Plant Data Sheet
Blackcap raspberry, White bark raspberry, Cut leaf
Blackberry, or Western Raspberry
Rubus leucodermis
Range
Black cap raspberry (black cap hence forth) has a large
distribution range that extends from
Climate
Black cap prefers full to dappled sun and moist soil. Can not tolerate saline or windy conditions and has a low drought tolerance.
Local occurrence
In
Habitat preferences
Black cap can be found in fields and on open or wooded hillsides from lower to more moderate elevations.
Plant strategy type/successional
Black cap is found in disturbed areas and has a high fire tolerance. If soil moisture is appropriate then this species could be a colonizer. Its specific strategy is to grow tall (up to 6’) and produce an abundance of seed. This would be an early successional species.
Associated species
Black
cap has been found to be associated with the Bigleaf
Maple complex. This complex includes big leaf maple (Acer macrophyllum), salmonberry (Rubus
spectabilis), trailing blackberry (Rubus ursinus),
sword fern (Polystichum munitum)
and bracken fern (Pteridium aquilinum). Other shrub species that may
occur with varying abundance are red elderberry (Sambucus
racemosa), devil's club (Oplopanax
horridus), redosier
dogwood (Cornus stolonifera),
salal (Gaultheria shallon) and stink currant (Ribes
bracteosum). Red alder (Alnus
rubra) is a minor component in some stands.
Black cap has also been found in Giant Sequoia (Sequoiadendron giganteum) groves.
Collected
Black cap may be collected as seeds, divisions, and cuttings.
Collection restrictions or guidelines
Since conservation status is not currently tracked, there are no government collection restrictions at this time. Ideally collection for seeds would occur when seeds are ripe. Fruit period begins in summer and extends through fall. Cuttings of half-ripe wood maybe collected in July. Tip layering may be started in July to be planted out in the fall. Divisions can be collected in early spring before leaf out or before leaf drop in the fall.
Seed germination
Seeds have a cold stratification requirement of at least 30 days at 3o C. There has been some research showing that treatment with sodium hypochlorite may simplify seed germination.
Seed life
Specific information about seed life for black cap was unavailable. Since seed production is abundant and vigor is high, recommend yearly collection.
Recommended seed storage conditions
Specific information about seed storage and viability for black cap was unavailable. Recommend dry cold storage.
Propagation recommendations
Black cap may be propagated by a variety of methods. Since seed vigor is high this would be the easiest and cheapest method. They can also be propagated from cuttings, sprigs and bare root.
Soil or medium requirements
Black cap is adapted to a variety of soil types. It has a minimum pH tolerance of 5.6 to a maximum of 7.3. No inoculum is necessary.
Installation form
Recommended installation form is seeds. This material is both easily transported and relatively cheap. Divisions and bare roots would be also be relatively cheap but would require correct timing logistics to be worked out in advance.
Recommended planting density
Recommended planting densities range from a minimum if 1200/ acre to a maximum of 4800/ acre.
Care requirements after installed
Care should be given to locate newly planted black caps in an ideal location. They have medium water requirements with low drought tolerance and a minimum of 120 frost free days. They are intolerance of anaerobic conditions as well as windy locations. If located properly, no special care is required after installation.
Normal rate of growth or spread
Black cap is a perennial arching vine. It grows at a rapid rate during both spring and summer creating dense hedges. The blossoms and fruit appear on two year old canes that die back at the end of the season.
Sources cited:
The
http://biology.burke.washington.edu/herbarium/imagecollection.php?Genus=Rubus&Species=leucodermis
Plant for a Future: Edible,
medicinal and useful plants for a healthier world. Non-profit
http://www.ibiblio.org/pfaf/cgi-bin/arr_html?Rubus+leucodermis
USDA: Natural Resources
Conservation Services; Plant Characteristics
http://plants.nrcs.usda.gov/cgi_bin/plant_attribute.cgi?symbol=RULE
International
Society for Horticultural Science
http://www.actahort.org/books/262/262_42.htm
Nature Conservancy
http://www.natureserve.org/explorer/servlet/NatureServe?searchName=Rubus+leucodermis
Data compiled by
Nancy Toenyan
April 13, 2006