Research & Project Database
Fertilizer Research And Education Program
Research and Project Database
Since 1990, FREP has funded research on many of California’s important and environmentally sensitive cropping systems. This database aims to make the wealth of information contained in FREP research projects available, understandable, and convenient for growers to implement. See the Crop Fertilization Guidelines for tips on how to improve nutrient management, based on information gleaned from research.
Current Projects
The following is a list of FREP projects that are currently being conducted. Each title links to the project's approved proposal and scope of work. Summaries of many of these projects are featured in previous FREP Conference Proceedings.
Copies of interim and annual project reports are available by contacting FREP at (916), 900-5022 or FREP@cdfa.ca.gov.
2025
Reducing Orchard Nitrate Leaching to Groundwater with HFLC and AgMAR: Ground-Truthing and Guiding the ILRP Assessment Tool (25-0499), Thomas Harter
Nitrogen Runoff and Leaching Loss from Nursery Production (25-0500), Christopher Shogren
Development of Diagnostic Tools to Support Site-Specific N Management Decisions in Organic Cropping Systems (25-0501), Paul Zerbe
Advancing Irrigation and Nitrogen Management of Cantaloupe in Southern California using Field Experiments and Remote Sensing (25-0502), Amir Verdi
Nutrient Management: A Collaborative Approach between Agriculture and Regulatory Programs in the San Diego Region (25-0503), Valerie Mellano
Developing Tools and Information to Enhance Water-Nitrogen Use Efficiency and Sustainability of Avocado Production Systems (25-0504), Ali Montazar
2024
A science-based and interactive website for nutrient management in organic crop production (24-0474), Daniel Geisseler
Determination of crop N‐removal coefficient values for the Imperial and Coachella Valleys cropping systems (24-0475), Ali Montazar
Monitoring and assessing variability of nutrient status in almond orchards with hyperspectral satellite imagery empowered by artificial intelligence (24-0476), Yufang Jin
Development of Three Citrus Modules in The Decision Support Tool CropManage for Orange, Mandarin, and Lemon (24-0477), Ken Miller
Equity in Nutrient Management Education on the Central Coast of CA (24-0478), Nathan Harkleroad
2023
Optimizing Potassium Fertilization Management in Almond and Pistachio Orchards (23-0526), Patrick Brown
Estimating Mineralization and Nitrogen Utilization from Banded Compost Applications in Drip Irrigated Sweetpotatoes and Processing Tomatoes (23-0522), Daniel Geisseler
Improving Nitrogen and Potassium Management in Almond Orchards with Hulls and Shells as a Soil Amendment and Offground Harvest (23-0525), Sat Darshan Khalsa
Nitrogen Movement Out of Root-Zones in Central Valley Irrigated Lands: A Multi-Scale Management, Monitoring, Modeling, and Outreach Project (23-0523), Isaya Kisekka
No-till planting of Rice to Conserve Water and Ensure the Sustainability of Rice Systems (23-0524), Bruce Linquist
Facilitating Grower Adoption of Cover Crop Nitrogen Scavenging to Minimize Residual Nitrogen Loss and Comply with the Irrigated Lands Water Quality Protection Program (Ag Order 4.0), on the Central Coast of CA (23-0519), Sacha Lozano
2022
Developing Tools and Information on Irrigation and Nitrogen Best Management Practices in California's Low Desert Lettuce Production Systems (22-1312), Ali Montazar
The Role of Irrigation Management for Improving Nitrogen Use Efficiency for Broccoli Grown with Nitrate-Contaminated Irrigation Water (22-1454), Charlotte Decock
2021
Optimizing Nitrogen Fertilizer Concentrations in Vegetable Transplant Production (21-0587), Lorence Oki
Nitrogen Fertilizer and Irrigation Best Management Practices for the Low Desert Sudangrass Production Systems Project (21-0586), Oli Bachie
Quantify and Model Overlooked Pathways of Nitrogen Loss From Organic Inputs Across Contrasting Soil Types (21-0588), Timothy Bowles
2020
"Crop Nutrient Minute" Video Series (20-0877), Parry Klassen
Completed Projects
The following is a list of completed FREP projects. Each title links to a PDF of the project's final report. Summaries of many of these projects are available in the FREP Research Database andFREP Conference Proceedings. Some Project Leaders have published their results in academic journals. Reprints of the journal publications may be requested directly from the corresponding authors.
