1. Please state project objectives and what work was done this quarter to address them:Objective 1: Determine how different cover crop mixtures impact soil and root health and weed cover in established commercial citrus groves.The cover crops planted in November 2019 were mowed in May 2020, and the summer/fall cover crops were planted on May 15 and 19, 2020. Legume cover crops were sunnhemp and cowpea, and non-legumes were brown top millet, Egyptian wheat (similar to sorghum sudangrass), and buckwheat. Germination counts and weed density measurements were made in July, and data is being analyzed. After 1 year of cover crop treatments, soil organic matter significantly increased in the row middles treated with cover crops for both locations. In addition, there were significant changes to the abundance of soil bacteria, particularly bacteria critical for nitrogen cycling, and soil nitrogen concentrations in the row middles planted with the legume cover crop mixes. Planting cover crop mixtures improved the biodiversity of vegetation in the row-middles and changed the composition of weeds. Sedges and grasses were the predominant weed species in row-middles without cover crop plantings, whereas more broad-leaved vegetation was found in cover cropped row-middles. Objective 2: Examine the impact of eco-mowing in conjunction with cover crops on soil and root health and weed cover in established commercial citrus groves.Eco-mowing occurred in early May 2020 when cover crops were mowed in anticipation of planting the next set of cover crops. After a year of treatment, soil organic matter slightly increased (in the range of 0.3-0.5%) under the tree canopy receiving eco-mowing compared to regular cover crop treatments; however, no significant differences were detected between treatments. Visual root growth assessments show continued root growth under cover cropping and eco-mowing, but analysis is ongoing. Soil moisture appears to be similar across all treatments, possibly due to the presence of a high water table at both sites. Objective 3: Quantify the effect of cover crops and eco-mowing on tree growth and production.After 1 year of study, we have not yet observed differences in fruit yield, fruit quality, canopy volume, and trunk size. This is not unexpected, as trees of this age could take at least two years to show responses to treatments. We will continue to assess canopy volume and trunk size, and harvest data will be collected again in Spring 2021. Objective 4: Identify the economic benefits of using cover cropsA student was trained on partial budgeting and valuing soil health. The student began work on developing a citrus budget that is appropriate for comparing management strategies with cover crops relative to business as usual. We found that differences in how the budgets are reported limits historical data collection to five years. These data will be used as a benchmark when doing partial budgeting, which is now in its early stages. In addition to budget ta.60sks, the relevant literature was reviewed and incorporated into a draft of the adoption survey. The survey is ready for review and IRB approval. Objective 5: Communicate results to growers using field days and extension materialsPreliminary results are being presented at the Citrus Expo in August. Initial results on weed suppression by cover crops was included in a presentation at this years Citrus Growers Institute. Information on cover crops and preliminary data will be included in two articles for the Citrus Industry magazine in September. Discussions are underway about how to host a field day, or a virtual field day, at some point in the next year. 2. Please state what work is anticipated for next quarter: The most recent collection of soils, leaves, and roots for microbial and nutrient analysis will be completed by the end of August 2020. Microbial DNA will be extracted from soils collected in August 2020 and analysis of soil microbes important in nitrogen cycling will begin. Soils collected in August 2020 will also be analyzed for soil organic matter and nutrients. Analysis of data from weed density measurements will be performed. Canopy and trunk size measurements and leaf nutrient status along with root image collections and soil moisture monitoring will continue in the next quarter. A graduate student and postdoctoral research associate on the project will be presenting results of the project at American Society of Agronomy virtual annual meeting in November 2020. The next set of cover crops are scheduled to be planted in October. The composition of the mixes is still being discussed. The economics team expects to execute the adoption survey and begin analysis. They will also construct the framework for partial budgeting and assessing the cost of cover crop use and continue to collect data. 3. Please state budget status (underspend or overspend, and why): We are on track with our planned budget spending.