Agriculture Resources and the Environment

Tree Ratatouille: Growing Vegetables Under Timber Trees

Denis Flores and his wife are small-scale, direct market and U-pick organic vegetable and fruit farmers in southern France who have embarked on a grand experiment—growing vegetables under rows of tall timber trees. The Flores' call their experiment "arbre ratatouille”, or tree ratatouille, after the popular French mixed vegetable stew.

Stakeholder Review

Thank you to all who participated in the California Nitrogen Assessment’s (CNA) Stakeholder Review process.  The California Nitrogen Assessment was designed to respond to stakeholders’ needs, and the review process was an opportunity for the CNA team to hear from you in order to understand how well the assessment meets those needs.

The stakeholder review process for the CNA has concluded. Webinars of summary findings for individual sections of the assessment, and downloadable drafts of final (pre-press) drafts, are available below.

Stakeholder Questions

Through stakeholder engagement in the CNA's early stages, stakeholders generated a large number of questions about nitrogen in California agriculture. We synthesized a large list into overarching research questions, which served as guides for how to focus the California Nitrogen Assessment.

Stakeholder list

Who We're Working With

The California Nitrogen Assessment team is committed to hearing from and working with a diverse group of stakeholders who have interests related to nitrogen application and impacts in California.

Project Outreach and Publications

Project staff engaged with California growers, farm advisors and other extension personnel, and partner organizations throughout the study. 

Project Staff

Dr. Sonja Brodt, Academic Coordinator, UC SAREP and ASI (Project Director)
Dr. Alissa Kendall, Associate Professor, UC Davis Department of Civil and Environmental Engineering
Elias Marvinney, Graduate Student Researcher, UC Davis Plant Sciences Department

Background on Methyl Bromide phase out

Methyl bromide is a broad-spectrum fumigant that is widely used to control insect, pathogen, nematode, weed and rodent pests. Approximately 90% of the methyl bromide use in California is for pre-plant soil fumigation to control soil-borne pathogens and pests principally in strawberries, nursery crops, grapes, and tree fruits and nuts. Postharvest commodity treatment accounts for about 5-10% of the methyl bromide use and is directed largely at insects of nuts, cherries, grapes, raisins, and imported materials.

Pastured Poultry Under Tree and Vine Crops


It’s a warm spring morning in the vineyard-checkered hills of Central Italy, and Silvio Marsan’s 300-acre farm is already bustling with the sounds of free-range organic chickens and turkeys scratching and pecking under the shade of his olive trees. 

Birds enjoy the cover of tall vegetation—so farmers who use an agroforestry system, mixing trees and shrubs with other crops, can provide comfortable cover for free-range poultry and benefit from a consistent supply of rich manure to fertilize their crops.

Orchard Life Cycle Assessment: Findings

This study calculated the GHG emissions, energy use, on-farm water use and six common air pollutants linked to the production of five orchard crops, and considered production stages from orchard establishment through management, post-harvest processing, and orchard removal and disposal. Transportation along the entire orchard life cycle was also included.

Orchard LCA Model Development and Assumptions

LCA Methodology and Framework

LCA is a comprehensive method for estimating and analyzing the environmental impacts of products and services ‘from cradle to grave.’  In the case of orchard production, the analysis is from ‘nursery to farm-gate’ – including manufacturing and shipping of agrochemicals, fuels, materials, and equipment, as well as air emissions from the combustion of fuels and field emissions. For some crops this study also extends beyond the farm gate to include post-harvest and processing operations.