Regenerating Desertified Agricultural Land in Northern New Mexico

Reunity proposes to use a desertified one-acre piece of land as a test plot on which we will grow multiple varieties of locally adapted, drought-resistant crops using a variety of compost types. We will also test watering strategies, including dry-land techniques informed by local indigenous practices. While this plot of land was farmed for centuries by indigenous agriculturalists and Hispanic colonists and their descendants, it was most recently the site of a sand mining operation. We propose to experiment with different composts to increase SOM. We will focus on composts created in Johnson-Su Bioreactors, which are rich in fungal communities and show promise in substantially boosting agricultural yields. The efficacy of Johnson-Su compost is somewhat controversial, as to date no peer-reviewed research has been published, despite experiments undertaken at various sites with varying results. Several SARE projects are currently evaluating Johnson-Su bioreactor compost and other fungal inoculants (for example, FW20-371, which seeks to regenerate mountain meadow pastures in Colorado using Johnson-Su compost; GW21-224, which is evaluating fruit yields on a California dry farm using fungal inoculants; FW22-404, which involves an on-field trial of cover cropping and Johnson-Su inoculants.) No projects we are aware of (including those supported elsewhere) are testing the use of fungal inoculants on desertified soil in a low-water or dry-farming environment with drought-tolerant plants, an important experiment for New Mexican farmers.   

Objective #1 – Compare Plant Productivity Using Different Compost Inputs

Using a split plot design (modified to eliminate randomization, as the test plot is uniformly desertified; Altman and Krzywinski, 2015), test at least 8 types of compost mixes and delivery methods. For example: 1) conventional compost made with Reunity’s aerated static pile system, 2) Johnson-Su bioreactor compost, 3) vermicompost, 4) conventional plus Johnson-Su composts, 5) Johnson-Su compost and vermicompost, 6) biochar inoculated with Johnson-Su compost buried 2 feet below surface, 7) biochar inoculated with Johnson-Su compost buried 1 foot below surface, 8) Johnson-Su compost applied to soil surface. We will work with our technical advisor, Dr. Follingstad, to refine and implement this design. Dr. Follingstad will also work with us to design our soil testing and data collection protocols. Reunity currently tests soil and plant tissue 1x – 2x per year; the existing protocol may be modified for the test plot.

A variety of plants will be grown under the 8 or more composting conditions: commercial seeds currently grown at Reunity Farms will be compared to their drought-adapted heirloom counterparts. Heirloom and landrace (locally adapted) seeds, many of which are currently being grown at the adjacent Full Circle Farm, will be obtained from local indigenous communities and the Tesuque Farm seed bank (the largest indigenous seed bank in New Mexico, https://tesuquepueblofarm.weebly.com/about.html), or from Native Seed SEARCH, a non-profit based in Tucson which specializes in conserving heirloom seeds adapted to drought conditions. https://www.nativeseeds.org/

Objective #2 – Study/Determine Water Requirements

We will test how the above compost and plant species combinations perform in a variety of watering conditions: spot irrigation (as used at Reunity Farms), reduced irrigation (as used at Full Circle Farm), and dryland farming. The latter test will include designing test plots which make use of channeled summer monsoon rains, as well as traditional (e.g. cobble) and modern mulches and Zuni-style waffle gardens. Traditional Zuni farming makes use of rainfed fields and alluvial fans, designing check dams and other physical features to channel, capture, and retain water during intense monsoon rainfalls. As our summer monsoon is unpredictable, with intense rains that can be destructive, experimenting with indigenous water harvesting techniques is an important experiment.   

Emily Arasim, a native of Tesuque Pueblo, said of her community’s heirloom seeds and the rapidly changing climate: "We have seeds that have been around for 6,000 years that have been cultivated generation by generation by our Pueblos that can handle these crazy summers we get. And that's going to be increasingly important for the whole world as we face these things." (Egolf-Romero 2017) Chemist and farmer Loretta Sandoval of Dixon, NM tested landraces versus hybrid peppers on her farm, and noted their ability to break dormancy and germinate more quickly than hybrids. This is critical for survival in a desert climate in which the summer monsoon season is relatively short; in New Mexico it usually starts in late June. It has been noted that Zuni traditional farmers hold off planting certain species until it rains, which gives these crops a short time to mature; we will observe germination times in our test plots.  Sandoval noted the landraces’ drought resistance: “Last summer, which was the hottest recorded New Mexico summer in history, I went seven weeks without watering my landraces and they were fine… they weren’t even wilting, and it was over 100 degrees every day.” (Egolf-Romero 2017).  We expect our findings will mirror Sandoval’s – that is, modern plant varieties will be more productive in ideal conditions (i.e. with irrigation), but traditional plants will prove to be more resilient and productive in the drier and unpredictable conditions that better represent the future of agriculture in the Southwest.   

Objective #3 – Study Soil Health Metrics

Periodic testing of plant tissue and soil will be performed to determine the health of crops, which amendments to the soil are required, and the soil’s organic matter content. Baseline and subsequent periodic testing will determine how quickly organic matter can be increased in the desert soil, and how SOM levels affect the productivity of the plants we are testing. Unamended desert soil may contain about .5% carbon or less, and the maximum is ~10% in wetland and peat forest regions, so there is much potential for improving desertified soils and increasing its ability to sequester carbon. (MIT Climate Portal) As mentioned previously, Reunity Resources regularly performs seven soil and plant tests: water retention, water percolation, soil carbon, soil fungal to bacterial ratio, soil salinity, root-fruit-shoot biomass, and seed germination rates. Dr. Follingstad will work with Reunity staff to determine if additional types of tests may be needed, as well as determine optimal frequency of testing.