essential oils from the fruit can be used in nutritional supplements, skin creams, and other products. In Eurasia the oil has a reputation for relieving pain, reducing inflammation, and fighting bacterial infections. This potential new crop requires a great deal of development, but has succeeded in stimulating considerable interest in Canada.

TEXTILE FIBER CROPS

There is an absence of successful textile fiber plants in Canada, and accordingly there is interest in finding new fiber plants. Oilseed flax is discussed above as a very promising new crop for Canada. In the US flax is extensively employed in papermaking, especially using decorticated straw ("flax tow") from oilseed cultivars grown for linseed oil and meal, obtained from both the US and Canada. Although fiber flax is adapted to Canada's cool-temperate climates, international competition seems to have suppressed the textile crop industry in Canada. Fiber flax cultivars have been grown in Canada, but have only acquired a fraction of the success of oilseed cultivars. As noted below, fiber hemp is likely to be used for fiber production in Canada, but the clothing use will likely remain limited. A shortage of imported fiber during the second world war led to exploration of fluff from common milkweed species (Asclepias syriaca L. and A. speciosa Torr.) as a substitute. This proved unsuccessful, but with the success of this crop in the US (Witt and Nelson 1992), a further Canadian exploration of the potential for textile, paper, fiberfill, and insulation was initiated by AAFC at Saint-Jean-sur-Richelieu. This has not led to the establishment of a new fiber industry in Canada.

Hemp (Cannabis sativa L.) grown under license for fiber as well as oilseed products is the most publicized new crop in Canada, and there are currently thousands of hectares under cultivation by hundreds of authorized farmers. Hemp is being grown both for traditional textile, paper, cordage, and oilseed usages, but also for a variety of new uses (composite building and manufacturing materials; nutritional, cosmetic, and industrial preparations; biomass applications). As detailed information on Canadian hemp is given by Moes (this symposium), and in several publications cited below, the presentation here is limited. Until very recently the prohibition against drug forms of the plant prevented consideration of cultivation of fiber and oilseed forms in Canada. However, in the last 5 years three key developments occurred: (1) much-publicized recent advances in the legal cultivation of hemp in western Europe, especially for new value-added products; (2) enterprising farmers and farm groups became convinced of the agricultural potential of hemp in Canada, and obtained permits to conduct experimental cultivation; and (3) lobby groups convinced the Parliament of Canada that narcotic forms of the hemp plant are distinct and distinguishable from fiber and oilseed forms. There are indeed two categories of plants, formally recognized as subspecies by Small and Cronquist (1976): C. sativa subsp. sativa, comprising fiber and oilseed forms, as well as similar wild plants; and C. sativa subsp. indica (Lam.) E. Small & Cronq., comprising drug forms of the plant, as well as similar wild plants. These two subspecies were defined on the basis of their intoxicant potential: subsp. sativa with less than 0.3% tetrahydrocannabinol (THC) in the foliage and flowering parts (dry weight basis); and subsp. indica with more than 0.3%. This level of 0.3% THC is now used in the European Economic Community and Canada as a criterion for authorization of cultivation. Cultivars with less than 0.3% may be legally cultivated under license, whereas those with levels of 0.3% or greater may not. There are considerable efforts underway in the US to convince the authorities that hemp cultivation should be carried out similarly as in Europe and Canada, but concern over the narcotic types of plant remains the key obstacle, as it did for many years in Europe and Canada. Objective evaluation of hemp as a crop is complicated because of the emotion connected with the drug use of the species. Exaggerated claims of hemp's values are common, and have contributed to the growing bandwagon of authorized cultivation in Canada. The next few years will determine the extent to which hemp can be grown as a new economic crop in Canada, and could influence its future possibilities in the US, where historically it was grown very successfully for a very long period, in much greater quantities than ever occurred in Canada. For further information on hemp in Canada, see Reichert (1994), Small (1979, 1995a,b, 1997b) and Montford and Small (1999).