2022
Development of Precision Yield Monitor for Almond and Pistachio (22-1455), Deborah Nares
2021
2020
Nitrogen Content of the Harvested Portion of Specialty Crops to Estimate Crop Nitrogen Removal and Improve Nitrogen Management in Crops (20-0250), Richard Smith, Michael Cahn, Aparna Gazula and Andre Biscaro
Assessment of Harvested and Sequestered Nitrogen Content to Improve Nitrogen Management in Crops, Phase 2 (20-0879), Daniel Geisseler
Development of Site-Specific Nitrogen Fertilization Recommendations for Annual Crops (20-0880), Daniel Geisseler
Enhancing Nitrogen and Water Use Efficiency in California Carrot Production Through Management Tools and Practices (20-0960), Ali Montazar, Daniel Geisseler, Michael Cahn and Jaspreet Sidhu
Certification and Distance Learning for Fertigation (20-0961), Stuart Styles
University of California Nursery and Floriculture Alliance Fertilizers and Plant Nutrition Workshops for Greenhouse and Nursery Growers (20-0963), Lorence Oki
Nitrogen Response of Industrial Hemp Cultivars Grown for CBD, Essential Oils, and Fiber (20-0964), Robert B. Hutmacher, Daniel H. Putnam
Techniques to Minimize Nitrate Loss from the Root Zone During Managed Aquifer Recharge (20-1019), Anthony Toby O’Geen and Helen Dahlke
2019
Promoting the adoption of CropManage to optimize nitrogen and irrigation use through technical assistance with data loggers and cellular modems for Spanish speaking growers in Santa Cruz and Monterey Counties (19-0950), Sacha Lozano
Next Generation N Management Training for Certified Crop Advisors (19-0951), Sat Darshan Khalsa, Erik Porse, Marina Vergara and Amanda Crump
Developing a nitrogen mineralization model for organically managed vegetable farms on the Central Coast (19-0952), Joji Muramoto, Richard Smith, Michael Cahn, and Daniel Geisseler
Achieving Efficient Nitrogen Fertilizer Management in California Wheat (19-0953), Mark Lundy
Development of Nutrient Budget and Nutrient Demand Model for Nitrogen Management in Cherry (19-0954), Patrick Brown, Douglas Amaral and Ricardo Camargo
Immobilization of Nitrate in Winter-Fallow Vegetable Production Beds to Reduce Nitrate Leaching (19-0955), Richard Smith, Michael Cahn, Joji Muramoto and Daniel Geisseler
Irrigation and Nitrogen Management, Monitoring, and Assessment to Improve Nut Production While Minimizing Nitrate Leaching to Groundwater (19-0968), Thomas Harter, Patrick Brown and Isaya Kisekka
2018
Promoting the adoption of soil nitrogen quick tests by Spanish-speaking operators on strawberry ranches in Santa Cruz and Monterey Counties (18-0535), Gerry Spinelli
Improving nitrate and salinity management strategies for almond grown under micro-irrigation (18-0549), Patrick Brown
Assessing Drip Irrigation and Nitrogen Management of Fresh Onions Produced in California Low Desert (18-0592), Jairo Diaz
Efficient Water and Nitrogen Management Practices for Mixed Leafy Baby Green Vegetables in the Desert (18-0593), Charles A. Sanchez and Andy French
Understanding Influences on Grower Decision–Making and Adoption of Improved Nitrogen Management Practices in the Southern San Joaquin Valley (18-0596), Sat Darshan Khalsa and Mark Lubell
Pima Cotton Nitrogen Management, Uptake, Removal - Impacts of Varieties, Subsurface Drip & Furrow Irrigation (18-0597), Robert Hutmacher
