After a long year of too many virtual meetings, the Nevada Section – Society for Range Management (SRM) held its annual summer field tour June 10, 2021. The tour visited numerous sites near the northern Nevada town of Battle Mountain. It was good to see so many familiar faces in person again and to meet new folks interested in the art of range management.
This year’s tour theme was “Breaking the Cheatgrass Fire Cycle”. Far too often the battle against cheatgrass and its’ associated wildfires seems hopeless, therefor we wanted to focus on effective methods that can restore and protect the landscape. Attendees included local ranchers, employees from the Bureau of Land Management (BLM), USDA Agricultural Research Service (ARS), US Fish and Wildlife Service (USFWS), Nevada Division of Forestry (NDF), Nevada Department of Wildlife (NDOW), Nevada Association of Conservation Districts (NVACD), scientists from the University of Nevada, Reno (UNR) and others interested in successfully managing cheatgrass and reducing wildfires.
We began the day by meeting at the Horseshoe Ranch where Dave Voth, ranch manager and Chris Jasmine, Manager of Biodiversity and Rangelands for Nevada Gold Mines (NGM), gave us an overview of NGM’s ranching and rangeland conservation operations. Nevada Gold Mines, a joint venture between Barrick Gold and Newmont Mining, manages and leases numerous ranching properties. It also is an active participant in both Nevada’s Conservation Credit System and Barrick’s Bank Enabling Agreement, which address impacts to Greater Sage Grouse habitat. Nevada Gold Mines ranches, including lessees, prioritize a commitment to conservation, including improvements to the habitat over time. They work closely with NDOW and USFWS on projects to improve the landscape and reduce threats from wildfires.
Our first stop was a section of the Horseshoe Ranch allotment that has been included in the BLM Outcome Based Grazing Authorizations Initiative (OBGA). This new BLM initiative creates flexibility that is needed to best manage grazing on a highly variable landscape. One emphasis of this program is to create and maintain fuel breaks with grazing to disrupt fuel continuity (Figure 1, click on image to see larger). As Dave Voth explained, this requires flexibility in the allowed number of cattle and options to move the animals depending on the annual production of cheatgrass and perennial forage. Dave said the goal is to reduce the cheatgrass residual dry matter along the roadways, creating a firebreak that could limit the intensity and magnitude of future wildfires. He emphasized the importance of good monitoring to ensure that fuels are being reduced with minimal negative impacts to the desirable plant community. The area we observed had virtually no perennial plants and was dominated by cheatgrass and other weeds. Such areas are ideal for targeted grazing fuel breaks because they pose little risk for overutilization of desirable plants. The group discussed how monitoring would require a “control” area without any grazing to determine the effectiveness of fuels reductions, and how a major difficulty is achieving the BLM stubble height requirement with a plant like cheatgrass. The comparisons of grazed versus not grazed must be made within the same year, as opposed to having a baseline first year measurement and then comparing year to year, because annual cheatgrass production is so variable. Dave expressed the responsibility he feels for this effort to succeed since the ranch is at the forefront of this new program (OBGA) and it could be the difference between the program expanding or not.
One of the attendees asked if targeted spring grazing of the cheatgrass could control cheatgrass enough to allow seeding of perennial grasses to be successful. Chris Jasmine explained that the goal was not to control the cheatgrass but to reduce its biomass (fuel) production. He stated that even with targeted grazing , cheatgrass produces enough seed to ensure its establishment the following year, and competition from the cheatgrass would decrease seeded perennial grass success. Targeted grazing can buy time and decrease the chance, rate,spread and season of wildfires until we can implement a more effective cheatgrass seed production control means and establish a sustainable perennial plant community.
Our next stop was a 1,000 plus acre herbicide application on the TS Ranch (NGM property). The group could see the striking effectiveness on the treatment area, where practically no cheatgrass was growing. The sparse perennial grasses, such as basin wildrye and western wheatgrass, stood out dramatically in the absence of cheatgrass. Pre-emergent herbicides do not affect established perennial plants, with their deeper root system extending below the very shallow layer of active herbicide (<2”). William Kutosky with USFWS in the Partners for Fish and Wildlife program explained about the process of using pre-emergent herbicides to control cheatgrass (Figure 2).