PULP, BIOMASS, AND ENERGY CROPS

These categories are discussed together because the crops used often serve the three purposes.

Pulp

Kenaf (Hibiscus cannabinus L.), a native of east-central Africa, was recently considered to be a candidate for diversification in Ontario, as a newsprint source, although it is much better adapted to the southern US, where it is now grown and has received much favorable publicity. Experimental growth in southern Ontario succeeded only in showing that the crop cannot be grown competitively here. As noted below, poplar and willow lines are available as agroforestry crops in Canada for pulp, and because they can occupy vast areas of marginal Canadian land, they are a much more likely source of pulp than herbaceous crops that require prime agricultural land. However, 40% of Canada is forested, and this vast supply of wood and wood products limits the prospects for all new pulp sources.

Straw-Based Particleboard

As much as 40 million tonnes of cereal straw are produced annually in Canada as a by-product of growing grain. Traditionally, these crop residues have been incorporated back into the soil, used as bedding or a feed additive for livestock or, least desirably, burned on the field, producing air pollution. Rarely, the straw has been used for pulp for paper, ethanol, space heating, and building materials. Very recently, high-grade particleboard (made with the resin methyl-diphenyl-isocyanate, better known as "crazy glue"), using mostly wheat straw, has come into commercial production on the Canadian Prairies. At least here, this venture seems economical. Plywood and oriented strandboard (long strips of wood oriented and blended with adhesives) can be produced relatively cheaply in heavily wooded areas such as the Pacific Northwest, the US Northeast, Quebec, and New Brunswick. Waferboard (wood flakes glued together under pressure) can be cheaply produced from aspen, which is very abundant in Canada, including much of the Northern Prairies, and the long-term success of cereal straw board remains to be demonstrated. Also, fiberboard (produced by fiberizing wood particles as in a semi-pulping process to create a dense board that holds screws better than particleboard) is an economical way of using up the rather large amounts of waste material from the lumber industry. As noted above, hemp is also is under investigation as a new type of biofiber/resin board in Canada. Reichert (1995, 1996) reviews the potential of straw-based particleboard in Canada.

Biodiesel

Biodiesel fuels are derived from renewable biological resources for use in diesel engines. Biodiesel is more viscous than conventional diesel, and therefore less useful at lower temperatures, limiting its use in Canada. Nevertheless, in Canada and similar cold areas, biodiesel can be marketed as an additive in a 5–10% blend with conventional diesel fuel. Canadian biodiesel technology has refined the hydro-treating method using a conventional refining process like that used in the petroleum industry. This produces cetane, a booster for diesel fuel, as well as naphtha and other products. Oilseed crops such as soybean, canola, and sunflower are particularly useful for producing biodiesel fuel (which can also be obtained from other vegetable oils, such as maize and peanut oil, and animal fats). Biodiesel is primarily useful as a means of improving air quality, particularly for lowering sulphur emissions from fossil fuels. Other benefits include decreasing energy dependence on foreign imports, reduction of greenhouse gases, lower toxicity resulting from accidental spills, improved biodegradation, and the creation of employment (as biodiesel production is several times more labor intensive per unit of production than fossil fuels). Another result is the production of high-quality glycerine (used in such products as hand creams, toothpaste, and lubricants) as a by-product (when the transesterification process is used), but this has created a glut of glycerine on the market. The cost of biodiesel production may be two to three times that of petroleum fuels, and biodiesel seems justified only in areas where air pollution is a significant problem. Europe has been the primary area of support of the use of biodiesel, and the European Community has committed large sums of money to this. When one considers the negative environmental impacts of increased fertilizer and pesticide use in using oilseeds to manufacture biodiesel, it is less clear that biodiesel is desirable environmentally. In Canada, biodiesel production seems like a reasonable alternative for using up surplus and frost-damaged oilseeds. Moreover, with increasing industrialization, pollution is likely to increase in large Canadian cities, making subsidization of production more attractive. For an analysis of the biodiesel situation in Canada, see Gowan (1996).

