Location: Exotic and Invasive Weeds Research
Title: Seed polymorphism in two western Nevada Indian ricegrass communities Authors
Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 4, 2008
Publication Date: February 8, 2009
Citation: Ezzell, R.M., Clements, C.D., Harmon, D.N., Weltz, M.A. 2009. Seed Polymorphism in two Western Nevada Indian Ricegrass Communities [abstract]. Society for Range Management, Albuquerque, New Mexico, February 8-12, 2009. 62:32. Technical Abstract: Indian ricegrass (Achnatherum hymenoides) is a dominant perennial grass species in salt desert communities and lower elevations of the sagebrush (Artemisia) vegetation zone of western North America. This perennial bunchgrass reaches its heaviest densities on sandy soils and is an important winter forage species for domestic livestock. Seeds of Indian ricegrass are well reported to be highly polymorphic in the literature, yet little is reported on whether all or most plants actually produce all these polymorphic forms or do individual plants produce specific forms. For my high school internship I have investigated the polymorphic seed make up of individual Indian ricegrass seeds at two locations in western Nevada. Ten individual Indian ricegrass plants were randomly collected from the two separate sites and separated by polymorphic categories 1) large black, 2) small black, 3) brown, and 4) tan. The Flanigan site selection yielded an average of 694 seeds/plant with a range of 35-2,457. Brown seeds made up the majority of the seed types, 50%, while the tan seeds made up the least at 7%. The Empire site selection averaged 2,001 seeds/plant with a range of 210-4,544. Again, the brown seeds made up the majority of the seed type, 39%, but were more closely followed by large black, 31%, and small black, 27%. Tan seeds were again the lowest represented seed type at 3%. The average plant weight at Flanigan was 6.9 g and 15.9 g at Empire. The average seed weight was 1) large black = 0.0031 and 0.0034, 2) small black = 0.0016 and 0.0015, 3) brown = 0.00081 and 0.00093, and 4) tan = 0.00087 and 0.00061 g for Flanigan and Empire sites, respectfully.