Rare Grassland Plants

Restricted to a few sites in highly developed areas, these grassland species are all at risk in British Columbia.

Ministry of Environment, Lands and Parks States, these species are extremely rare to Montana and Utah. In Canada it is in British Columbia, and are at risk restricted to British Columbia, grow- due to ecological changes occurring ing in a few sites in the Okanagan in their habitats. Valley, southeastern Vancouver Island What are they? Scarlet gaura (Gaura coccinea) is and the southern part of the Rocky ost of British Columbia’s grasslands an eye-catching member of the fire- Mountain trench. are found in the rainshadow of the weed family (Onagraceae), best view- With its lovely, feather-like spike- Coast and Cascade mountains, in ed just before evening when the lets, blue grama (Bouteloua gracilis) is Mareas where low rainfall and season- flowers open for pollination by night- a very attractive member of the al drought limit tree growth and allow flying insects. Its botanical name grass family (Poaceae). Unlike other grasses to dominate. Covering about comes from the Greek – gauros mean- grasses, blue grama is not easily 1.8 percent of British Columbia, grass- ing “superb,” and cocinnea meaning overlooked. Its aesthetic qualities lands are unique ecosystems that provide “scarlet.” This perennial grows east are alluded to by the species name habitat for a variety of vertebrates and of the Rocky Mountains in dry, open gracilis. The genus name comes from invertebrates, as well as common and grasslands. It is common in the Spanish explor- rare plants. Grasslands are highly varied prairie habitats from Alberta to These species ers Claudio and in B.C. due to the province’s diverse geol- Manitoba and south to Mexico depend Esteban Boutelou. ogy, topography and climate. The and Texas. In British Columbia, This perennial likes bunchgrass community is the most scarlet gaura is found in the on habitat dry, grassy hills extensive grass- Okanagan basin and with- protection where it forms land type, domi- Limited in grassland patches in the thick mats, grow- nated by blue- southern part of the Rocky and ing from short bunch wheatgrass suitable Mountain trench. rhizomes (under- stewardship (Elymus spicatus) habitat along Flat-topped broomrape ground stems). and Idaho fescue (Orobanche corymbosa spp. for survival. Blue grama is a (Festuca idahoen- with the mutabilis) is a member of common domin- sis), and found in continuing the broomrape family (Oroban- ant species of the North American hot valley bottoms chaceae), which is well known short grass prairie, which extends east in the Okanagan loss of our for its parasitism. The plants of to Manitoba and the eastern United basin, in the grasslands this genus gained their common States, and south to Mexico. In British Thompson basin, name from a British species that Columbia it is known only from a and in the middle puts these is parasitic on Scotch broom few sites in the Cariboo-Chilcotin Fraser River and species at (Cystisus scoparius). The botani- region of the Fraser River basin and lower Chilcotin cal name orobanche also describes in the southern part of the Rocky River valleys. A risk. its parasitic nature – in Greek, Mountain trench. few patches of orobos means “vetch” and anchien mountain grasslands grow at low eleva- means “to choke.” The species name What do they look like? tions in the southern Rocky Mountain corymbosa describes the shape of its carlet gaura is a lovely 20- to 60-cen- trench, while vast grassy parklands flat-topped inflorescence. Flat-topped timetre tall plant that bears many spread across the Peace River region. broomrape is an austere, elegant, flowers crowded on a long terminal On southern Vancouver island, a scatter- purple-tinted perennial, often found Sspike. Each flower is made up of four ing of Garry oak (Quercus garryana) in association with big sagebrush petals, ranging in colour from white meadows persist. (Artemisia tridentata) on dry grassy to red, and of four sharply bent back Among the many rare grassland slopes. It is parasitic on the roots of sepals (modified leaves next to the species in British Columbia, scarlet this and other plants and gets its petals), which move in a remarkably but- gaura, flat-topped broomrape and nutrients and water through special- terfly-like manner with the slightest blue grama clearly illustrate the sta- ized root organs called haustoria. breeze. The long stamens and styles (the tus of the province’s grasslands and Flat-topped broomrape is found east male and female sexual organs of the their inhabitants. Although common of the Cascade Mountains in Wash- plant) enhance the insect-like appear- in other provinces and in the United ington, south to California and east ance of the scarlet gaura, also called rape however, is easily identified by 0.5 mm its compact, many-flowered inflores- cence. It can be distinguished from the more common California broomrape 1 mm (Orobanche californica ssp. californica), by the shorter lips of its corolla. 1 cm Blue grama is a 10- to 50-centime- 2 mm 1 mm tre tall, densely tufted grass. Its leaves are up to 15 cm long, often crisp and 0.5 mm curly with flat blades. It usually bears 2 cm two showy, purplish blue spikes made up of 20 to 80 spikelets arranged in two rows. When ready to release seeds, 2 mm the comb-like spikes roll into a dis- 2 cm tinctive and graceful spiral. It is the only species of its genus in B.C.

