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PRESERVING AND IN A SEA OF A CONSERVATION CHALLENGE IN THE ARTICLE AND PHOTOGRAPHS BY ED ALVERSON

“We ride a few miles in nature’s Wilderness still persists in the rugged ᮡ Upland in early spring with park, the most enchanting mountains but the lowland has Ranunculus occidentalis bordered by scenery of the kind I ever saw, the a different story to tell. Where there is Oregon white oak (Quercus garryana). now a sprawling expanse of developed ground, the , all beautiful; – the cities of Vancouver, stimulate growth of such as camas such is the variety and beauty of Seattle and Portland, as well as outlying lily ( spp.), facilitate the harvest the as to present themselves farms and industrial – there were of and acorns (particularly from in every step; it is like a once magnificent conifer forests, punctu- Oregon white oak or Garry oak, Quercus , a flower garden, indeed, ated by contrasting areas of prairies and garryana) and prepare small plots of on a large scale, to an extent open canopied savannas or ‘oak ’. ground for cultivation of tobacco. The resulting landscape was a mosaic of forest, unmeasured, and it hardly seems Before settlers of European descent and prairie which supported a right that our horses should step.” arrived, the valleys west of the Cascades great diversity of and wildlife habi- (which include the of tats, a model of a sustainable partnership Rev. George Gary Oregon, the Puget Trough of between humans and nature. Oregon City, Oregon, May 1845 and the Georgia Basin of southwest ) were well populated by From the European perspective, the orthwestern , native peoples. These people fished for Arcadian nature of the lowland landscape where the continent meets the salmon, hunted wild game and gathered in the Pacific Northwest comes through NPacific Ocean, is a region of great , bulbs, seeds and berries in the descriptions of early explorers from ecological contrasts. Within the province – from an abundant native landscape. the late 1700s and early 1800s. The of British Columbia () and the Scottish botanist David Douglas, who states of Washington and Oregon (USA), Prairies and savannas were the most explored the region between 1825 and snowy mountains rise above fertile valleys. important source of food plants to the 1834 in search of seeds of potential new Extremes of climate, from to native people. They were also the habitats garden plants, described the Willamette desert, temperate to alpine, create a most subject to their management. In Valley in August 1826: “Country undu- complex landscape of diverse habitats. particular, fire in prairies was used to lating, rich, light, with beautiful

April 2005 PLANTTALK 40 23 ᮤ Golden paintbrush (Castilleja levisecta), much of the remaining prairie landscape. a rare endemic federally listed as endan- By the mid-20th century, the conversion gered, survives at only 12 sites. was nearly complete. Of the original 700,000 ha (1,700,000 acres) of prairie solitary and pines interspersed and savanna habitat that existed in the through it…” Douglas further observed mid-1850s less than 1% remained. As the the extent to which fire influenced the modern age unfolded, nobody seemed to : … “and must have a fine notice the loss. effect, but being all burned and not a single blade of grass except on the Fortunately, in recent decades, a small margins of rivulets to be seen”. The land- band of conservationists has ‘rediscov- scape turned from black to green after the ered’ the prairies within this sea of forest, fall and winter , as described by the and have worked hard to conserve this ‘mountain man’ James Clyman when he landscape which so impressed the early travelled through the same region in May explorers such as David Douglas. One 1845: “I … was highly pleased with the example of this renewed attention is a beautiful variety of hill and valley so softly recently completed assessment of the bio- valled and intermingled with hill and dale diversity of the Willamette Valley-Puget as likewise timber and prairie all luxuri- Trough-Georgia Basin ecoregion (map, antly clothed in a rich and heavy coat of p. 26). It begins with a description of the vegetation and litterally clothed in flow- prairies and savannas and their biological ers the upland in yellow and the valleys in significance, which underscores why they purple. The quantity of small flowering are such important islands of diversity in vegettiles is very remarkable and beyond the Pacific Northwest’s sea of forest. conception.” Ecologists have classified the plant com- munities in the Willamette/Puget/ under threat Georgia ecoregion associated with prairies and savannas, representing different As white settlers displaced the native points along moisture and successional people from their traditional homelands, gradients. Seasonal wet prairies (usually the economic imperatives of the settlers found on heavy clay ) and associated meant the end of the prairies and savan- vernal pools represent the wettest end of nas. The settlers rapidly converted the the moisture gradient. Upland prairies open prairies to fertile agricultural land. They eliminated the periodic fires that ᮢ checkermallow (Sidalcea had kept the prairies and savannas open, campestris), Willamette Valley endemic. and in this temperate, often rainy climate, the result was more forest. Their abundant cattle, sheep and pigs foraged in areas not cultivated, depleting the grazing-sensitive native grasses and wild- flowers, which were largely replaced by introduced plants from Eurasia.

