In the Field: Wetland & Riparian Monitoring around the Modoc Plateau

By Denali Lowder, Adam Hoeft, Nick Shaw, Mike Heine, and the rest of the AIM team  

Welcome to In the Field, a blog series where we follow the work of CNPS Vegetation and Rare Plant program teams across the state.

When people imagine the Great Basin of Northern California, they may picture a huge emptiness, yet it’s full of life, sensitive habitats, and the plant and animal species endemic to the region. This past year, CNPS Vegetation Program staff spent the field season in the high desert of the Great Basin in Northern California and far northwestern Nevada, wrapping up our third year collecting data using the Assessment, Inventory, and Monitoring (AIM) protocol in wetland and riparian areas. The area is often the focus of proposed large-scale public land projects and livestock grazing, and the data we collect helps to restore and conserve important habitats.  

The Bureau of Land Management (BLM) piloted the AIM protocol specific to wetland areas in 2021 and officially established it in 2022. The project monitors and assesses wetland and riparian areas on BLM land from as far south as the Mexico border up to the Oregon border and beyond.  

Surveying, collecting, and enjoying the BLM lands

The BLM is using the information we have collected for the past three years for both baseline data and long-term data needed for restoration projects in sensitive wetland and riparian areas. In Southern California, we often surveyed sites that had been colonized by invasive Tamarix, which are scheduled for removal by chainsaw crews. In the Argus Range in the western Mojave, we collected data in the dense Arroyo willow (Salix lasiolepis) thickets for restoring California towhee (Melozone crissalis) nesting sites and preventing more soil erosion from wild burro impacts. In Northern California, we spent the bulk of our time surveying wet meadow systems, including monitoring the impacts of grazing. Overuse of sensitive wetland habitats has the potential to impact ecosystem function and biological diversity. Wetlands and meadows serve as a natural reservoir for water, capturing and storing snowmelt or rainwater. They help reduce downstream flooding and recharge aquifers during the wet season. These systems also capture and store carbon from the atmosphere, acting as natural air purifiers. The high plant diversity often found within these systems is an important food source for all the animals in the region. Given all the ecosystem functions that wetlands provide, we need to better understand them so we can restore and enhance them.   

While the Great Basin of Northern California doesn’t often get much attention, CNPS botanists and ecologists love spending time in the remote corners of the Modoc Plateau. Learning even a few of the endemic sedges (Carex), buckwheats (Eriogonum), and the very diverse locoweed (Astragalus) species in the Great Basin, can create a great appreciation for the area.  

With an amazing ecology and an awesome crew of talented botanists, we were eager to wake up every day before the sun and get to work documenting the biodiversity, sampling water quality, and digging soil pits throughout the vast BLM lands. 

Working in this expansive landscape, we often found ourselves completely removed from pavement, potable water, toilets, and city amenities, so when we’d get to pass through a tiny town like Cedarville, it’s the most exciting thing to happen all day. To go to a small-town diner and enjoy a BLT felt like a rare treat.

Land Stewardship Needs 

In some riparian systems, the grazing of livestock, wild horses, and burros can remove plant biomass and seeds, which can impact vegetative growth and resilience. It isn’t uncommon to hike to a site in the Great Basin and spook a massive herd of horses grazing on the exact natural spring of wetland vegetation we are about to survey. In places like this, the collection of wetland data plays a significant role in monitoring and guiding the BLM in land stewardship strategies. 

Working on the CNPS field crew in northeastern California has been one of the great privileges of our early careers. Because we returned to many of the same 120 sites over the three-year project, we gained an intimate familiarity with the landscapes, as if we were in our own backyards. We collected data rain or shine, through muck and mud (a soil scientist will tell you these are not the same thing), and we had to get our truck un-stuck from three-foot deep mud countless times.  

It’s fascinating to see how sites can vary between years, and from season to season. Returning to a once-degraded site, and seeing that the restoration projects are working, gave us a real appreciation for the long-term monitoring data and land management efforts that BLM implemented. Seeing sites with issues related to soil erosion, invasive plants, or grazing allowed us to appreciate the effectiveness of stewardship efforts in maintaining these resilent wetland areas, and our monitoring work offers an accurate reflection for what management actions are working. Not many people get the chance to be part of large-scale beneficial changes of their favorite habitats, and being part of this work brings us enormous pride.

Mike Heine and Nick Shaw are lead field botanists for CNPS; Denali Lowder was a lead field botanist with CNPS in 2024. All worked in conjunction with the Colorado Natural Heritage Program and the BLM. Our AIM team loved surveying vegetation in the wilderness with no cell phone reception for many days at a time! 

Adam Hoeft is the field coordinator for this statewide BLM AIM riparian & wetland project. He has been a part of this project for all three years with CNPS and plans on being a part of future sampling seasons.