R E S E A R C H A R T I C L E ABSTRACT: Culturally modified trees (CMTs) are trees with scars that reflect human utilization of for- ested ecosystems. Some CMTs can reveal unique knowledge of native cultures and insight to peoples’ subsistence and land use in the past, and are mostly to be found in protected areas since they contain very old trees. In this study, we examine attributes and the spatial and temporal distribution of bark- • peeled trees, and present forest structure in two remnant ponderosa pine forests (Pinus ponderosa P. & C. Lawson) in western Montana. We also wanted to use an alternative method of dating CMTs and Ancient Bark- initiate a broader discussion of threats to such trees and needs for sustaining and protecting them. In total, 343 bark-peelings were recorded on 274 living and dead trees. Our results show that only certain peeled Trees in trees were selected for harvest. Nearby trees of similar size and age were not used. The age estimation indicates that the bark-peelings were performed from the mid 1600s until the early 1900s. Today the the Bitterroot forest at both study areas is generally low in density and all-aged with very old individual trees. They consist of a mosaic of uneven-aged tree groups and individual trees of various ages. We conclude that the abundance and density of bark-peeled trees at the study areas exceed values reported in most other Mountains, North American studies (formally protected forests included), that the two areas represent different harvest areas for ponderosa pine inner bark, and that CMTs need to be recognized both as ecologically Montana: Legacies and culturally valuable features of old ponderosa pine forests. of Native Land Use Index terms: bark-peeling, Culturally Modified Trees, forest history, native people, Pinus ponderosa and Implications for INTRODUCTION (Pinus ponderosa P. & C. Lawson), found Their Protection in relatively dry forest habitats throughout The cultural history of forests and how much of the western United States (Oliver Torbjörn Josefsson1,5 people traditionally have interacted with and Ryker 1990). Several studies have been forest ecosystems worldwide has been carried out on bark-peeled ponderosa pines, 1Landscape Ecology Group receiving increasing attention during recent most of them emphasizing their importance Department of Ecology and decades (Agnoletti and Andersen 2000; as a food source (see Martorano 1981; Environmental Science Agnoletti 2006). An important advance Swetnam 1984; Merrell 1988; Reddy 1993; Umeå University in this field is the study of culturally Kaye and Swetnam 1999). Other studies SE-901 87 Umeå, SWEDEN modified trees (CMTs; i.e., trees with scars, underline their value as unique living ar- Elaine Kennedy Sutherland2 marks, or carvings that reflect past human tifacts, reminding us about related means utilization of forested ecosystems) that of subsistence, such as the use of fire to Stephen F. Arno3 are found in many old forests worldwide clear away undergrowth around camping 4 Lars Östlund (Östlund et al. 2003; Turner et al. 2009). grounds and travel routes, and to attract 2U.S. Forest Service, Rocky Mountain Since CMTs are old, living artifacts, they game to certain areas – activities that may Research Station eventually die and disintegrate – lately at have had a substantial impact on the for- Forestry Sciences Laboratory an accelerating rate. One specific type of est ecosystem (Östlund et al. 2005; Arno 800 E. Beckwith Avenue CMT found in North America and north- Missoula, MT 59801 et al. 2008). At present, the survival of 3U.S. Forest Service, Rocky Mountain ern Europe is bark-peeled trees. Just as ponderosa pines with bark-peeling scars Research Station – retired the people encountered by the Lewis and as well as other CMTs is threatened by 5755 Lupine Lane Clark expedition in 1805 along the Lolo declining tree vigor related to competition Florence, MT 59833 Trail in western Montana (Moulton et al. from ingrowth of younger trees, bark beetle 4 Swedish University of Agricultural 1988), many native groups throughout the outbreaks, wildfires, decay, and timber and Sciences northern hemisphere have made use of the firewood harvesting (Arno et al. 2008). This Department of Forest Ecology and nutritious inner bark from coniferous trees is unfortunate, if not tragic, because study Management th Umeå, SWEDEN up to the early 20 century (Krashennikov of CMTs in situ reveals unique knowledge 1972; Swetnam 1984; Zackrisson et al. of native cultures and insight to people’s 2000; Prince 2001; Östlund et al. 2004; subsistence and land-use activities in the • Mobley and Lewis 2009). The inner bark past. It might also be viewed as neglect was collected in a manner non-lethal to the or abandonment of readily recognizable 5 Corresponding author: trees, but leaving a distinctive, permanent artifacts of native