The economic wealth that the land produced encouraged the growth of towns and cities, which further claimed

ᮤ Tolmie’s mariposa lily (Calochortus tolmiei), widespread in prairie & savanna.

24 PLANTTALK 40 April 2005 are freely draining in the winter, have the butterflies, Western Meadowlark, ᮤᮡ The different types of prairie: best soils and have been largely converted Western Gray Squirrel, several species of From left to right: Wet prairie in the to farmland. Herbaceous balds and bluffs endemic pocket gophers and reptiles such summer dry with Deschampsia are associated with bedrock outcrops, and as Gopher and Sharp-tailed snakes. cespitosa as the dominant native grass, are subject to extreme summer . near Eugene, Oregon. Savannas have scattered oaks and a In April the floral display in the prairies ground similar to upland prairies but and savannas swings into full gear, with A herbaceous bald with parasitic mistle- grade into oak which support yellow buttercups (Ranunculus occidentalis), toe growing on Oregon white oak, near a moister flora dominated by shrubs. pink shooting stars (Dodecatheon hender- Corvallis, Oregon. sonii), white saxifrage (Saxifraga integri- Prairies and savannas originally only folia) and white Oregon fawn lilies with Oregon sunshine occupied a small proportion of the land (Erythronium oregonum) brightening the (Eriophyllum lanatum), Willamette Valley (most of the rest was coniferous forest) landscape. In May the prairies are often west of Eugene, Oregon. but they contributed significantly to the filled with sheets of purple camas lilies floristic diversity of the region. In fact, (), accentuated with A vernal pool with Fragrant popcorn- 350 native taxa are generally larkspurs (Delphinium spp.), pink sea flower (Plagiobothrys figuratus), in restricted to prairies, savannas and associ- blush (Plectritis congesta), and yellow Basket Slough National Wildlife Refuge, ated oak woodlands in the Willamette/ balsamroot (Balsamorhiza deltoidea). Peak Willamette Valley, Oregon. Puget/Georgia ecoregion. Graminoids are diversity of flowering species is in late dominant throughout the year, with spring; a single square metre of high qual- Camassia quamash in bloom on gravelly seasonal displays of wildflowers. For ity prairie may support over 20 species of glacial outwash soils, Washington. example, 42 species of native grasses are native plants. Increasing summer drought associated with prairie, savanna and oak in July and August brings matura- PRESERVING PRAIRIES AND SAVANNAS habitats, as well as 75 species tion and vegetative dormancy, along with IN A SEA OF FOREST of Asteraceae and 30 species of Liliaceae. the burn season, but a few composites The flora includes 32 endemic or near- (Aster spp., Grindelia integrifolia) and endemic taxa. Many of the endemics are umbels (Perideridia and P. o r e - ᮢ Kincaid’s lupine ( sulphureus threatened by habitat loss; 20 of them are gana) flower into late summer and fall. subsp. kincaidii), a rare endemic and considered globally ‘at risk’. federally listed threatened species, in upland prairie, Willamette Valley, Oregon. The prairies and savannas are also home The conservation challenge to many declining wildlife species, such as the Fender’s Blue and Valley Silverspot Just as the prairies and savannas of the Willamette/Puget/Georgia ecoregion ᮢ The rare endemic white rock lark- were important to native people, the spur (Delphinium leucophaeum) survives botanical community of the region has in herbaceous balds and on roadsides. come to appreciate the beauty and diver- sity that these habitats bring to the region. With the start of conservation efforts has also come a better appreciation of the challenge to preserve this heritage for future generations.

