|Berries and leaves of Rubus flagellaris|
Willd. 1809 not Hook. & Arn. 1835
Rubus flagellaris has low-growing stems that range from 8–15 feet (2.4–4.6 m) long, and flowering stems that can grow up to 4 feet (1.2 m) in height. It can grow as a woody vine or low growing shrub. The young stems are green with a scattered arrangement of hairy prickles. The old stems are brown, woody and have hard prickles in comparison to the young stem. Sometimes the tips of the young stems root into the ground and form vegetative offsets.
The plant has an alternate compound leaf arrangement, with mostly three, but sometimes five leaflets attached. The margins of the leaves are serrated while the leaves show a palmate venation. Each leaflet is ovate, approximately three inches (75 mm) long and one inch (25 mm) wide. The leaflets are green on top, but pale green on the underside. One leaflet of a set is connected by a petiole to the stem while the other leaflets in the set are connected to that terminal leaflet.
The plant produces a five-petaled white flower, each flower about one inch (25 mm) in diameter with five petals. The flowers exhibit a terminal inflorescence with one to five flowers per young stem. The flowers are hermaphrodites and have both female and male sex organs. There are five sepals, green in appearance, lanceolate in shape. The ovaries exhibit a superior position relative to the sepals and petals. Several stamen surround a cluster of carpels. The flowers would then open up at daytime, but close up at nighttime.
Once the flowers of the northern dewberry are fertilized, drupes soon grow and replace each flower. The drupes are a dark-purplish color and range from ½ inch to one inch in diameter. Once the fruit has fully ripened it has a tart-sweet flavor.
Distribution and habitat
Rubus flagellaris is native to the central and eastern United States (from Texas, Oklahoma, Kansas, and Nebraska to the Gulf and East Coasts and the Great Lakes region), eastern Canada (Ontario, Quebec, New Brunswick, and Nova Scotia) and northern Mexico (Coahuila, Hidalgo, Nuevo León, San Luis Potosí, Sonora).
Rubus flagellaris' grows on dry soils, bogs, soft soils and wooded soils. This species is actually especially adapted to coarse textured soils (such as sandy soils), fine textured soils (such as loamy soils) and medium textured soils (such as clay-textured soils). R. flagellaris grows in a wide range of habitats including mesic to dry savannas and sandy savannas, abandoned fields, meadows in wooded areas, and woodland borders.
Rubus flagellaris' is adapted to a precipitation zone that ranges from 15 to 40 inches/year, tolerates soils ranging from 5.0 to 7.0 pH, and can survive temperatures as low as -23 °F. This species has a low tolerance to drought conditions and an intermediate shade tolerance, when compared to other species with similar growth habits in its natural regions. The plant has no salinity tolerance.
Many animals such as raccoons, fox squirrels, eastern chipmunks, white-footed mice, and other mammals eat the northern dewberry's fruits, and aid in the dispersal of the shrub.
When occasional wildfires burn down tall woody trees surrounding Rubus flagellaris, the resulting burning has a positive effect on population growth for the species. Other research has also shown that occasional wildfires are beneficial to the population's growth. The plant has a high tolerance to hedging from livestock or wildlife browsing.
The flowers of Rubus flagellaris, with a fragrant nectar, are excellent at attracting a large number of native bees. They also providing nesting materials and structures for the native bees. Some of the bee species that interact with the plant and pollinate the flowers are mason bees (of the genus Osmia), leaf-cutting bees, cuckoo bees (of the subfamily Nomadine), and miner bees.
Other insects that interact with the northern dewberry to help pollinate it are Siphonopora rubi (blackberry aphid), Metallus rubi (blackberry leafminer), Agrilus ruficollis (red-necked cane borer), and Edwardsiana rosae (rose leafhopper).
- The Plant List, Rubus flagellaris Willd.
- Natural Resources Conservation Service. "Rubus flagellaris Willd. − northern dewberry". Plants Database. United States Department of Agriculture (USDA). Retrieved April 29, 2015.
- Hilty, John. "Common Dewberry". Wildflowers of Illinois in Savannas & Thickets. Retrieved April 29, 2012.
- Flora of North America, Rubus flagellaris Willdenow, 1809. Northern dewberry, ronce à flagelles
- Seiler, John; Jensen, Edward; Niemiera, Alex; Peterson, John (2011). "dewberry Rosaceae Rubus flagellaris Willd.". Virginia Tech Department of Forest Resources and Environmental Conservation. Retrieved April 30, 2012.
- "Family Rosaceae Rubus flagellaris Willd". Robert W. Freckmann Herbarium. Retrieved April 30, 2012.
- >"Rubus flagellaris - Willd.". Plants for a Future. Retrieved April 30, 2012.
- Biota of North America Program 2014 county distribution map
- Taft, John B. (December 2005). "Fire Effects on Structure, Composition, and Diversity in a South-Central Illinois Flatwoods Remnant". Castanea. 70 (4): 298–313. doi:10.2179/0008-7475(2005)070[0298:FEOSCA]2.0.CO;2. ISSN 0008-7475. JSTOR 4034296.
- ‘’Lary Bird Johnson Wildflower Center’’, Rubus flagellaris Willd, April 30, 2012
- Grundel, Ralph; Pavlovic, Noel B.; Sulzman, Christina L (2000). "Nectar plant selection by the Karner blue butterfly (Lycaeides melissa samuelis) at the Indiana Dunes National Lakeshore". The American Midland Naturalist. 144 (1): 1–10. doi:10.1674/0003-0031(2000)144[0001:NPSBTK]2.0.CO;2. ISSN 0003-0031. JSTOR 3083005.
- United States Department of Agriculture Plants Profile for Rubus flagellaris (northern dewberry)
- Lady Bird Johnson Wildflower Center, University of Texas, Native Plant Information Network−NPIN: Rubus flagellaris (Northern dewberry) — Special value to native pollinators info.
- photo of herbarium specimen collected in Nuevo León in 1994