Evaluation of lime and biochar as sustainable soil amendments for spring canola under acidic soils in the Pacific Northwest

Commodities

• Agronomic: canola

Practices

• Crop Production: varieties and cultivars
• Education and Training: extension, on-farm/ranch research, participatory research
• Production Systems: dryland farming
• Soil Management: soil analysis, soil chemistry, soil quality/health
• Sustainable Communities: food access and security, sustainability measures

Soil acidification is one of the growing challenges in the dryland cropping systems of the inland Pacific Northwest (iPNW). The low soil pH increases aluminum toxicity, and disrupts soil properties, resulting in crop yield losses ranging from 25-80%. Canola, an important rotational crop in the wheat-based cropping system of this region, is sensitive to soil pH below 5.8. Unavailability of the acid-tolerant canola cultivars is another challenge for the growers. Liming is recommended to improve soil pH, but its adoption is limited due to cost, logistics, issues with soil properties, and inconsistent crop performance. To search for strategies to manage acidic soils, we plan to test and compare the performance of lime with biochar, which is considered more sustainable and potentially a long-term solution for acidic soil. This research aims to determine the effects of lime and biochar on soil physical and chemical properties in acidic soils and assess how spring canola cultivars respond to these soil amendments. Altogether, four on-farm experiments are planned for two years at two locations with acidic soils using lime and biochar treatments, using six spring canola cultivars. This study will quantify changes in soil properties, crop growth, yield, and stability across soil amendment treatments, locations, and years. The findings will be disseminated to stakeholders through field days, grower meetings, conferences, and both research and extension publications. Expected outcomes include improved decision-making among producers, enhanced canola productivity, and increased adoption of sustainable soil management strategies that support improved soil health, and long-term profitability in iPNW.

Research objectives:

1. Compare the effects of lime and biochar on soil physical and chemical properties in acidic soils.
2. Evaluate the agronomic performance of six spring canola cultivars under lime, biochar, and acidic soil conditions.
3. Identify the cultivars with consistent yield performance across soil amendments to guide cultivar selection for the growers

Educational objectives:

1. Work closely with experienced producer collaborators to share and exchange scientific and practical agricultural knowledge.
2. Present the research findings at professional and growers' meetings, departmental seminars, and conferences to share insights on the efficacy of lime and biochar in managing soil acidity, improving soil health, and their influence on canola cultivar performance.
3. Participate in the field days to demonstrate the cultivar response to soil amendments and provide stakeholders with practical take-home materials summarizing key results and practical recommendations.
4. Publish the project findings in the Dryland Field Day Abstracts and peer-reviewed scientific journals to disseminate knowledge to the broader research and producer community.