Habitat inventories have shown that most existing prairie remnants are small, less than 25 ha in size, and only a few are over 100 ha. Conservation efforts are complicated by land ownership patterns, as only small percentages of the total land area (no more than 5–10%) are in public ownership.

April 2005 PLANTTALK 40 25 Maintaining native vegetation in these The results of this planning yielded a few remnants is also a challenge. Many ‘portfolio’ or network of sites that best Eurasian weeds, such as bentgrass represents the native species and ecosys- (Agrostis capillaris), velvet grass (Holcus tems. The aim of the assessment was to lanatus), false dandelion (Hypochaeris identify sites where the greatest number radicata) and oxeye daisy (Leucanthemum of high quality habitats and rare species vulgare), are often abundant in prairie occur together and so should be the high- vegetation. Especially problematic are est priority sites on which to focus con- woody plants such as broom (Cytisus servation resources. And by working to scoparius), blackberry (Rubus armeniacus) protect a portfolio of sites that most effi- and hawthorn (Crataegus monogyna), ciently conserves the region’s , which even without disturbance can the conservation community can both completely take over prairie remnants. maximize efficiency and minimize con- flict with other social and economic Furthermore, prairies and savannas have demands on the landscape. also been colonized by native trees in the absence of fire or other disturbance, Several dozen important prairie and particularly by conifers such as fast-grow- savanna sites have already been protected ing Douglas-fir. Many former oak savan- in reserves by federal, state, local and pri- nas and woodlands have developed into vate non-profit agencies. While most of conifer forests, where the skeletons of these remnants are small, from 10 to 200 massive, formerly open-grown oaks slowly ha (25 to 500 acres), they include some ᮡ Nelson’s checkermallow (Sidalcea decay in the moist shade of the fir forest. of the most important remaining habitats nelsoniana), a rare endemic and federally So while typical protection measures, for rare endemic prairie plants. listed threatened species, at Bald Hill such as creation of reserves, might prevent Park near Corvallis, Oregon outright habitat destruction from devel- Even if protection from development can opment or , active stewardship be accomplished by designating reserves, ᮢ Ecoregions of Northwest North of reserves is needed to ensure the long- the biodiversity assessment identified the America term survival of native prairie and savanna expansion of invasive species, and the species. absence of fire from that were historically maintained by fire, as the Montane The task of conserving prairie most important and widespread threats Cordillera Canadian Rocky and savanna habitats in the to prairies and savannas. Mountains North Cascade Willamette/Puget/Georgia and Pacific Ranges B R ecoregion has fallen to a vast Returning fire to the landscape is an C I T O LU I S M H number of federal, local and important but challenging strategy. The B I A non-profit agencies and orga- city of Corvallis, Oregon, has a large nizations. Without prioritiza- open space system managed by the city

Okanagan tion and coordination, alloca- parks department with important exam-

tion of scarce resources – of ples of prairie and oak woodland, as well

CANADA both money and land – might as populations of rare plants. Grant fund- not be as efficient as possible. ing has supported efforts to clear Willamette Valley USA Identifying conservation encroaching brush and saplings from Puget Trough Northwest priorities was the primary an oak savanna remnant. The Corvallis Georgia Basin motivation for the Wash- Fire Department has been enlisted to ington and Oregon chapters undertake prescribed burns in oak savan- WA of The Nature Conservancy, na habitat in the city’s Bald Hill Park. S HI N P G along with Nature Conser- A C T O I F I West N C O C Cascades vancy of Canada and many By first clearing the brush and removing E A N Columbia Plateau other agency partners, as they excessive fuels, it is again possible to have completed the biodiversity a low intensity underburn which reflects