What is their status?   ‒   are and restricted to a few sites locat-   ‒   ed in highly developed areas, flat- “waving butterfly.” Short, lance-shaped topped broomrape, blue grama and tions still exist? If they have survived, leaves are crowded below the inflores- Rscarlet gaura are on the provincial how much longer are they likely to last cence; the fruit is a diamond-shaped nut. Red List (species being considered for under current conditions? No other species of the genus Gaura is legal designation as Endangered or Population trends are not known found in British Columbia. Scarlet gaura Threatened). Flat-topped broomrape is for any of these three species. All that can easily be distinguished from other known from 13 sites in Canada, all can currently be assessed is their pres- grassland flora by its terminal spikes of restricted to southern B.C. Blue grama ence or absence in grassland habitats. colourful, fluttering flowers. has been found in only seven locations in Field work is needed to gather more As a true parasitic plant, flat- this province. Scarlet gaura is known information about them. Most of the topped broomrape lacks chlorophyll from only eight sites in B.C., four of known sites should be revisited, and and is white to purplish in colour. which are historical records dating from further surveys should be undertaken Deprived of their photosynthetic before 1950. Considering the transfor- to assess their status and provide role, the leaves are reduced to simple, mation the grasslands have undergone guidelines for conservation actions. alternate, brownish scales. This rela- during the last 50 years, can we reason- Except for one flat-topped broomrape tively small plant (5 to 12 cm tall) has ably assume that these historic popula- population that occurs in a protected deep, fleshy roots that obtain water area – Cathedral Lakes Provincial Park and nutrients from neighbouring – these plants are not protected in plants. The flowers are borne on short 2 cm British Columbia. Only a fraction of stalks in a compact inflores- the province’s remaining native cence. The petals are fused in grassland is protected. Churn a two-lipped corolla lined with Creek Protected Area, estab- purple strips; the five sepals lished in 1994, has been set are inconspicuous. The fruit up to conserve some of the is a many-seeded capsule that 1 cm austere beauty of the Cari- splits in two to release small, 2 cm boo grasslands. dark seeds.There are five other Through the Forest Prac- species of broomrape in tices Code, the Province of British Columbia, all restricted British Columbia has issued to the southern part of the guidelines to preserve biodi- province. Flat-topped broom- -  ‒   versity on a provincial scale. The Range Management Guidebook, plants are all changing the eco- Distribution of rare grassland plants which is part of that Code, provides logical niche needed by rare in British Columbia recommendations on how to manage grassland species. grassland habitats. Rare grassland Fire is a natural disturbance plants are also candidates for protec- that plants have adapted to and tion under the Managing Identified upon which some plant com- Wildlife Strategy under the Forest munities depend. Seasonal fires Practices Code. maintain grassy meadows, keep A few regulations found in the forest understoreys open and Range Act, such as protection of water- promote biodiversity. For the past Kamloops sheds, and seeding of exposed soil, 50 years, the control of seasonal Scarlet gaura Flat-topped broomrape provide some legislative protection fires that once naturally main- Blue grama for grasslands in the province. tained grassland habitats has The BC Ministry transformed the original of Forests regu- One-quarter ecology of these areas. Forest care of these rare organisms, our lates grazing rota- encroachment is another major ecosystems may become impover- tion and duration of British cause of grassland degrada- ished, and therefore less able to adapt on Crown lands, Columbia’s tion. Non-native species such as to environmental stress and change. which could help knapweed (Centaurea species), Rare species can be prove to be limit long-term plants are cheatgrass (Bromus tectorum) valuable indicators of environmen- impacts on ranges. considered and orchard grass (Dactylis glom- tal changes, and give us helpful These regulations erata) have now become estab- insights into the health of ecosys- do not apply, how- rare. lished in many places, replac- tems. For example, the total number ever, to the large ing native grassland species. of rare grassland species is a reflec- part of our grasslands that is found Because flat-topped broomrape, tion of the history and health of grass- on private property and on Indian scarlet gaura and blue grama are land habitats. Reserve lands. restricted to pockets of dry lands Scarlet gaura, bounded by forested ridges, there In the flat-topped Why are they at risk? is only a limited amount of suit- Okanagan, broomrape and lat-topped broomrape, scarlet able habitat into which they can blue grama all gaura and blue grama are at risk in expand. In addition, the low less than  reach the north- British Columbia because their genetic diversity of these small, percent of western limit