William often partners with NGM on habitat improvement projects. He explained how soil active pre-emergent herbicides, such as Imazapic (Plateau), will remain active in the soil and be taken up by the roots of all newly germinated plants, effectively killing them for one growing season, while having no effect on the existing established perennials with deeper roots below the shallow (<2”) herbicide soil zone. Imazapic should be applied (6 oz product/acre) in September to preempt any fall (October) cheatgrass germination, which can often occur. William explained that by doing so the cheatgrass seedbank will be depleted when the cheatgrass seed germinates, and then the seedlings die before any new seed is produced.
The goal of using pre-emergent herbicides, such as Imazapic, is not to control cheatgrass long- term,which it is incapable of doing; it will only kill cheatgrass as long it is active in the soil (about 12-15 months) – but to deplete the cheatgrass seed bank so there is a window of opportunity to seed perennial grasses without cheatgrass competition. The perennial grasses will suppress cheatgrass and decrease fire threats long-term. The timeline for this process is to apply the herbicide in September, fallow the site for 1-year (depleting the cheatgrass seed bank) and then seed perennial plants in October, – 1-year after the herbicide application. This ensures your seeded perennials are safe from the herbicide activity and have the maximum available soil resources in the absence of cheatgrass competition. Imazapic can typically be applied for under $20 per acre. On the opposite side of the road was a 20 plus year-old seeding dominated by ‘Immigrant’ forage kochia. This seeding effort was conducted in 1991-92 to protect the critical Area 6 mule deer winter range. This provided a good opportunity to discuss the long-term sustainability of a successful green strip. Charlie Clements, range scientist with ARS, was part of this seeding project. He explained that they used spring discing to kill the cheatgrass prior to seed production, in order to reduce the cheatgrass seed bank prior to seeding perennials. They were quite successful establishing bluebunch wheatgrass, crested wheatgrass and ‘Immigrant’ forage kochia. Over time, however, the green strip was highly preferred by animals with little perennial forage in the untreated areas. With heavier utilization the perennial grasses were lost leaving forage kochia to dominate. Even though forage kochia is not effective at suppressing cheatgrass like a perennial grass (tap root versus fibrous root), the space that kochia occupies reduces opportunities for cheatgrass, which was evident from observing how the untreated areas without forage kochia were dominated by dense cheatgrass cover. Charlie showed how the green leaves of forage kochia hold a lot of moisture (crush them in your hand) throughout the fire season and are very effective at stopping or reducing fire intensity.
Lesley Morris, rangeland ecologist with UNR, asked if what we were looking at – a dense stand dominated by forage kochia – was the goal. The group came to a consensus that there are many goals with rangeland rehabilitation efforts, and if this goal was to reduce fuels and fire threats, then yes, the goal was achieved. If the goal was to provide a diversity of native plants representative of historical times before cheatgrass, then no. However, the latter was not the goal in this effort. The group further discussed that ultimately we all have the same broad goal of improving habitats, and if we could magically wish plants back on the ground, we would choose a diverse plant community of native grasses, shrubs and forbs. However, these are very arid, highly variable ecosystems often receiving less than 8 inches of annual precipitation, mostly during winter months. If we want to establish perennial plants that provide a service, we often have to narrow our focus and use introduced plants such as forage kochia and the crested wheatgrasses that have the inherent potential to be adapted to such sites. Caleb McAdoo, Eastern Region Habitat Supervisor for NDOW, stressed the important service these green strips of forage kochia provide. While he would like to see a more diverse plant community to provide a greater diversity of use for wildlife, he understands that sometimes these kochia stands may be the only food source available to help animals survive. Also, the fire protection they provide, to stop fires from spreading into intact diverse native plant communities that the wildlife rely on, is of utmost importance.
