Cheatgrass Response to Simulated Grazing

Authors: Clements, Darin - Charlie; Young, James; Harmon, Daniel - Dan

Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/15/2007
Publication Date: 2/1/2008
Citation: Clements, D.D., Young, J.A., Harmon, D.N. 2008. Cheatgrass Response to Simulated Grazing [abstract]. Society for Range Management National Meeting. Louisville, Kentucky.

Interpretive Summary:

Technical Abstract: At the very time of this writing we are looking out at a plume of smoke from a cheatgrass (Bromus tectorum) fueled wildfire. These cheatgrass fueled wildfires are an annual event here in Nevada as well as other arid western states, and thus the topic seems fitting to write about. This annual burning of rangelands has become most frustrating to resource managers, livestock operators, recreationalists and others whom enjoy the outdoors. Cheatgrass is annual grass that was accidentally introduced into Nevada in the early 1900’s. Cheatgrass is an early maturing grass that provides a fine textured fuel that increases the chance, rate, and spread of wildfires. Researchers have in the past and are currently investigating whether increased herbivory by livestock can reduce fuel loads and decrease the current wildfire cycles and allow succession to take place. We investigated the response of cheatgrass to different levels of simulated grazing to see if cheatgrass responded negatively or positively to different grazing levels. Cheatgrass seed collected from salt desert, Wyoming big sagebrush (Artemisia tridentata ssp. Wyomingensis), and mountain big sagebrush (Artemisia tridentata ssp. vaseyana) communities was stratified at 5ºC and planted into individual pots and replicated 6 times. Planting took place the first week in March and all plantings sprouted by the second week in March. Simulated grazing took place on the 1st of May by clipping the plants at 30, 60, and 90% levels. Controls, 0% clipping, was also replicated 6 times for each site as well. We recorded Dry Weight, Tiller Production, Spikelets, Seed Production, and Height. Prelimary results suggest that cheatgrass plants that received simulated grazing had an increase in spikelets and seed production. For example, 0% grazing averaged 63 spikelets per plant and yielded an average of 175 seeds per plant, whereas 90% grazing averaged 92 spikelets and yielded an average of 306 seeds per plant. Cheatgrass collected from salt desert shrub and Wyoming big sagebrush communities flowered and went to seed earlier significantly earlier than the mountain big sagebrush cheatgrass collections also. When looking at grazing to reduce fuel loads resource managers should be aware of the vigorous ability of cheatgrass to respond to such management.