Round-leaved sundew is an insectivorous, short-lived perennial forb
arising from a basal rosette of leaves. The upper surface of the leaf
blades are covered with reddish, glandular hairs tipped with a sticky,
glutinous secretion that traps insects. The inflorescence is a
one-sided raceme with 2 to 15 flowers on a scape that is 2 to 10 inches
(5-25 cm) long. There may be one to seven inflorescences per rosette.
The fruits are capsules with numerous small seeds [8,20,21,41,44].
The root system of round-leaved sundew is usually shallow (less than 2.4
inches [6 cm]) . It consists of a taproot - functional for less than
a year - which is replaced by mostly horizontal adventitious roots with
a few root hairs [8,37,50].
Round-leaved sundew compensates for the low available nutrients in its
habitat by catching and digesting insects [8,45,49,54]. Insects are
caught with the sticky glandular leaf hairs, and the leaf then folds
around the prey. The hairs secrete proteolytic enzymes which digest the
insect and enable the plant to absorb nutrients through its leaves
[37,45,52]. Insect capture is generally believed to enhance growth and
reproduction of round-leaved sundew [8,24,29,46,56]. It is
significantly correlated (p less than 0.01) with total leaf number, number of new
leaves formed, and total leaf area . However, Stewart 
determined that round-leaved sundew did not benefit from insect capture
in field experiments in the Jefferson National Forest, Virginia. The
benefits of insectivory may be site-dependent; round-leaved sundew may
benefit most from insect capture on the most nutrient-poor sites.
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- 8. Crowder, A. A.; Pearcon, M. C.; Grubb, P. J.; Langlois, P. H. 1990. Biological flora of the British Isles: No. 167. Drosera L. Journal of Ecology. 78: 233-267. 
- 20. Hickman, James C., ed. 1993. The Jepson manual: Higher plants of California. Berkeley, CA: University of California Press. 1400 p. 
- 24. Johnson, Charles W. 1985. Bogs of the Northeast. Hanover, NH: University Press of New England. 269 p. 
- 29. Krafft, Cairn C.; Handel, Steven N. 1991. The role of carnivory in the growth and reproduction of Drosera filiformis and D. rotundifolia. Bulletin of the Torrey Botanical Club. 118(1): 12-19. 
- 37. Lloyd, F. E. 1942. The carnivorous plants. Waltham, MA: Chronica Botanica Company. 352 p. 
- 41. Munz, Philip A. 1973. A California flora and supplement. Berkeley, CA: University of California Press. 1905 p. 
- 44. Roland, A. E.; Smith, E. C. 1969. The flora of Nova Scotia. Halifax, NS: Nova Scotia Museum. 746 p. 
- 45. Schnell, Donald E. 1976. Carnivorous plants of the United States and Canada. Winston-Salem, NC: John F. Blair. 125 p. 
- 46. Schulze, W.; Schulze, E.-D. 1990. Insect capture and growth of the insectivorous Drosera rotundifolia L. Oecologia. 82(3): 427-429. 
- 49. Stevens, Michelle. 1990. Between land & water: The wetlands of Idaho. Nongame Wildlife Leaflet No. 9. Boise, ID: Idaho Department of Fish and Game, Nongame and Endangered Wildlife Program. 11 p. 
- 50. Stewart, C. Neal, Jr.; Nilsen, Erik T. 1992. Drosera rotundifolia growth and nutrition in a natural population with special reference to the significance of insectivory. Canadian Journal of Botany. 70: 1409-1416. 
- 52. Swales, Dorothy E. 1975. An unusual habitat for Drosera rotundifolia L., its over-wintering state, and vegetative reproduction. Canadian Field-Naturalist. 89(2): 143-147. 
- 54. Tangley, Laura. 1984. Taking stock of white cedar wetlands. BioScience. 34(11): 682-684. 
- 56. Thum, Martin. 1989. The significance of carnivory for the fitness of Drosera in its natural habitat. 2. The amount of captured prey and its effect on Drosera intermedia and Drosera rotundifolia. Oecologia. 81: 401-411. 
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