2017
Training on Crop Management and Integrated Climate, Soil and Irrigation System Data to Minimize Nutrient Loss and Optimize Irrigation Efficiency(17-0489), Trina Walley
Assessment of Harvested and Sequestered Nitrogen Content to Improve Nitrogen Management in Perennial Crops (17-0488), Charlotte Gallock
Evaluation of Nitrogen Uptake and Applied Irrigation Water in Asian Vegetables Bok Choy, Water Spinach, Garlic Chives, Moringa, and Lemongrass (17-0515), Aparna Gazula, Ruth Dahlquist-Willard and Daniel Geisseler
A system nitrogen balance for container plant production (17-0516), Lorence R. Oki, William Horwath and Richard Evans
2016
Evaluation of Biochar for On-Farm Soil Management in California (16-0662), Sanjai Parikh and Danielle Gelardi
Evaluation of certified organic fertilizers for long-term nutrient planning (16-0670), William Horwath and Xia Zhu-Barker
University of California Nursery and Floriculture Alliance Fertilizers and Plant Nutrition Education Program (16-0678), Lorence Oki et al
Developing a Review Process for Continuing Education Courses for Growers who Complete the Nitrogen Management Plan Training Course (16-0703), Parry Klassen
Expanding the California Fertilization Guidelines to Support Nutrient Management Decisions for Minor Crops (16-0610), Daniel Geisseler
Understanding Influences of Grower Decision-making and Adoption ofImproved Nitrogen Management Practices (16-0620), Mark Lubell
Citrus Early Leaf Sampling (16-0707), Patrick Brown
Combined New Leaf Sampling Technique for Nitrogen Analysis and Nitrogen Application Approach in Almonds (16-0708), Patrick Brown
Online Decision Support Tools for Irrigation and Nitrogen Management ofCentral Valley Crops (16-0710), Michael Cahn
Soil biochar amendment to improve nitrogen and water management (16-0597), Suduan Gao
2015
Evaluation of the Multiple Benefits of Nitrogen Management Practices in Walnuts (15-0360), Parry Klassen
Prediction of summer leaf nitrogen concentration from early season samples to better manage nitrogen inputs at the right time in walnuts, prunes, and pears (15-0492), Patrick Brown et al
Evaluation and demonstration of nitrogen management of organic vegetable production in leafy green vegetables on the Central Coast (15-0522), Richard Smith et al
Train the Trainer: A Nitrogen Management Training Program for Growers(15-0392), Klassen
Improving Nitrate and Salinity Management Strategies for Almonds Grown under Micro-Irrigation (15-0523), Patrick Brown
New Fertigation Book (15-0393), Charles Burt
Developing a decision support tool for processing tomato irrigation and fertilization in the Central Valley based on CropManage (15-0410), Daniel Geisseler
Quantifying N2O Emissions under Different On-farm Irrigation and Nutrient Management BMPs that Reduce Groundwater Nitrate Loading and AppliedWater (15-0356), Arlene Haffa
Prediction of Summer Leaf Nitrogen Concentration from Early Season Samplesto Better Manage Nitrogen Inputs at the Right Time in Walnuts, Prunes, and Pears (15-0492), Patrick Brown, Emilio Laca, and Sebastian Saa
Online Fertilization Guidelines for Agricultural Crops in California (15-0231), Daniel Geisseler
Nitrogen Fertilizer Loading to Groundwater in the Central Valley(11-0301-SA and 15-0454-SA), Thomas Harter, et al.
