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 next set of cover crops were planted at the end of Nov 2020. These included sunnhemp, Austrian winter pea, daikon radish, oats, and winter rye. Analysis of the soil nutrient and microbial samples collected in August 2020 indicates similar patterns to Year 1: increased bacterial abundance in cover crop treatments, and increased abundance of nitrogen cycling genes with cover crops. In addition, preliminary analyses found that the types of microbes performing denitrification (part of the nitrogen cycle) are completely different under the legume+non-legume cover crops compared to the other treatments. Soil organic matter has also significantly increased under cover crop treatments. There has been an increase in the abundance of bacteria under the canopy of trees in the legume+non-legume treatment. Analysis of weed data from 2020 shows that cover crop planting has resulted in suppressing weeds up to 98% in one location and 69% in the second location. The observed trend in weed suppression is in line with the previous year. The germination and establishment of cover crops in the second location appear to be improving over time, as noted from the comparisons of cover crop density in planted row-middles between 2019 and 2020. 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 at the end of November 2020 with the planting of the next round of cover crops. Data from Year 2 (collected in Aug 2020) is still being analyzed. 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. Quantitative data on root growth (volume, length and area), root dieback, and recent soil moisture dynamics by treatments will be presented in the next quarter. Preliminary evaluation shows that conducting eco-mowing in the row-middles has unremarkable effects on weed emergence and coverage in the tree-rows. 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 cropsThe cover crops survey was drafted and has IRB approval. The survey was also reviewed but faculty, the project team, extension agents, and is waiting one growers comments. Qualtrics was engaged to administer the survey and next steps are outlined. Our initial estimates are that cover crop establishment is cost prohibitive. Therefore, the survey includes a question on willingness to participate in cost-share programs to help with establishment costs. The partial budgeting process is ongoing. Objective 5: Communicate results to growers using field days and extension materialsPreliminary results are being presented at the Soil Science Society of America/American Society of Agronomy meeting in November. Information on cover crops and preliminary data was 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, in the spring of 2021. 2. Please state what work is anticipated for next quarter: Analysis of soil inorganic N fractions (ammonium and nitrate) for samples collected in August 2020 continues and updates on other soil/leaf nutrient variables will be provided in the next quarter. DNA from soil samples collected in August 2020 has been extracted and microbial analysis has been completed (see above). Weed data analysis will be continued and weed density data collection for the 2021 spring planting will occur in early Summer 2021. Canopy and trunk size measurements and leaf nutrient status along with root image collections and soil moisture monitoring will continue, and quantitative differences reported in the next quarter. The next set of cover crops are scheduled to be planted in May 2021. 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. The cover crop survey will be administered, and data analysis will begin. Partial budgeting analysis will continue. 3. Please state budget status (underspend or overspend, and why): We are on track with our planned budget spending.