United States Department of Agricu It ure Western Redcedar Forest Service -- Pacific Northwest Forest and Range Experiment Station A Literature Review Genera I Tech ni ca I Report PNW-150 Don Minore February 1983 EDITOR'S FILE COPY . .. s' B This file was created by scanning the printed publication. Mis-scans identified by the software have been corrected; however, some errors may remain. DON MINORE is plant ecologist, Forestry Sciences Laboratory, Pacific Northwest Forest and Range Experiment Station, Corvallis, Oregon. Abstract Contents Minore, Don. 1 Introduction 27 Diseases 1983. Western redcedar: A Seedling Diseases literature review. USDA For. Serv. 1 Occurrence and Gen. Tech. Rep. PNW-150, 70 p. Abundance Foliage Fungi Pac. Northwest For. and Range Root and Butt Rots Exp. Stn., Portland, Oreg. Range Volumes Stem Diseases This report is a comprehensive com- Trunk Rots pilation of information on western 3 Associated Plant Species Product Decay redcedar (Thuja plicata Donn) - its Trees occurrence and abundance; associ- Extractives and Decay ated plant species; morphology and Shrubs Birds and Mammals anatomy; products; medical aspects; Herbs 30 diseases; insect, bird, and mammal. pests; genetics; horticulture; physi- Major Communities 30 Genetics ology; ecology; mensuration; and si lvicu It ure. Management recommen- 12 Morphology, Anatomy, 30 Horticulture dations and an extensive list of and Composition references are included. Form 31 Physiology and Ecology Meteorological Keywords: Western redcedar, Thuja Crown, Branches, and plicata, silviculture, ecology, Foliage Influences physiology, products. Strobili and Seeds Fire Roots Soils Bark Nutrients and Nutrition Wood Asexual Reproduction Sexual Reproduction 18 Products Phenology Uses and Properties Regenerat ion Prices Shade Tolerance Lumber Succession Shakes and Shingles Growth Poles and Piling Productivity Pulp Veneer and Plywood 41 Mensuration Waste Utilization 45 Silvicu I tu re Extractives Seeding 24 Medical Aspects Nursery Practices Stand Culture and 24 Insects Improvement Bark Beetles Harvesting Wood Borers Defoliators 48 Discussion Seed and Cone Insects 48 Recommendations Miscellaneous Insects for Management Extractives and Insects 49 Acknowledgment 50 Common and Scientific Names of Trees 51 Lltera t ure CIted lntroduction Occurrence and Abundance The western redcedar is the only Range Thuja species native to western North America.J (Northern white- Western redcedar grows along the cedar grows in eastern North Pacific coast from northern Califor- America, and four other Thuja nia to southeastern Alaska (fig. 1). It species occur in the Orient.) These occurs sporadically at its southern members of the subfamily Thu- limit in Humboldt County, California, joideae of the Cupressaceae are where it is common only in the considered more highly evolved than lower Mad River drainage and the Libocedrus, Cupressus, Chamae- wet region south of Ferndale (Griffin cyparis, or Juniperus species (see and Critchfield 1972). Elsewhere Moseley 1943).3 Large western along the northern coast of Califor- redcedars reach ages of 800 to 1,000 nia, western redcedar occurs only in years, and some individuals in isolated stands on boggy habitats. eastern Washington may be 2,000 years old (Sharpe 1974). General at- North of the California-Oregon tributes of the species include a border, the natural range of western conical form with large and fluted redcedar broadens to include por- base in mature trees, drooping tions of the Cascade Range. On the branches, thin fibrous bark, and western slopes of the Cascades, small scalelike leaves arranged in redcedar grows from Crater Lake flat sprays (Sudworth 1908, Sharpe north (Boyd 1959, Little 1971). On the 1974). eastern slopes, it occurs north of approximately 44'30'N latitude Redcedar wood is valuable and used (Franklin and Dyrness 1973). The Figure 1. -The natural range of western extensively. Use of redcedar prod- redcedar populations of the redcedar (from Little 1971, Viereck and ucts is far ahead of the manage- Cascades and the coast meet occa- Little 1975). ment practices for replenishing the sionally in moist portions of the supply of high-quality timber from Willamette Valley, Oregon. Farther which most of those products are north, optimal growth and develop made. More efficient use of western ment are achieved near the latitud- redcedar and better management inal center of western redcedar's are needed; they can best be range - the Olympic Peninsula in achieved by using available Wash ing ton. knowledge as a base for further ad- vances. Considerable knowledge is North of Vancouver Island, western available, but it is scattered in redcedar is restricted to the Coast diverse publications under many Ranges and coastal islands. The subject headings and titles. This northern limits of its coastal range report summarizes most of the infor- are the northern and western shores mation in those publications for the of Sumner Strait on Kupreanof and scientists, administrators, and Kuiu Islands and the Petersburg foresters who participate in western vicinity