BC Conservation Data Centre: Conservation Status Report
Rubus nivalis
snow bramble
| Scientific Name: | Rubus nivalis |
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| English Name: | snow bramble |
| Provincial Status Summary | |
| Status: | S3S4 |
| Date Status Assigned: | March 31, 2018 |
| Date Last Reviewed: | April 30, 2019 |
| Reasons: | A total of 21 historic and extant populations of Rubus nivalis have been documented in B.C. Two occurrences are thought to have good viability and two populations occur in provincial parks. Total population size for R. nivalis in B.C. is unknown, but has been estimated at hundreds or thousands of plants prior to forest harvesting at one location. Total range extent is approximately 48,000 square kilometres, with only 17,000 square kilometres in the central part of the range. The total area of occupancy is approximately 84 square kilometres. Short-term trends and long-term population trends are unknown, but Douglas-fir forests across the species' range have been extensively logged. Though it appears to tolerate some sun exposure, plants under canopy cover, in standing timber were much more robust than those in logged cutblocks. |
| Range | |
| Range Extent: | EF = 5000-200,000 square km (about 2000-80,000 square miles) |
| Range Extent Comments: | If the historical report from Nakusp is included, which is at the extreme eastern limit of the distribution of Rubus nivalis, the estimated range extent for the species in B.C. is approximately 48,000 square kilometres. However, the estimated spatial extent of occurrences in the central part of the range on east-central Vancouver Island and the Sechelt Peninsula is only 18,000 square kilometres. |
| Area of Occupancy (km2): | D = 20-100 square km (about 5000-25,000 acres) |
| Area of Occupancy Comments: | The estimated area of occupancy is approximately 84 square kilometres, using a 2km x 2km grid analysis. |
| Occurrences & Population | |
| Number of Occurrences: | BC = 6 - 80 |
| Comments: | A total of 22 populations have been documented in B.C. Six occurrences are historic and have not been observed since 1968. More inventory is needed as other populations could exist. |
| Number of Occurrences with Good Viability / Ecological Integrity: | U = Unknown what number of occurrences with good viability |
| Comments: |
Little information is available that can be used to rank known occurrences, but at least two locations (west of Robert's Creek and Mt. Elphinstone) have good viability, though the long term impacts of timber harvesting are not known. |
| Number of Occurrences Appropriately Protected & Managed: | None. No occurrences appropriately protected and managed |
| Comments: | Two occurrences (Alouette Mountain and Myra Creek) are in Golden Ears and Strathcona-Westin Provincial Parks. Occurrences in provincial parks are protected by the Provincial Parks Act, which prohibits removal, damage, or disturbance to natural resources except as authorized by a park use permit. |
| Population Size: | CD = 250 - 2500 individuals |
| Comments: | The number of individual plants was not reported from most sites, but in 1999, 20 individuals were observed west of Robert's Creek. In 2000, "hundreds, maybe thousands of plants" were observed at this location and in 2007, 5 subpopulations were reported (A. Ceska, pers. comm. 2000, Strathcona Forestry Consulting 2007). Also in 2007, 22 subpopulations were reported from Mt. Elphinstone (Strathcona Forestry Consulting 2007). |
| Threats (to population, occurrences, or area affected) | |
| Degree of Threat: | C = Substantial, non-imminent threat |
| Comments: | Most sites of occurrence are on lands managed for forestry where Rubus nivalis is subject to continued pressure from forest harvesting. At Mt. Elphinstone on the Sechelt Peninsula, plants in cutblocks had fair to poor vigour when compared to plants in standing timber which had active rhizomes and denser growth. Plants in logged areas displayed low density and sun-scalded, corrugated, reddish/purple leaves that had some brown scale and were much smaller than the leaves of plants under the forest canopy, which were lush, glossy and more vibrantly green (B. Smart pers. comm. 2001, Strathcona Forestry Consulting 2007). However, the long-term effects of forestry activities on Rubus nivalis are not fully known. Research in the United States suggests that the species may recover, provided soils are not damaged by harvesting activity. In experimental plots established within clearcut logged units in the western Cascade Mountains of Oregon, the distribution and cover of Rubus nivalis was approximately the same in the fifth year following logging and broadcast slash burning of the old-growth Douglas-fir forest as its distribution and cover prior to logging (Dyrness 1973). |