Evaluation and Demonstration of Nitrogen and Phosphorous Management in Organic Leafy Green Vegetables Production on the Central Coast(15-0522), Richard Smith, Michael Cahn, and Tim Hartz
2014
Development of Management Training Curriculum for Use in Grower Training for Self-Certification of Regional Water Board Nitrogen Management Plans (14-0585),
Terry Prichard and Larry Schwankl
A Data Driven Nitrate Leaching Hazard Index and BMP Assessment Tool (14-0452), Toby O’Geen and Jan Hopmans
Improving N Field Evaluation and Demonstration of Controlled Release N Fertilizers in the Western United States (14-0508), Charles A. Sanchez and Richard Smith
California Certified Crop Adviser FREP Educational Project(14-0555), Daniel H. Putnam and Terry W. Stark
Field Evaluation and Demonstration of Controlled Release N Fertilizers in the Western United States (14-0508), Charles Sanchez
Plant Nutrients in the Classroom (14-0481), Judy Culbertson and Austin Miller
2013
Developing Nitrogen Management Strategies to Optimize Grain Yield andProtein Content while Minimizing Leaching Losses in California Wheat (13-0267-SA), Robert Hutmacher, Steve Orloff, Steve Wright, and Mark Lundy
Nitrogen Management Training for Certified Crop Advisors (13-0241-SA), Doug Parker, Patrick Brown, Allan Fulton, Tim Hartz, Dan Munk, Stuart Pettygrove, Lawrence Schwankle
Phosphorus and Boron Fertilizer Impacts on Sweetpotato Production andLong-Term Storage (13-0266-SA), C. Scott Stoddard
Improving N Use Efficiency of Cool Season vegetable Production Systemswith Broccoli Rotations (13-0268-SA), Richard Smith, Michael Cahn, and T.K. Hartz
2012
Measuring and Modeling Nitrous Oxide Emissions from California Cotton and Vegetable Cropping Systems (12-0452), Dave Goorahoo
Determining the Fertilizer Value of Ambient Nitrogen in Irrigation Water (12-0455-SA), Michael Cahn, Richard Smith, and T.K. Hartz
Development of Economically Viable Variable Rate P Application Protocols for Desert Vegetable Production Systems (12-0386-SA), Charles A. Sanchez, Pedro Andrade-Sanchez, and Kurt Nolte
Evaluation of N Uptake and Water Use on Leafy Greens Grown in High Density Bed Plantings and Demonstration of Best Management Practices (12-0362-SA), Richard Smith and Mike Cahn
Characterizing N Fertilization Requirements of Crops Following Alfalfa (12-0385-SA), Dan Putnam and Stu Pettygrove
Evaluation of a 24 Hour CO2 Test for Estimating Potential N-Mineralization to Reassess Fertilizer N Recommendations (12-0384-SA), William R. Horwath, Martin Burger, and Jeffery Mitchell
Assessment of Baseline Nitrous Oxide Emissions in Response to a Range of Nitrogen Fertilizer Application Rates in Corn Systems (12-0453-SA), Martin Burger and William R. Horwath
Fertigation Education for the San Joaquin Valley (12-0390-SA), William Green and Kaomine Vang
Improving Pomegranate Fertigation and Nitrogen Use Efficiency with Drip Irrigation Systems (12-0387-SA), James E. Ayars and Claude J. Phene
Optimizing the Use of Groundwater Nitrogen for Nut Crops (12-0454-SA), David R. Smart, Patrick Brown, Thomas Harter, and Jan Hopmans
2011
How much it too much? How little is too little? / Educator's Guide to Fun with the Plant Nutrient Team (11-0454-SA), Judy Culbertson
Improved Methods for Nutrient Tissue Testing in Alfalfa (11-0469-SA), Steve Orloff
Nitrogen Fertilizer Loading to Groundwater in the Central Valley (11-0301-SA and 15-0454-SA), Thomas Harter, et al.
Exploring the Potential for Using Transgenic Crops for Improved Fertilizer Use Efficiency (11-0453-SA), Charles A. Sanchez and Roberto Gaxiola
Determination of Root Distribution, Dynamics, Phenology and Physiology of Almonds to Optimize Fertigation Practices (11-0461-SA), Patrick Brown
Remediation of Tile Drain Water Using Bioreactors (11-0462-SA), T.K. Hartz, Richard Smith, Mike Cahn, and Laura Tourte
California Certified Crop Advisor FREP Educational/Outreach Project (11-0470-SA), Dan Putnam
Survey of Nitrogen Uptake and Applied Irrigation Water in Broccoli,Cauliflower, and Cabbage Production in the Salinas Valley (11-0558-SA), Richard Smith, Mike Cahn, and T.K. Hartz
