Rubus armeniacus is a flowering plant in the family Rosacea. An alternate scientific name for this species is Rubus discolor. The genus Rubus consists of more than 750 species and includes common and widely distributed plants such as blackberries, raspberries and roses (CABI 2015; Wikipedia contributors 2017). R. armeniacus is not native to North America but has spread from its origin in Armenia. The plant was introduced to Europe in 1835 and to North America in 1885 for its tasty fruit (CABI 2015) and is now commonly called the Himalayan blackberry.
Description:
R. armeniacus forms dense thickets of thick (~1 cm) stems that arise from a rooted base, grows upwards and reaches 3 m in height before arching back to the ground where it can grow horizontally (Soll 2004; CABI 2015). The stems are usually ridged, often four-angled, and are armed with curved prickles (Pojar & Mackinnon 1994). The compound leaves have 3 to 5 egg-shaped leaflets, are arranged alternately on stems, and are often evergreen in mild climates. The leaves are green and smooth above, and greyish and woolly below (Klinkenberg 2017). The white to pinkish flowers are small (~2.5 cm), stalked, and organized in clusters (Invasive Species Council of British Columbia 2017).
Ecology:
R. armeniacus is often found in open and disturbed sites such as meadows, forest edges, clear-cut areas, and along roadways (Soll 2004). This species grows in a wide variety of soil conditions and in areas with moderate rainfall. Its tolerance to a great variety of environmental conditions allows it to establish and grow quickly, suppressing the growth of other plant species. Native species can be excluded from these sites, resulting in a reduction of local biodiversity (Soll 2004; CABI 2015). In contrast to this negative ecological effect, R. armeniacus berries provide a good source of food for a wide variety of animals (birds, rodents, and humans). The thickets also provide protective cover for birds and small mammals from larger predators.
Reproduction and Dispersal:
Following the pollination of the female reproductive structures in the flowers, fertilization occurs and seeds are produced. The seeds are embedded in the fruits (or berries). A large number of seeds can be produced each year (up to 13,000 seeds/m2; CABI 2015). The animals that eat the berries help to disperse the seeds to new locations. R. armeniacus can also reproduce asexually. Vegetative (asexual) reproduction occurs when arching stems touch the ground and grow roots. Ultimately this forms daughter plants.
References cited:
[CABI] Centre for Agriculture and Bioscience International. 2015. Rubus armeniacus [original text by Florin, M]. In: Invasive species compendium. Wallingford, UK: CAB International. [accessed 2018 Jan 29]. https://www.cabi.org/isc/datasheet/116780.
Invasive Species Council of British Columbia. 2017. Himalayan blackberry, Rubus armeniacus. [accessed 2017 March 14]. http://bcinvasives.ca/documents/Himalayan_Blackberry_TIPS_Final_08_06_2014.pdf.
Klinkenberg B, editor. 2017. E-Flora BC: Electronic Atlas of the plants of British Columbia [eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [accessed 2018 Jan 29]. http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Rubus%20armeniacus.
Pojar J, MacKinnon A. 1994. Plants of coastal British Columbia: including Washington, Oregon & Alaska.
Vancouver: Lone Pine Publishing.
Soll J. 2004. Controlling Himalayan blackberry in the Pacific Northwest (Rubus armeniacus [R. discolor, R. procerus]). The Nature Conservancy. [accessed 2018 Jan 29]. https://www.invasive.org/gist/moredocs/rubarm01.pdf.
Wikipedia contributors. 2017. Rubus. Wikipedia, The Free Encyclopedia. [accessed 2018 Jan 29]. https://en.wikipedia.org/w/index.php?title=Rubus&oldid=766684686.
Invasive Species Council of British Columbia. 2017. Himalayan blackberry, Rubus armeniacus. [accessed 2017 March 14]. http://bcinvasives.ca/documents/Himalayan_Blackberry_TIPS_Final_08_06_2014.pdf.
Klinkenberg B, editor. 2017. E-Flora BC: Electronic Atlas of the plants of British Columbia [eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [accessed 2018 Jan 29]. http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Rubus%20armeniacus.
Pojar J, MacKinnon A. 1994. Plants of coastal British Columbia: including Washington, Oregon & Alaska.
Vancouver: Lone Pine Publishing.
Soll J. 2004. Controlling Himalayan blackberry in the Pacific Northwest (Rubus armeniacus [R. discolor, R. procerus]). The Nature Conservancy. [accessed 2018 Jan 29]. https://www.invasive.org/gist/moredocs/rubarm01.pdf.
Wikipedia contributors. 2017. Rubus. Wikipedia, The Free Encyclopedia. [accessed 2018 Jan 29]. https://en.wikipedia.org/w/index.php?title=Rubus&oldid=766684686.