2010 Annual Report
1a.Objectives (from AD-416)
Determine optimal technique and irrigation protocol for the establishment of native plant species on a site that was formerly used for irrigated agriculture.
1b.Approach (from AD-416)
At Rosaschi Ranch, on the East Walker River, we will use experiments to determine optimal restoration protocols for restoring sagebrush shrublands on formerly irrigated fields. The design will compare levels of irrigation, mulching, and alternative seed mixes, incorporating two levels of functional diversity. Irrigation will be the main plot factor, and the mulching X seeding treatment will be the split plot factor. There will be 5 replications of each treatment combination. Ten separate study plots, 1.5 acres in size, will be established. Five will be irrigated and 5 will serve as controls for the irrigation treatment. Each study plot will be subdivided into seeding/mulching treatments in a split plot design with two levels of mulching (mulch, control) and two levels of seeding (high diversity, low diversity). Soil moisture monitoring will determine the extent of irrigation, which will take place as needed (depending on precipitation patterns) in the early part of each growing season. Research plots will be installed in 2008 and 2009 and irrigated in 2009 and 2010. Data collection will continue through 2012. Density plots will be established at random intervals along transects in each experimental block, and emergence and survival of seeded species will be response variables. Documents Reimbursable with Fish & Wildlife (USFWS). Log 36889. Formerly 5325-11220-005-10R (4/09).
Techniques for the revegetation of former agricultural lands will become more important as water rights are transferred from agriculture to other uses in the arid western U.S. The US Forest Service has acquired property with abandoned fields at Rosaschi Ranch on the East Walker River in the southern Great Basin. We are conducting factorial experiments testing the roles of (1) first-year irrigation, (2) seed mix functional diversity, and (3) alternative site preparation techniques in the establishment of native species and prevention of invasive species dominance on these abandoned agricultural fields. The experiments are taking place over two years, and data collection will occur during years two through four of the project. Subsequently, a full-scale restoration plan for Rosaschi Ranch will be completed, incorporating applied research to maximize restoration success.
During this fiscal year, we have implemented the second year’s restoration treatments at Rosaschi Ranch. Working with the USDA-NRCS Great Basin Plant Materials Center, we seeded 10 2.5 acre experimental plots with two seeding treatments. Half of each plot was then mulched and crimped. We installed a big gun sprinkler irrigation system and have been watering half of our 2009 experimental plots weekly and ¼ of our 2008 plots every other week.
We have set up gypsum block soil moisture sensors throughout the experimental design and are collecting soil moisture and temperature data using dataloggers. We also collect gravimetric soil moisture data. We have collected cover, density and biomass data on 640 subplots. We have organized and conducted meetings with the partners: NRCS, USFS, USFWS, and ARS. We have also led tours for USFWS, ARS, and USFS personnel.