Author: Ryan Olson
Exotic species of other grasses and organisms are constantly invading rangelands across the globe. It sounds scary, right? Well, it is. Invasive species cause significant ecological and environmental impacts, affecting rangelands globally and changing ecosystem processes. How? Invasive species use a variety of mechanisms to outcompete native species, such as litter accumulation or novel thatch layer build-up. This is formed over time, compressing older litter into layers intertwined with decaying organic matter, living organisms, and portions of the topsoil horizon. This accumulation is a challenge for range managers.
In a brand new article in the Rangeland Ecology & Management Journal, being released in January, researchers from North Dakota State University at the Central Grasslands Research Extension Center in Streeter, North Dakota, tested different grazing management strategies when dealing with invasive species, such as bluegrass, including season-long grazing, rotational grazing with differing grazing intensities, and patch-burn grazing. In the study results, patch-burn grazing significantly reduced the thatch layer of invasive bluegrass. Researchers found that compared to idle pastures, specific management practices like patch-burn grazing can reduce thatch accumulation far more than other management practices. The researchers implicated that range managers should utilize these practices when working with thatch-producing grasses to minimize biomass accumulation and the impact of invasive grasses.
This research will create broad implications for range managers in the United States and globally, helping to reduce the challenge of managing tough, invasive grasses that harm ecosystems and producers' livelihoods. However, there is hope with specific management practices such as patch-burn grazing! I encourage you to read more in the Rangeland Ecology and Management Journal, Volume 98, January 2025, and find out what work is being done to mitigate invasive grass species in the United States and elsewhere.
Read more:
Kjaer, E. L., Limb, R., Geaumont, B., Harmon, J., Hovick, T., & Sedivec, K. (2025). Fire and grazing reduce invasive grass thatch in rangelands. Rangeland Ecology & Management, 98, 414–418.
Author: Kylie Hopkins
Advancements in the global positioning system (GPS) tracking and remote sensing technology have allowed Ranchers and Environmental managers to collect more precise, real-time data of their populations. A device called an Accelerometer aids in the data collection of natural resource and wildlife distributions, along with livestock habits and preferences. They are beneficial due to their ability to recognize certain behaviors that could indicate if their livestock have a welfare concern, display disease symptoms, or could be giving birth; referred to as parturition. With a faster way to collect data, ranchers can respond faster to concerns or incidents, which can significantly improve the livelihood of the animals being monitored.
Range managers have the opportunity to use these systems to get hourly data on Riparian water sources and vegetative grazing patterns to make more educated decisions to benefit the livestock and surrounding ecosystems. Ongoing work with internet-based software and mobile satellite technology has the potential to save ranchers time and money in monitoring their livestock. Implementing this technology would help to understand the social behaviors of range animals. Studies have shown cattle in the New Mexico desert region can spend 39-46% of their time grazing, while cattle in Germany can spend 54-67% of their time grazing and socializing. Understanding the data from monitoring these behaviors can improve decisions about habitation and predator conflicts. These strategies and technologies allow management teams to take care of wildlife and livestock in a cohesive way.
Source:
Bailey, D. W., Trotter, M. G., Tobin, C., & Thomas, M. G. (2021). Opportunities to Apply Precision Livestock Management on Rangelands. Frontiers in Sustainable Food Systems, 5, 611915.
Author: Carson Browder
Introduction
Rangeland wildfires within the Great Basin that result in the loss of core sagebrush habitat and displacement of native forbs, grasses, and shrubs have dramatically increased within the past 10 years. As high-severity wildfires continue to increase, the threat of invasive annual grasses such as Poaceae Bromus tectorum drives this increase in rangeland wildfires and shortens the historic mean fire interval return by serving as an extremely receptive and readily available early-season fine fuel source. Because of the aggressive and adaptable nature that cheatgrass has to disturbance events within rangelands, it often outcompetes native perennial grass species that have been displaced from their niches and lost to wildfire.
What is greenstripping?
In short, greenstripping is a fire management technique that involves planting fire-resistant vegetation in strategic areas to create natural fire breaks that slow or stop the spread of wildfires. These strips of vegetation not only reduce the intensity of fires but also protect critical infrastructure, wildlife habitats, and grazing lands. This practice started gaining attention after a test experiment in 1947 by Platt and Jackman was deemed highly successful.
But why Forage Kochia?
Due to the heavy losses of native shrubs from severe rangeland wildfires, Forage kochia (Kochia prostrata) has been introduced to the intermountain region as a hardy substitute for post-fire reseeding practices due to the low success rate of sagebrush reseeding projects. Forage kochia is a long-lived perennial half-shrub that thrives in the temperate, semiarid, and arid regions of Central Asia and the western United States. Forage kochia provides excellent forage for native wildlife such as mule deer and livestock alike, making it almost preferential to planting sagebrush. Not only is kochia a great source of forage for any grazing animals present on a rangeland, but it has been shown to effectively act as a fire break when used in tandem with greenstripping practices. It was found in an article written by Deane Harrison et Al in 2002 that forage kochia has 4 to 10 times the moisture content of crested wheatgrass (Agropyron cristatum), another commonly used species used in greenstripping practices. Additionally, forage kochia was observed to reduce general flame lengths which proves immensely helpful to firefighting resources attempting to suppress the fire (Harrison et Al, 2002).
Success, but downfalls?
Several case studies within the Great Basin demonstrate the efficacy of forage kochia in wildfire mitigation. In Mountain Home Idaho, large-scale greenstripping projects have successfully reduced fire sizes and protected critical sagebrush habitats. Similar initiatives in Βι¶ΉΣ³» and Utah have also shown promising results in preventing the spread of fire within a cheatgrass-dominated system. There is valid concern about forage kochia potentially becoming invasive to a sagebrush steppe community much like cheatgrass does. It is always worrisome to most when an introduced species becomes naturalized within a specific environment since introduced species can displace native species. I highly recommend reading both of the articles cited and featured below if this topic interests you!
References
B.L. Waldron, J.-S. Eun, D.R. ZoBell, K.C. Olson, Forage kochia (Kochia prostrata) for fall and winter grazing, Small Ruminant Research, Volume 91, Issue 1, 2010, Pages 47-55, ISSN 0921-4488, .
Harrison, R. Deane, et al. "Forage kochia helps fight range fires." Rangelands Archives 24.5 (2002): 3 7. .
Author: Zach Wells
Fire is a well-known and well-documented disturbance in rangeland ecosystems. However, with invasive species being more prevalent than ever, fire has become a critical event that can lead to extreme alteration of a site. Historically, an ecosystem had time to rebound from fire without competition from invasive species that thrive in a recently disturbed site. With today's invasive species, though, ecosystems can be heavily influenced after fire. These invasives influence a fire cycle that is more beneficial to them, thus further promoting their prosperity.
These arising problems require management to mitigate their effects. Targeted grazing has been a suggested tool to help manage fuel loads and invasive seed banks. It can also help maintain fire breaks as well. All of these possible use cases can help in controlling fire behavior and helping land managers fight off invasive species.
Concerns over targeted grazing have been raised. One of these concerns was a possible unintended consequence of cattle "re-seeding" the landscape with invasive seeds through their feces. But a new study "Evaluating the effects of ruminal incubation and abomasal enzymatic digestion on the germination potential of Bromus tectorum" indicates a nearly complete inhibition of cheatgrass germination after digestion in cattle (Holton et.al 2024). This is yet another step towards showing the great potential of the effectiveness of targeted grazing. The more tools land managers can utilize, the better our lands can be managed, both in terms of money and efficacy.
References: Email zwells@unr.edu.