Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Natural Resources


Paul F. McCawley


The original purpose of this study was to examine the influences of ecological site, seeding method and planting season on rangeland seeding success within the Tooele Fire Rehabilitation Project (TFRP) in northwestern Utah. The major objective of the TFRP, designed by the USDI Bureau of Land Management, was to establish a permanent cover of 'Nordan' crested wheatgrass (Aqropyron desertorum (Fischer ex Link) Schultes), 'Luna' pubescent wheat grass (Thinopyrum intermedium ssp. barbulatum (Schur) Barkw. and D. R. Dewey) and 'Al kar' tall wheatqrass (Thinopyrum ponticum (Podp.) Barkw. and D. R. Dewey) on approximately 20,000 ha of rangeland burned by a wildfire in July 1983. Thirteen combinations of site, method and planting season were identified within the study area; each was treated as an experimental unit. There were no significant differences (Pi0.05) in seedling densities between these treatment combinations. Means ranged from O to 1.9 seedlings/m2. There was significant variation (Pi0.05) among seedling densities within each treatment combination. Because of low seedling densities and non-uniform seedling establishment patterns, seedings within the study area were failures. Study effort was redirected to identify the causes of seeding failure. viii Among planting seasons and seeding methods, spring plantings and broadcast seeding contributed to failure. Most sites within the study area were suitable for seeding, with the exception of desert shallow loam. This site should not have been seeded because of steep topography and shallow soil. Planting during spring, broadcast seeding and the seeding of low potential sites explained only localized failure, however. The absence of crested wheatgrass seedlings within the study area was a major factor contributing to failure. Only two crested wheatgrass plants were found on a total of 195 permanently established transects. Of the three species seeded, crested wheatgrass was the best adapted to site conditions. Seeding technique was considered the most important factor causing failure. Contract workers on the project had no rangeland seeding experience. Drills were not properly equipped to control seed placement at the proper soil depth. Seeding was done during periods when site conditions were unfavorable. There was no evidence suggesting weather, grasshopper damage or cheatgrass competition caused failure.