Map courtesy of The Nature Conservancy assessment for the Willa- the behaviour of most fires in the historic mette Valley, Puget Trough prairie/savanna landscape. This is just Middle Rockies – and Georgia Basin. While one of many examples of prescribed OR E Blue Mountains G this assessment encompasses burning that has occurred (though on a O N

all ecological systems present small scale) at many other sites in the

Modoc in the ecoregion, the prairies region. The results vary from site to site, 0 20 40 60 80 100 Miles Plateau & East and savannas are a major but a consistently observed response is Cascades focus. that native herbaceous plants increase 0 50 100 150 200 Kilometres their flower and seed production after a

26 PLANTTALK 40 April 2005 PRESERVING PRAIRIES AND SAVANNAS IN A SEA OF FOREST

Where to go to see native prairies and savannas in the Willamette Valley, Puget Trough and Georgia Basin Oregon: • West Eugene Wetlands, Eugene • Finley National Wildlife Refuge, 10 miles S of Corvallis • Bald Hill Park, 3 miles W of Corvallis • Basket Slough National Wildlife Refuge, 10 miles W of Salem fire. Most invading woody plants will be ᮡ The beautiful spring landscape of • Camassia Natural Area, West Linn top-killed by fire but (except for conifers) oak-covered hills, with Iris tenax Washington: usually re-sprout the following year. • Ridgefield National Wildlife Refuge, Cultivating greater appreciation among 15 miles N of Vancouver Managing non-native species is both a the general public is also important. In • Mima Mounds Natural Area Preserve, logistical and ecological challenge. For a the southern Puget Sound region, near 12 miles SW of Olympia given site, priority species for control Olympia, Washington, several good • Scatter Creek Wildlife Area, must be identified and treatments – hand examples of gravelly glacial outwash 14 miles S of Olympia removal, mechanical treatment, herbicide prairies with mysterious ‘Mima Mound’ • Washington Park, Anacortes application – sustained. Many non-native topography are found on state-owned • Moran State Park, Orcas Island species are persistent, both from under- reserves. Every May, the public is invited British Columbia: ground parts or a seed bank, and treat- to visit the prairies during the height of • Mount Hill Park, 6 miles W of ments must continue or the gains that are bloom of camas lilies, as part of the annual Victoria made will quickly be lost. Prairie Appreciation Day. • Mount Tzuhalem Ecological Reserve, 3 miles NE of Duncan Successful projects are often those that In British Columbia, the few remaining combine multiple public benefits with areas of native prairie and savanna habitat conservation goals. In Oregon, the West are under great threat of development. As Ed Alverson has 25 years’ experience Eugene Wetlands project (a partnership a result, 59 prairie-associated plant taxa as a botanist in the Pacific including the City of Eugene, Bureau of are considered to be at risk in BC, many Northwest and works as a Stewardship Land Management and The Nature of which occur nowhere else in Canada. Ecologist for The Nature Conservancy. Conservancy) is protecting and managing The Garry Oak Ecosystems Recovery existing remnants of wet prairie, as well as Team has produced a Recovery Strategy ᮢ Collecting seeds of native grasses, restoring adjacent wet prairies; over 200 for Garry Oak and its associated ecosys- TNC Kingston Prairie Preserve, acres of wetland and upland prairie have tems and at-risk species. And there is Willamette Valley, Oregon. been restored so far. At the same time the already research showing that existing project is improving water quality and remnants can be improved by removing providing recreation and education non-native species, followed by prescribed opportunities, all in the midst of an burning and seeding of native species. industrial urban setting in which limited development is also permitted. Achieving success with long-term conser- vation of the prairie/savanna landscape will require education, appreciation and action, at a variety of scales – from indi- vidual citizens working on their own local natural areas, to agencies and organiza- tions working across state and even national boundaries to develop innova- tive conservation strategies and recover endangered species. Working to preserve these islands of diversity will help to develop and maintain a sense of place. O

ᮤ Wet prairie in the fall after woody vegetation has been removed and just after a prescribed burn.

April 2005 PLANTTALK 40 27