Use of Wood Ash as Soil Amendment on Annual Rangelands

Use of Wood Ash as Soil Amendment on Annual Rangelands

Summary

This project is attempting to quantify benefits from the use of wood ash on rangeland. Five locations were chosen, representing soil diversity typical of Butte County (California). Plots were 50’ x 100’, with ash spread at two rates: 10 tons/acre and 20 tons/acre of wood ash. These were on opposite strips within the plot. Four exclusion cages were used on the treated areas; two per application rate, and one in non-treated adjacent area as a control (0 tons/acre) plot.

Sporadic, insufficient rainfall during the 2012 season prevented ash from filtering into the soil profile and produced so little forage that valid measurement was difficult. The project was extended one year (into 2013), which resulted in slightly better conditions.

Sampling will occur in May and June, 2013. Generally, the response to potassium was greatest, showing in positive legume growth, with moderate nitrogen and phosphorous response. Rainfall amounts and timing varied across the five locations and seem to be the most significant variables in test results.

Ideally, this study should proceed for several more years in order to get a better assessment over average rainfall amounts.

• SOIL TESTS FOR PLOTS

Objectives/Performance Targets

*Determine best means and rate of ash application, considering area coverage, labor requirements, vegetation response and impact on RDM.

*Analyze soil and vegetation differences between ash treated and untreated areas.

*Determine forage production changes.

*Record changes in plant diversity and density.

*Observe changes to soil texture, porosity and infiltration rates.

*Determine if grazing season has lengthened.

*Provide outreach to other ranchers and interest groups as to findings, benefits and unforeseen problems.

*Provide outreach to cogeneration plant owners on ash usage, application requirements, time of use and other issues specific to rangeland application.

*Determine carbon baseline data and determine sequestration potential for ash-treated annual rangeland.

*Publish findings and post on website.

Accomplishments/Milestones

Plots were established at two rates at five rangeland sites (10 tons per acre and 20 tons per acre of wood ash).

However, due to lack of moisture reliable yield measurements were impossible.

Therefore, plots were established; AND:

1. No soil or vegetative differences were measured but 25 exclusion enclosures were built.
2. No forage production changes were measured.
3. Plant diversity and density was not measured.
4. Soil texture changes were not measured.
5. Grazing season was not measured.
6. Outreach to producers was not done.
7. Outreach to plant owners was not done.
8. Carbon baseline data/soil nutrient values were measured.

Impacts and Contributions/Outcomes

Impacts were impossible to measure given that 2012 results were unreliable due to lack of moisture on the rangeland plots.

Collaborators: