Location: Great Basin Rangelands ResearchTitle: Common garden comparisons of reproductive, forage and weed suppression potential of rangeland rehabilitation grasses of the Great Basin
Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 9/22/2017
Publication Date: 1/27/2018
Citation: Harmon, D.N., Clements, D.D. 2018. Common garden comparisons of reproductive, forage and weed suppression potential of rangeland rehabilitation grasses of the Great Basin. Society for Range Management Meeting Abstracts. 71:275.
Interpretive Summary: Not applicable
Technical Abstract: Common garden experiments are a means to remove environmental effects. Using 8 species of perennial rangeland grasses, we established a common garden (3 reps x28 plants = 84 plants/species). We found that ‘Hycrest’ crested wheatgrass (Agropyron cristatum) and bluebunch wheatgrass (Pseudoroegneria spicata) produced the greatest amount of seed (6,117 and 4,4155/ plant) compared to other species such as Squirreltail (Elymus elymoides) (2,172/plant). Monthly, we randomly harvested one plant/rep to estimate biomass. We compared only the 5 mid-sized grasses excluding the large basin wild rye (Leymus cinereus), the small Sandberg bluegrass (Poa secunda) and the root creeping wild rye (Leymus triticoides). June biomass of crested wheatgrass was significantly larger than all other grasses except bluebunch wheatgrass which was similar. Comparing soil moisture we found only crested wheatgrass, bluebunch wheatgrass, and Basin wildrye consistently depleted soil moisture significantly from control plots (bare soil) (e.g. June soil 4-15cm depth; crested wheatgrass = 3.7%, Thurbers needlegrass (Achnatherum thurberianum) (= 8.95%% and control = 10.9%). Results on available soil nitrogen uptake were similar to soil moisture. The suppression of weeds like cheatgrass (Bromus tectorum) by perennial grasses is thought to occur by the perennial grass competing for and limiting available soil moisture and nitrogen to the annual cheatgrass. These results emphasize the importance of considering the potential of a species to achieve specific goals such as cheatgrass suppression and strengthen the concept of the introduced grass, crested wheatgrass, being an ecological equivalent, and functionally very similar to the native bluebunch wheatgrass.