Ethanol

Alcohol can be used as a fuel for vehicle engines, a fuel extender when blended with gasoline, and as an octane enhancer. The two most important alcohols for fuel use are ethanol and methanol. The latter is produced from natural gas, coal and wood, all in high supply in Canada. Alcohol-blended fuels (gasohol) are widely considered desirable for their environmental benefits, reducing polluting vehicle emissions and contributing to the effort to stabilize and reduce emissions of greenhouse gases related to global warming. Crops such as maize, potato, sorghum, and sugarbeet, which produce considerable biomass and a large carbohydrate yield, have the potential for production of alcohol. In North America, about 95% of fuel ethanol is manufactured from maize. Small amounts are made from wheat and barley, and can potentially be obtained from cull potato, Jerusalem artichoke, other cereal crops, lignocellulosic material such as maize hulls, switchgrass (Panicum virgatum L.), wood waste, and municipal solid waste (McKeague 1994). Ethanol production also offer opportunities to the grains and oilseeds industries. An integrated ethanol plant that consumes grains or oilseeds can produce edible livestock products in addition to alcohol. Like biodiesel fuel discussed above, current production costs relative to current petroleum is prohibitive, unless there is subsidization. The US has provided considerable subsidization to the production of fuel alcohol from maize. Canada does not have the highly polluted areas which occur in the US, so that there is less incentive to enact environmentally-oriented legislation supporting fuel alcohol production. Maize is a more prominent crop in the US, and maize technology is more advanced. Nevertheless ethanol-enhanced fuels have gained some popularity in Canada, and there is a reasonable prospect that a variety of new and old crops can be adapted with new technology to a more substantial bioethanol industry in Canada. In particular, maize for the production of ethanol is considered to have excellent potential in Canada (McKinnon 1997c), a part of the trend toward use of renewable raw material for industrial processes rather than non-renewable petroleum. Several industrial plants use maize in Western Canada, and new ethanol production plants have been established in Ontario and Quebec. Jerusalem artichoke (Helianthus tuberosus L.) has undergone selection in Canada as a new diversification crop (Hergert 1991), but it was found that it could not be grown profitably in Canada as an alcohol source (Baker et al. 1990).

Canadian scientists have developed hybrid poplars (Populus spp.) and willows (Salix spp.) as biomass crops for ethanol, pulp and the generation of electricity and heat (Mitchell et al. 1992; Abuja and Libby 1993). The trees thrive on marginal soils and cool climates, annually yielding up to 3.7 tonnes of biomass per hectare. It has been estimated that if willows were grown on 10% of Canada's marginal farmland, the fuel could replace ten nuclear generating plants and supply much of Canada's gasoline (Gogerty 1991). The use of trees for fuels, although less efficient than crops, may be a more reasonable alternative for Canada, since the trees can occupy the huge areas of marginal land unsuitable for crops. Switchgrass has acquired a considerable reputation as a potential biomass, ethanol and pulp plant in the US, and has been considered like willows and poplars for energy and fuel alternatives in Canada. All prospective energy crops in Canada must compete with relatively inexpensive supplies of natural gas, hydroelectric power, and wood, so that traditional fuel sources are unlikely to be replaced in the foreseeable future.

LANDSCAPE PLANTS AND CHRISTMAS TREES

The landscape industry in Canada is very large and diverse. However, national statistics are compiled only for sod, which in 1996 had a farm gate value of about 66 million dollars. AAFC at Morden, Manitoba, has been especially active in Canada in developing the landscape industry, generating new and improved winterhardy roses (e.g. 'Morden Blush' and 'Morden Fireglow'), herbaceous perennials, trees, and shrubs. Recent contributions from Morden include two new lilies for the Prairies, a fast-growing disease-resistant male poplar suitable for shelters, a new winter-hardy hedge rose ('Prairie Joy'), and a new fall-bearing raspberry ('Red River'). 'Nicolas' and 'Lambert Closse', new roses in the Explorer series, were recently released by AAFC at Saint-Jean-sur-Richelieu, Quebec.