of Fhabitat is disappearing. Although isolated populations limits their their range in grasslands are more endangered than ability to disperse and establish the historical B.C. These peri- any other ecosystems in B.C., they do themselves in new sites. With grasslands pheral popula- not get the public concern and atten- their very specific ecological tions may be tion they deserve and, therefore, they needs and the fierce competition remain in genetically dif- receive very little protection. in the warm grasslands, these a relatively ferent from core A long history of land use (and species depend on habitat protec- populations, and abuse) has converted the native grass- tion and stewardship for survival. natural state. thereby could add lands of southern British Columbia to to the genetic a mosaic of over-grazed rangelands, Why are they important? adaptability of the species as a whole. ever-expanding cities, immaculate ll living organisms have intrinsic Northern populations are particular- fields of alfalfa and ginseng, and pro- value by virtue of their existence ly important for dealing with global ductive orchards and vineyards. In and because of their contributions warming because they will be the the Okanagan region, less than 10 Ato the ecosystems they inhabit. One source for northerly expansion and percent of the historical grassland quarter of British Columbia’s plants are migration of plant species should the remains in a relatively natural state. considered rare, and each plays com- climate become too warm for south- Continued overgrazing, fire suppres- plex ecological roles, which we do not ern populations. sion and expansion of non-native yet fully understand. If we fail to take Another strong argument for preserving overall biodiversity is the potential medicinal properties of plants. Worldwide, studies in eth- nobotany (study of the traditional use of medicinal plants by people) show how extremely valuable plants can be. Rare plants are also impor- tant for scientific research and can help us understand some of the causes of rarity, allowing us to better manage biological diversity. But most of all, these plants add to the beauty of our grasslands and to the biological richness of the land.    ,       , What can we do?         . Derek Johnson photo t is not too late to protect the unique diversity of grasslands in British Columbia, but the constant threats to Ithese ecosystems mean that any delay in conservation efforts could bring irre- versible and disastrous results. Detailed field inventories in tar- geted areas are needed to locate new populations of these species and to provide crucial information on pop- ulation trends. Thorough field inven- tory may reveal that some species are naturally rare, whereas others are endangered because of human activi- ties. Further research would help us better understand the complex rela-  -              . tionships between the multiple com- Joyce Gould photo ponents of grasslands, providing us with tools for conservation. Habitat restoration, appropriate management strategies and protec- tion of sensitive and species-rich areas are ways we can improve, or at least maintain, the diversity of life around us. One option for keeping grasslands healthy is to limit the extent and intensity of grazing. Another is the re-introduction of fire through prescribed burning, which would help control extensive forest encroachment. BC Parks already uses prescribed fire as a tool to preserve grasslands and biodiversity.   -            . The provincial Weed Control Act William Van Dieren photo               ,               .   .    . Syd Cannings photo Syd Cannings photo Syd Cannings photo defines and lists all exotic species life they harbour and share your South Okanagan Conservation Strat- considered noxious, and requires all experience with others by joining a egy or the Okanagan-Similkameen occupants of land in B.C. to control local naturalist group or by partici- Parks Society. Support land acquisi- those weeds. Each forest district has pating in nature surveys. Learn how tion by private and government agen- a noxious weed plan, which can be to use field guides to identify grass- cies, such as The Nature Trust of B.C. consulted for guidance on the land plants and animals. Garden with or the Land Conservancy of B.C. All species of concern. native plants, maintain wildlife trees these actions can help stop the What can we do as individuals? Go in your backyard. Sponsor and sup- shrinking of the grasslands. Spread out and look around for natural port education and conservation pro- the word! Another piece of the world’s grasslands patches in your neigh- grams, such as the British Columbia biodiversity is disappearing, right here, bourhood. Enjoy the great diversity of Grasslands Conservation Council, the in our province.

       , : BC Conservation Data Centre Ministry of Environment, Lands and Parks PO Box 9344 Stn. Prov. Govt. Victoria, BC V8W 9M1 www.elp.gov.bc.ca/wld/cdc

       : Habitat Conservation Trust Fund PO Box 9354 Stn Prov Govt Victoria, BC V8W 9M1 www.elp.gov.bc.ca/hctf

    Forest Renewal British Columbia

 ---         .         “       ”, ..   ,         ,               

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