The next treatment area was a successful seeding of perennial grass that is part of Chris Jasmine’s ongoing efforts for NGM (Figure 3 below). Each year Chris applies pre-emergent herbicide to a cheatgrass dominated area (~1,000 acres), the most recent being our last field stop, and then also seeds the previous year’s cheatgrass herbicide fallow plot. This repeated effort allows him to determine the methods that work best and what is a realistic chance of success. Because of the arid and unpredictable environment we are working in Nevada, there will always be failures because the precipitation just isn’t there, like this year, for example. However, Chris is confident that with enough repeated efforts you can be successful at least 75% of the time, resulting in an astounding improvement to the landscape. He always follows the steps of a 1-year herbicide fallow, to reduce cheatgrass competition, and then seeding with 6 to 8 pounds per acre of Siberian wheatgrass. He can achieve success with this treatment for under $100 per acre ($16/acre fixed wing herbicide application + $75/acre for seed and drill seeding). The treated areas are private grazing lands where multiple use is not a strong component, and a single species seed mix is appropriate. Besides being economically preferred, Siberian wheatgrass is readily available in large quantities and can be established on very arid sites. By converting cheatgrass landscapes to perennial grass dominance, multiple benefits are achieved – from increased quantity and season of forage to suppressing cheatgrass, and decreasing fire risk, and these are even benefitting carbon storage, an important topic when considering CO2 emissions. Perennial grass stands are found to store much more carbon than annual grass communities.
After lunch at Lions Park in Battle Mountain we traveled about an hour north along Izzenhood Road to the mouth of Izzenhood Basin, where Marissa Murphy, project manager of range improvements and emergency stabilization and rehabilitation (ESR) with BLM’s Elko district and Casey Addy, the district’s ESR manager showed us a recent successful seeding effort after the 2016 Hot Pot Fire (Figure 4, click on image to see larger). The Hot Pot Fire burned 122,000 acres over five grazing allotments. Marissa explained the importance of having an effective seeding effort because Izzenhood Basin and the surrounding upper elevations are critical wildlife use areas. She emphasized the importance of choosing an effective seed mix based on experience. ESR plans must be completed 21 days after the fire. At that time post-fire funding for up to 5 years can be applied for, though Marissa and Casey explained that there is a national cap of $26 million per year and they have to compete with all BLM offices for those funds. They have been quite successful procuring funding, a testimony to their strong ESR program in the Elko district.
Marissa explained that seeding done at the appropriate rates and timing, using the best methods available, can significantly increase your chance of success. The Elko BLM district has a great working collaboration with NDOW that helps meet everyone’s needs and improves success by sharing the seed purchasing and application contracting efforts to keep projects on time. It is critical to establish plants after the fire because often very few resources are left, and wildlife will be reliant on the plants you establish from the seeding effort as well as forage for the grazing allotments. At this site, because of the topography and to avoid disturbing post-fire resprouting perennial plants, broadcast seeding was used instead of the preferred drill seeding method.
One plant that established very well from the broadcast seeding was ‘Snowstorm’ forage kochia. ‘Snowstorm’ is a taller structured cultivar than ‘Immigrant’ forage kochia. This is an important characteristic to provide a food source that remains above the snow in the winter months. It resembles sagebrush from afar with its silvery gray leaves. Travis Allen, game biologist with NDOW, explained how important the fast establishment of ‘Snowstorm’ forage kochia is (sometimes 3 feet tall the first season) to provide cover and forage for the wintering mule deer herd. He explained that 2,000 to 4,000 deer winter in the area, and having food and cover is critical to their survival. Until the slower establishing sagebrush can reach that size (>3 feet), ‘Snowstorm’ forage kochia can provide that much needed resource. Forage kochia can also provide a good source of browse that takes utilization pressure off sagebrush to ensure its establishment and survival in the first few years. As Travis said, the kochia and sagebrush are living together very happily.
Casey Addy then discussed their proactive seeding efforts. Often we focus on reactive seeding efforts after a fire, but Casey explained how the BLM is focusing on proactive green strip seeding efforts to protect their successful fire rehabilitation seedings, as we saw at Izzenhood Basin, from future fires. He led efforts to seed a 1,500-acre green strip along Izzenhood Road, (16 miles, 800 feet on both sides of the road) in 2020. Multiple sections of green strips have been seeded over the years along this road because the valley is at high risk for fire and has burned multiple times.