Christmas trees have become a growth industry in Canada, and according to the 1996 Census there were 51,071 ha cultivated. There are more than 2,000 Christmas tree farms, about a third in Quebec. In 1995, the last year for which data are available, 3.2 million Christmas trees were harvested in Canada, and 2.1 million of these were exported to the US. Traditionally popular species include Scotch pine (Pinus sylvestris L.), white pine (Pinus strobus L.), and white spruce [Picea glauca (Moench) Voss], but there is regional specialization. In British Columbia, Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] and Scotch pine are the leaders in Christmas tree sales. By contrast, Fraser and balsam firs [respectively Abies fraseri (Pursh) Poir. and A. balsamea (L.) Mill.] are the trees of choice in the maritime provinces, where they are easy to grow. Because preferences for the different species change (firs are becoming more popular) and it requires about a decade to grow a Christmas tree (in Canada, a fir requires 9 to 15 years to reach marketable height, while a Scots pine takes 8 to 10 years), consumer trends need to be predicted a decade in advance.

AQUACULTURE

Aquaculture* is one of the fastest growing food production industries in the world. Most aquacultural production occurs in Asia, but the industry is expanding everywhere, including North America. Below, the two principal categories are reviewed.

The Fishery

Animals that can be grown for food in water include finfish, molluscs (notably clams and oysters) and crustaceans. Because these are cold-blooded and do not use energy to produce heat, a very efficient conversion of feed to flesh can be realized (as low as 1.3 has been achieved for fish in the US). Canada has recently experienced catastrophic reductions in the East Coast fishery from overfishing, and the West Coast salmon fishery is experiencing widespread threats to its supply. Increased harvest of the oceans by fishing fleets from around the world has depleted ocean going fish stocks. Pollution and climate change have also been accused of playing a role in reducing the ocean's resources. The protein requirement of about 5% of the world's population is satisfied by fish and other seafood products, and this tradition of eating fish provides a stable market, especially in Japan. In developed western countries such as the US, Canada, and the European Community, it has become common knowledge that fish provide extremely beneficial dietary components, and have been linked in various studies to the reduction of disease. The market for fish is becoming more expensive to satisfy, and the culture of seafoods to meet this need is becoming more widespread. Culture of fish stocks also provides a way of restocking the sport fish industry, and even of providing captive fish for sport. High-gluten wheats such as are commonly produced in Western Canada are particularly well suited to capture a portion of the shrimp feed market, both as feed ingredients and binding agents, and soybean and canola meal also have potential for use in shrimp rations (McKeague 1993). Trout and salmon also provide a possible new outlet for products from grains and oilseeds, both for a new domestic aquaculture industry and for the export market. For a review of aquacultural potential of Canadian feeds, see Kurbis (1996a).

Seaweeds

The larger marine algae or seaweeds have a diversity of uses, like many terrestrial plants. Various seaweeds are used as vegetables and condiments, principally in China and Japan. Many brown algae have been extensively used as agricultural fertilizers, especially as a source of potash (which supplies potassium). As a soil amendment, seaweeds also tend to be rich in micronutrients and nitrogen, but are low in phosphate. They have the advantage of being free of terrestrial weeds and fungi. Algin from kelp and other algae is used in the manufacture of more than 300 commercial products, and is particularly valued for its ability to suspend agents in food, cosmetics, and a variety of commercial liquid mixtures. Like other seaweeds, kelp are also harvested as dried fodder for terrestrial livestock in coastal areas, and sometimes grown as forage for cultivated aquatic animals, such as abalone. A special roe on kelp, greatly valued in sushi bars of Japan, has been produced in British Columbia by herring spawning in penned kelp enclosures. The industry is largely managed by native people and the harvest is valued at over 20 million dollars annually. A recent development is the use of kelp as a substrate for biogas (methane) production, a technology that was developed during the OPEC crisis by General Electric of the United States. The value of this technology in reducing the high energy costs in the Canadian Arctic is currently being explored by Canadian companies.