| Trend (in population, range, area occupied, and/or condition of occurrences) | |
| Short-Term Trend: | U = Unknown |
| Comments: |
Populations in B.C. have not been monitored; therefore short term trends are unknown. |
| Long-Term Trend: | U = Unknown |
| Comments: | Historical records that document changes to the abundance of Rubus nivalis over the last 200 years are not available, but populations may be declining due to extensive logging of mature forest habitats occupied by this species. |
| Other Factors | |
| Intrinsic Vulnerability: | U = Unknown |
| Comments: | Intrinsic vulnerability is unknown because the biology and reproductive success of this species have not been investigated. Reproductive success may be limited by the relative isolation of occurrences and if population sizes are small, they may be subject to decreased genetic diversity and viability. |
| Environmental Specificity: | C = Moderate. Generalist or community with some key requirements scarce. |
| Comments: | In B.C., Rubus nivalis is a forest-understory plant found in moist forests and glades at mid-elevations in the montane zone This species prefers moist, shade environments under the forest canopy, but will tolerate some sun exposure as it regenerates in logged areas. Though systematic assessments have not been undertaken in B.C, plants in cutblocks have displayed reduced vigour with sun-scalded leaves and less dense growth in comparison to colonies in standing timber (B. Smart pers. comm. Strathcona Forestry Consultants 2007). |
| Other Rank Considerations: | |
| Information Gaps | |
| Research Needs: | Almost no data are available regarding number of flowering stems, germination rates or seedling survival. Population viability and trends need to be monitored. Research on the effects of disturbance such as forestry activities on Rubus nivalis is also needed. |
| Inventory Needs: | Known sites need to be resurveyed and data collected on habitat, population numbers, condition and viability of the occurrence. New sites need to be searched for through targeted surveys of high potential habitat, at the correct time of year. |
| Stewardship | |
| Protection: |
Protection from forestry activities, through implementation of WHA's under the Identified Wildlife Management Strategy is the most important need identified. A primary objective should be to protect all known populations, as maintaining multiple populations will help to mitigate the effects of catastrophic loss at any one site. . |
| Management: | Clearcut logging should be avoided and silviculture plans in forested habitats should include canopy tree retention in order to sustain biological values and ecosystem functions. At Mt. Elphinstone on the Sechelt Peninsula, plants in logged areas appeared more vigorous if they were partially shaded by slash (B. Smart, pers. comm.). |
| Version | |
| Author: | Donovan, M. |
| Date: | January 06, 2009 |
| References | |
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Batten, R. 2018. Vascular plant GeoCAT range extent and index of AOO maps supporting status assessment 2017_18 for British Columbia Conservation Data Centre. March 2018. Victoria, BC. 450 pp.
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British Columbia Conservation Data Centre. Botany Program. 2000. Database containing records of rare plant collections and observations in the province of British Columbia.
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Dyrness, C. T. 1973. Early Stages of Plant Succession Following Logging and Burning in the Western Cascades of Oregon. Ecology: Vol. 54, No. 1, pp. 57-69.
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Strathcona Forestry Consulting. 2007. Summary Report: Rubus nivalis surveys (2007) - Mount Elphinstone (BCTS Powell River Operating Area). Prepared for BC Timber Sales (Strait of Georgia Business Area 370 Dogwood Street, Campbell River, BC V9W 6Y7).
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Please visit the website Conservation Status Ranks for information on how the CDC determines conservation status ranks. For global conservation status reports and ranks, please visit the NatureServe website http://www.natureserve.org/.
Suggested Citation:
B.C. Conservation Data Centre. 2009. Conservation Status Report: Rubus nivalis. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Jun 5, 2026).