cultures. [email protected]; +46 90 786 6092; Fax +46 90 786 670 scar which can be dated using dendrochro- nological (tree ring) methods (Swetnam CMTs in the United States are protected by 1984; Zackrisson et al. 2000). law and regulation, and research performed on them must conform to those laws and Natural Areas Journal 32:54–64 In North America, perhaps the most com- regulations. CMTs are protected by the monly used trees were ponderosa pine National Historic Preservation Act, and 54 Natural Areas Journal Volume 32 (1), 2012 must be treated as if they were on the Na- CMTs by measuring injury depth; and (4) they are known to contain large concen- tional Registry of Historic Places. In land to initiate a broader discussion of threats trations of bark-peeled trees and, judging management planning, under the National to CMTs and needs for sustaining and from the scarcity of old stumps, the forest Environmental Policy Act, the protection of protecting them. has been subjected to only a minor amount CMTs is defined under the Archeological of tree cutting. Resource Protection Act. Additionally, the METHODS AND MATERIAL American Indian Religious Freedom Act, The first study area is located on the steep Protection and Enhancement of Cultural slopes above Fales Flat, a native camping Environment (EO 11593), Indian Sacred Location of study areas area along the Nez Perce Fork of the West Sites (EO 130007), and other regulations Fork Bitterroot River. Large, old ponderosa all direct federal agencies to preserve and The study was carried out in two areas pine trees border a stream-side meadow protect traditional properties such as bark- situated along two tributaries of the West (Fales Flat) and extend up the south- and peeled trees. However, not all personnel Fork of the Bitterroot River in southwest- west-facing mountain slopes that rise above involved in land management activities ern Ravalli County, Montana (Figure 1). (Figure 2a). Up to the mid 19th century, are aware of CMTs; so, for example, in The study areas are located on the West Fales Flat was used as a camp site by Nez wildfire suppression CMTs may be dam- Fork Ranger District of the Bitterroot Perce people travelling eastward across the aged. Many federal lands are part of many National Forest. They are subject to an vast expanse of rugged ridges and canyons Tribes’ traditional use areas, and before any “inland Pacific-influenced climate” with on their way to the buffalo (Bison bison research can be undertaken, the proposal is mean annual precipitation of about 550 L.) hunting grounds on the high plains frequently reviewed by a Tribal council to to 600 mm and mean January and July east of the Continental Divide (Koeppen consider the acceptability and value of the temperatures of about -4 ˚C and 18 ˚C 1996). The actual study area encompasses proposed research to the Tribe. (Arno 1979). Summers are typically dry approximately 85 ha of steep slopes rising with low relative humidity. The terrain is from 1550 m at the campsite to about 1780 A typical method to determine the bark- heavily forested and consists of highly m in elevation. The second study area is peeling dates is by using an increment dissected steep mountain slopes and nar- situated in the flat bottom of a narrow valley borer to extract a series of pencil-size row canyons and valleys. Soils are coarse, at Hughes Creek, about 20 km southeast of cores of the growth-ring sequence at the rocky, and shallow, and are derived from Fales Flat (Figure 2b). It consists of about edge of the original scar. The cores are granite and a mixture of volcanic strata 90 ha of semi-open forest at an elevation then examined to find the position of the (Alt and Hyndman 1986). The composi- of about 1550 m. This vicinity was histori- bark-peeling scar in the annual rings. This tion and structure of the conifer-dominated cally utilized by native peoples, probably allows accurate dating of bark-peelings forest was historically shaped by wildfires for subsistence and as part of the travel (Swetnam 1984). Even though increment of variable frequency and severity. Since route up the West Fork valley to mountain coring of coniferous trees, such as pon- the early 20th century, fire suppression has passes providing access to the Salmon derosa pines, is not dangerous to the trees altered historic fire patterns (Arno et al. River canyon to the south. The area was (the small holes rapidly fill with pitch), 1995). The two sites were chosen because subjected to considerable prospecting and coring is unquestionably a physical inva- sion of the tree. Some Native peoples find the research activities acceptable, and the resulting detailed historical information about their ancestors valuable, and some do not. Descendents of native people are increasingly aware of the relationship between CMTs and use of them by their ancestors.