Uncontrolled harvesting has led to reductions of wild supplies of some algae, but seaweed farms are well established in parts of the world, reducing the pressure on natural stands. "Polyculture" (combining fish farming and seaweed culture) is a clever way of using seaweeds to metabolize by-products of the fish culture. China is a major seaweed producer, growing over 2.5 million tonnes of the brown alga Laminaria japonica Aresch annually. Japan's primary aquaculture seaweed is nori (mostly the red alga Porphyra yezoensis Ueda), with an estimated value of $1.5 billion annually (by contrast, the edible seaweed market in the US is currently valued at only about $30 million annually). Canada's development of a cultivated seaweed industry lags far behind that of several countries with low labor costs and a warm climate that allows year-round cultivation. However, there has been some cultivation of Laminaria saccharina (L.) Lamouroux and L. groenlandica Rosenvinge (L. bongardiana Postels et Ruprecht) on the Pacific coast, for Oriental and health food markets.

Although Canada currently provides less than 2% of the world's seaweed resources, there is considerable potential for increasing commerce, particularly on the species-rich Pacific coast. In fact, with 20 kelp species, coastal British Columbia is one of the world's major regions of kelp diversity, and it has been estimated that 650,000 tonnes of wild kelp currently grow along the B.C. coastline. Current Canadian regulations permit 100,000 tonnes to be harvested annually under strict conservation guidelines, but less than 1% of this amount was harvested in 1996. Canada has the longest coastline of any nation, suggesting that greater use should be made of the cold-water marine plant resources. Canada's marine environment may remain much less polluted than elsewhere, providing an attractive situation for algae and algal products intended for human consumption. For additional information on the economics of seaweeds in Canada, see Small and Catling (in press).

ORGANIC AGRICULTURE

Organic farming employs agronomic practices minimizing or eliminating highly processed chemical inputs, stressing soil building programs, and long term environmental sustainability. Methods include the use of crop rotations, natural insect predators, and organic nutrient sources, as opposed to the use of pesticides, fungicides, insecticides, and chemical fertilizers. In Canada, there are at least 50 different organic certification agencies. Organic grains and oilseeds grown in Canada include wheat (including durum), oats, barley, rye, buckwheat, flax, canola, and sunflower. The majority of Canadian organic grains and oilseeds are exported (as are conventionally produced corresponding crops). The organic grains go primarily to Europe and the US, and the majority of organically-grown oilseeds to the US. Estimating the size of the organic grains and oilseed industry is difficult, but likely it is less than 1% of the conventional crops. Organic crops command higher prices, typically 30% for grains and oilseeds, but the extent to which production can be made competitive with conventional cropping is unclear (Christie 1995b). The organic industry is expected to increase the share of the food retail market in Canada as consumers become increasingly conscious of the issues.

Wise manure usage is related to the subject of organic agriculture. Canada has a huge livestock industry (over 100 million hens and chickens; 111 million hogs; almost 5 million beef cows and over 1 million dairy cows; more than one-quarter of the nation's farms are beef farms), and consequently an associated production of manure. Manure is a valuable resource due to its nutrient content and soil amending properties. On the other hand, manure is expensive to transport, produces an odor that the public finds objectionable, and over-application may pollute surface and ground water. New crops and crop systems that utilize all this manure are extremely desirable, and are a priority in Canada.