The green strips are intended to stop the fire from spreading into the intact upper elevation ranges that surround the valley and are home to large herds of deer. The lower elevations are not easy places to establish plants, and unfortunately 2021 was a very dry year. The green strip seeding area was herbicide fallowed in 2020 to reduce the cheatgrass seed bank and should allow the area to be reseeded this fall hopefully with more precipitation and still low competition next year. Casey explained that unless the perennial green strip species (Siberian wheatgrass and forage kochia) establish at a density high enough to suppress cheatgrass fuels, the goal of protecting their fire rehab seeding at Izzenhood Basin is not achieved, and they must reseed to achieve that goal and justify the cost of the herbicide control efforts prior to seeding. Casey also brought us full circle, discussing when to rest from grazing and when not to rest after seeding or fire disturbance. If a significant amount of perennials survived the fire and are stressed, or you have established seedlings from a seeding, those plants need to be rested from grazing until they have recovered or matured, which could take years. If the seeding failed or minimal perennial plants are present after the fire, and cheatgrass dominates, it is best to graze the cheatgrass to reduce fuels. A frequent logistical issue after a fire is that part of the area has remaining perennials and part does not; however, without fencing to separate the two parts, the entire area will be rested.
The final stop for the day was at a research exclosure now occupied by the USDA-ARS Great Basin Rangelands Research Unit (GBRRU), Range Rehabilitation Lab, led by Charlie Clements. The exclosure was originally built with funding from an Initiative for Future Agriculture and Food Systems (IFAFS) grant that supported over 30 scientists and numerous graduate students working on the site. That project began in 2001, and while many graduate degrees were produced, not many successful rehabilitation methods were developed as the exclosure was left a near monoculture of cheatgrass after the project. In 2014 after discussions with the Elko district BLM, the GBRRU began researching applied methods to rehabilitate the cheatgrass infestation in the exclosure. The USDA-ARS team of Charlie Clements and Dan Harmon began testing various herbicide applications and seed mixes in 2015. Their goal was to increase the success of establishing perennial grasses through seeding methodologies that will, in turn, actively suppress cheatgrass densities and associated fuels that are often the catalyst for catastrophic wildfires. One focus was to determine what weed control and annual precipitation conditions resulted in successful native grass establishment (Figure 5).
Using repeated treatments of seeding introduced grasses (Siberian wheatgrass 8 lbs./acre) and native seed mixes (bluebunch wheatgrass 6 lbs./acre, Sandberg bluegrass 2 lbs./acre, Sherman big bluegrass 2 lbs./acre) for comparison, they were able to determine how often native grasses could be established. Comparisons of weed control included Landmark XP (off market), Imazapic, broadleaf control (Telar and Milestone) and burning of cheatgrass.
Charlie walked the group through each year’s treatments and seed mixes and it was clear which were successful and which were not. Siberian wheatgrass established well in an 8 inch precipitation year with heavy mustard competition where the native grasses failed. With 13 inches of precipitation and effective cheatgrass herbicide control, Siberian wheatgrass and the native grasses established well. Seeded directly after a fire (usually has more cheatgrass competition than an herbicide fallow) with 13 inches of precipitation Siberian wheatgrass and Sandberg bluegrass established well while bluebunch wheatgrass failed from lack of resources. During a 12-inch precipitation year with ineffective weed control (too much competition) Siberian wheatgrass and the native grasses all failed, emphasizing the importance of effective weed control prior to seeding. In summary first and foremost, effective weed control is required for any perennial grass establishment, introduced or native. For the native grasses, greater than 8 inches of annual precipitation should occur for establishment. This site has received greater than 8 inches only 2 of the past 5 years making the use of native grasses risky but possible. Charlie also explained that timing is even more important than the total precipitation. Good late fall-winter precipitation that leads to earlier germination had the greatest success, likely due to the seeded perennial seedling roots having more time to grow before the dry summer months, when survival is limited.
The day wrapped up with open discussions of all the sites we visited. Everyone had a genuine interest in rangeland rehabilitation efforts that decrease wildfire threats and successfully manage the cheatgrass problem. No one wanted the conversation to end, there was a hopeful comradery among new and old friends. The group finally headed back to Battle Mountain almost 2 hours later than planned, with a feeling that we can be successful managing cheatgrass and breaking the large frequent fire cycles that have overwhelmed northern Nevada. The first step of making a positive change is the willingness to try, and we are confident the attendees will be trying a lot of the techniques they learned on the tour. The Nevada section of SRM would like to thank everyone for their participation this year (Figure 6).
By Dan Harmon and Charlie D. Clements