OUR FINDINGS
Use the "Categories" list to search our library of 35 Findings.
The variability we continue to see in our lab results has thrown a great big monkey wrench into our ability to assess progress using only our lab results. However, we can still assess the progress our growers have made in increasing their use of tried-and-true soil health practices, including:
0 Comments
We have 5 years of data on the 51 sites which have been in the project since the very beginning, with data on both their management practices as well as their soil testing results. The average Days of Living Cover on these 51 sites has increased by 20 days since 2019. Our growers have increased their Days of Living Cover by increasing their use of cover crops, converting annual crops to perennial systems, and incorporating more fall-planted small grains into their rotations.
Our growers have increased their days of cover crops on average by 25 days/site since 2019. We examined the 200 sites for which we have cover crop data and found that our growers’ Cover Crop Use has increased for almost all our crop categories including Commercial Veg/Flower/Fruit, Commodity Row Crops, and Home Gardens.
Two thirds of all our growers have planted cover crops in the last 5 years, with Commercial Vegetable and Commodity growers leading the way. Only when a rancher inter-seeds a cover into an existing pasture or reseeds an annual field into a perennial crop do we credit a cover crop to that site, so we expect that cover crop use would be low for many of our established Perennial Hay/Alfalfa/Pasture sites. Dryland grain sites, which depend on 420 days of fallow soil to store enough soil moisture for a biennial small grain crop, avoid cover crops because cover crops can deplete soil moisture.
When we examine just the 51 sites for which we have 5 years of data, we see that our growers have decreased their Tillage Intensity by 17 points over the last 5 years. This is very good news since lower tillage intensity is correlated with better soil health. We use a Natural Resources Conservation Service soil erosion model to assign a soil disturbance score to all farm operations that compact or disturb soil. For example, NRCS assigns a single pass with a subsoiler-chisel plow a score of 52.6, a disc harrow gets a score of 11.67, and hay cutting equipment gets a score of 0.15. We total all the scores from each implement used in a field in a calendar year to compute the tillage intensity score for each site.
When we examine the Tillage Intensity of the 191 sites for which we have tillage data and group them into their 5 crop categories, we see that 4 crop groups have made very good progress in reducing their Tillage Intensity, with Commercial Veg/Flower/Fruit sites and Dryland Grains making the most progress. Perennial Hay/Alfalfa/Pastures have held steady with quite low Tillage Intensity scores. Home gardens also have low tillage intensity scores, because many of our home gardeners use mostly hand tools, which disturb the soil less and have lower intensity scores.
A majority of all our growers have used organic matter inputs (manure, compost, mulches) on their sites in the last 5 years, with home gardeners leading the way. We only count the organic matter inputs which are acquired off-site in this analysis. Manure deposited by grazing animals on-site, or clippings from on-site cover crops, are not counted as organic matter inputs here. Thus, perennial fields with aftermath grazing often appear to have no organic matter inputs, even though they may have many days of grazing animals depositing manure and urine there.
Organic Matter Input use has decreased by 13T/acre on average since 2019. When we examine our successive years of data and divide our sites into their different crop categories, we see that only home gardeners have increased their Organic Matter Inputs in the last 5 years. All other crop categories have seen a sharp decrease in Organic Matter Inputs. Commercial Veg/Flower/Fruit growers have seen the biggest decrease. Our growers identified several possible causes for this decrease.
|
AuthorElizabeth Black is the producer of the Citizen Science Soil Health Project Archives
March 2024
Categories
All
|