TRANSGENIC CROPS

New genetically engineered crops are becoming common in Canada, as in the US and elsewhere. Transgenic crops pose the following risks: (1) escape of the transgenic plants and proliferation in the wild with subsequent displacement of natural vegetation; (2) hybridization with and transgene infiltration into related weedy species, resulting in invigorated weeds; (3) hybridization with and transgene infiltration into native wild species, resulting in alteration of natural gene frequencies; and (4) damage to habitats and ecosystems, resulting from any or all of the above possibilities. Because of the cold winters, the relatively depauperate flora of Canada, and the relatively narrow spectrum of crops grown, transgenic crops pose less of a risk to Canada than they do to more southern countries. However, crops engineered for cold-tolerance pose a special risk for Canada, since temperature is the chief limiting factor for Canadian crops, and indeed for invasive weeds. Increased cold tolerance is a key factor in increasing the area of Canadian crops. Accordingly, genetically transformed plants that have been altered to increase cold tolerance must be given special scrutiny to ensure that escaping genes or plants will not influence native biodiversity. Cold stress tolerance could be expressed in several ways, for example: increased physiological tolerance, adaptation to early or late frosts, adaptation to a short growing season, conversion of a perennial incapable of winter survival to an annual that overwinters as seed, development of compact forms that self-insulate, and development of deep-growing overwintering roots or rhizomes. The risks of genetically engineered crops in Canada are reviewed by Small (1997c) and Warwick and Small (In press).

SUMMARY ANALYSIS

The principal north-temperate grains (wheat, barley, oats, and maize) have long dominated the crops of Canada. New cultivars are regularly created to meet the challenges of the Canadian climate, diseases, pests, and the international marketplace. Some new grains and pseudograins have been added, most notably canary seed, but remain minor. By contrast, in recent decades the oilseed sector has witnessed huge increases in the cultivation of canola (rapeseed), and soybean, and the introduction of new types of flaxseed, as well as several other species grown in minor amounts. The success of these new crops has been due to intensive Canadian breeding programs. Canadian forages and fodders are dominated by the major legume and grass species imported from temperate Eurasia, although some new Eurasian species have recently been added to the mix. An extensive effort is currently underway to develop native Canadian grass species as new forages and landscape restoration plants. The areas devoted to dry peas and beans have been increasing rapidly in the Canadian prairies, a planned successful response to recent decreases in wheat area. Vegetable production has been increasing in Canada for many years. A considerable variety of vegetable and culinary herb crops is grown in Canada, making it difficult for any new crop to gain much of a market share. Nevertheless, in response to growing ethnic diversity and appreciation for the importance of vegetables to health, many new species and new cultivars are appearing in Canada. By contrast, fruit crops have generally been decreasing in Canada, although new cultivars have appeared. There are numerous possibilities for domesticating native Canadian fruits and vegetables as new food plants, but the marketplace appears to be hostile to these prospects. Greenhouse cultivation is increasing very rapidly in Canada, with emphasis on ornamentals and a few vegetables, most notably tomato. The landscape and mushroom industries are also thriving. The greenhouse, landscape, and mushroom sectors are offering a wide diversity of new crops, although individual species are not likely to capture a large proportion of the markets. New medicinal and nutraceutical crops are attracting considerable attention and research in Canada, and while the farm gate values are limited, value-added processing makes this economic sector very promising. Textile fiber crops are basically absent from Canada, and the prospects for finding new crops for this category appear poor. The legal cultivation of hemp for a variety of purposes, particularly as an oilseed and high-quality pulp fiber source, is undergoing explosive growth in Canada, but the eventual success of this new crop remains to be determined. Herbaceous crops for biomass, energy, fuels, ethanol, and biodiesel have attracted attention in Canada, as in other countries. Subsidization is necessary for these, and is provided in Canada only for a limited amount of fuel ethanol production. Cheap hydroelectric power and abundant natural gas, as well as a huge wild supply of trees, strongly restrict the prospect of these industries in Canada. Among the challenges for the future are the following: utilizing the huge promise of new genetically-engineered crops without harming the environment and the native biota; finding crops and systems to utilize the large amount of manure from the livestock industry; and wisely developing the potentially large coastal seaweed industry.

REFERENCES


*Aquaculture is the controlled cultivation and harvest of aquatic animals and plants (mariculture is the raising of such crops in the sea). Aquiculture is often considered to be a variant spelling, but is also used in a narrower sense for hydroponics, the cultivation of plants in artificial aqueous nutrient media.
back