on Mitkof Island (Harris and redcedar research, use, and Farr 1974) at approximately 56'30'N si Iviculture. latitude (see Andersen 1953). South of Petersburg, western redcedar oc- curs as an overstory dominant on lNomenclature for all northwestern plant former muskeg areas with shallow species is according to Hitchcock and water tables (Stephens et al. 1970). Cronquist 1973. Scientific names for It is common and important only far- trees mentioned by common name throughout the text are listed on ther south, however, near Ketchikan page 50. and Craig, in the intermediate types between bogs and upland forests ?Where information was derived from a (Neiland 1971). publication, but not specifically stated therein, the author's name is prefaced by "see" (e.g., see Little 1971). 1 Near the southern border of British Where sufficient precipitation is for practical Jorestry in Czechoslo- Columbia, a few scattered popula- present, temperature apparently vakia (Holubcik 1968). It has been tions of western redcedar occur be- limits the range of western redcedar. planted in Denmark and France tween the Coast Ranges and Selkirk Schmidt (1958) measured an abrupt since the 1860's (see Sgegaard Mountains, but the coastal range is decrease in length of the frost-free 1956b, Guinier 1951). Western essentially isolated from the interior period just above the upper eleva- redcedar plantations also have been range of the species. The northern tional limits of western redcedar, established in Italy (Minister0 limit of the interior range is on the western hemlock, and Douglas-fir on dell'Agricoltura e delle Foreste, Col- western slope of the Continental Vancouver Island. In southeastern lana Verde, Roma 1965). Redcedar Divide at 54'30'N latitude. The in- Alaska, the northern limits of has been grown in western Norway terior range extends south in British western redcedar are not correlated (Smitt 1950), but the northernmost Columbia through the Selkirk Moun- with rainfall or winter temperatures, stands on record are in Mustila, tains into western Montana and but they are between the 11.1" and Finland, at 60'41 'N latitude (Art- northern Idaho (Boyd 1959). The 11.7"C (52" and 53°F) mean summer sybashev 1939). southern limit of the interior range temperature isotherms (Andersen is in western Montana's Ravalli 1953, 1955a). Average annual tem- Western redcedar has been planted County at 45'50'N latitude (see Little peratures in inland portions of the extensively in New Zealand (see 1971). With the possible exception - redcedar range are lower than those Perham 1938, Hocking and Mayfield of a few trees east of the Continen- along the coast (see Boyd 1959). 1939, Ranger 1945, Streets 1962, and tal Divide near the upper end of St. Weston 1971). It has also been suc- Mary's Lake, the eastern limit is Western redcedar is often grown cessfully grown at higher elevations near Lake McDonald in Glacier Na- outside its natural range. In the in Tasmania, but it grows relatively tional Park (Aller 1960). United States, planted trees grow as slowly in Kenya (Streets 1962). The far north as Juneau, Alaska (Harris species has shown little promise in Western redcedar grows from sea and Farr 1974), and western red- the Union of South Africa (Streets level to 915 m (3,000 ft) in south- cedar is occasionally cultivated as 1962) or in central Honshu, Japan eastern Alaska (Viereck and Little an ornamental tree in the Middle (see Kawada and Yamaji 1949). 1972). In British Columbia, the eleva- and North Atlantic States (Sargent tion range is higher - from sea 1933). Redcedars have been Volumes level to 1200 m (3,900 ft) (Anderson cultivated as ornamentals in the 1961). Interior redcedar is found Ukraine since 1870 (Unasylva 1950, Western redcedar is an important from 320 m (1,050 ft) near Orofino, Perepadya 1971). They are also used commercial species in much of its Idaho (personal communication, as ornamentals and hedge trees in natural range. In North America, an Charles A. Wellner, Forestry southern Australia (Streets 1962). estimated volume of 154 billion Sciences Laboratory, Moscow, Western redcedar hedges are widely board feet (Scribner rule) exists in Idaho), to 2100 m (7,000 ft) (Boyd used in Britain (Hubbard 1950) and live western redcedar trees that are 1959). The greatest range in eleva- in Switzerland (see Keller 1974). at least 25 percent sound (Bolsinger tion occurs in Oregon, however, 1979). More than three-fourths of where western redcedar occurs from For years western redcedar has this volume (120 billion board feet sea level to 2300 m (7,500 ft) at the been used in practical forestry in by Bolsinger's estimate) occurs in rim of Crater Lake (Sudworth 1908, England, Ireland, Scotland, and British Columbia. Within British Co- Bowers 1956). Wales (see Keatinge 1947, Zehet- lumbia, 86 percent of the western mayr 1954, Ovington and Madgwick redcedar volume is found in coastal Coastal populations of western 1957, O'Carroll 1967, Aldhous and areas (British Columbia Forest Ser- redcedar receive from less than 89 Low 1974, Priest 1974, Carey and vice, Inventory Division 1967).