Optimization of Organic Fertilizer Schedules (11-0456-SA), David M. Crohn and Marsha Campbell Mathews
Management Tools for the Fertilization of the 'Hass' Avocado (11-0437-SA), Richard Rosecrance and Carol J. Lovatt
Assessment of Plant Fertility Requirements for Agricultural Crops in California (11-0485-SA), William R. Horwath and Daniel Geisseler
2010
Irrigation and Nitrogen Management Web-Based Software for Lettuce Production (10-0013-SA), Michael Cahn
Relationship of Soil K Fixation and Other Soil Properties to Fertilizer K Rate Requirement (10-0012-SA), G. Stuart Pettygrove
Development of a Nutrient Budget Approach to Fertilizer Management in Almond (10-0039-SA), Patrick Brown
Nitrogen Research & Groundwater Management Education Program (10-0011-SA), Renee Pinel
Adjustable-Rate Fertigation for Site-Specific Management to Improve Fertilizer Use Efficiency (10-0004-SA), Michael Delwiche
Chemistry, Fertilizer, and the Environment – A Comprehensive Unit (10-0010-SA), Judy Culbertson, Shaney Emerson, and Lyn Hyatt
Development of Leaf Sampling and Interpretation Methods for Almond and Pistachio(10-0015-SA), Patrick Brown
European Pear Growth and Cropping: Optimizing Fertilizer Practices Based on Seasonal Demand and Supply with Emphasis on Nitrogen Management (10-0105-SA), Kitren Glozer and Chuck Ingels
2009
Citrus Yield and Fruit Size Can Be Sustained for Trees Irrigated with 25% or 50% less Water by Supplementing Tree Nutrition with Foliar Fertilization - Comparison of Conventional Irrigation and Partial Root Zone Drying at the Same Reduced Irrigation Rates Supplemented with Equal Foliar Fertilization (09-0581), Carol J. Lovatt and Ben Faber
Developing Testing Protocols to Assure the Quality of Fertilizer Materials for Organic Agriculture (09-0582), W.R. Horwath and S.J. Parikh
Improving Pomegranate Fertigation and Nitrogen Use Efficiency with Drip Irrigation Systems
(09-0583), James E. Ayars and Claude J. Phene
2008
Development of a Comprehensive Nutrient Management Web site for the California Horticultural Industry (08-0629), T.K. Hartz
Evaluation Low-Residue Cover Crops to Reduce Nitrate Leaching, and Nitrogen and Phosphorous Losses from Winter Fallow Vegetable Production Fields in the Salinas Valley (08-0628), Richard Smith and Michael Cahn
Western Fertilizer Handbook Turf & Ornamental Edition (08-0007), Renee Pinel and Pamela Emery
2007
Can a Better Tool for Assessing 'Hass' Avocado Tree Nutritional Status Be Developed? A Feasibility Study (07-0002), Carol J. Lovatt, Richard Rosecrance, and Ben Faber
Comparing the Efficiency of Different Foliarly-Applied Zinc Formulations on Peach and Pistachio Trees by Using 68Zn Isotope (07-0669), R. Scott Johnson
Development and Implementation of Online, Accredited Continuing Education Classes on Proper Sampling and Application of Nitrogen/Crop Nutrients (07-0223), Renee Pinel, et al.
Development of Certified Crop Adviser Specialty Certification and Continuing Education in Manure Nutrient Management (07-0405), Stuart Pettygrove
Evaluation of Humic Substances Used in Commercial Fertilizer Formulations (07-0174), T.K. Hartz
Fertilizer Education Equals Clean Water (07-0120), Kay Mercer and Kevin Peterson
New Standard for the Effectiveness of Foliar Fertilizers (07-0667), Carol J. Lovatt
Optimizing Nitrogen Availability in Cherry Growth to Obtain High Yield and Fruit Quality (07-0666), Kitren Glozer, Gregory Lang, and Joe Grant
2006
Development of a Model System for Testing Foliar Fertilizers, Adjuvants and Growth Stimulants (06-0624), Patrick Brown
Development of Practical Fertility Monitoring Tools for Drip-Irrigated Vegetable Production (06-0626), Tim Hartz
Site-Specific Fertilizer Application in Orchards, Nurseries and Landscapes (06-0600), Michael Delwiche, et al.
2004
Detecting and Correcting Soil Calcium Limitations (04-0701), T.K. Hartz, Richard Smith, and Mike Cahn
Fertility Management in Rice (04-0704), Chris van Kessel and Bruce Linquist
Fertilization Technologies for Conservation Tillage Production Systems in California (04-0808), Jeff Mitchell, et al.
Improving Water-Run Nitrogen Fertilizer Practices in Furrow and Border Check – Irrigated Field Crops (04-0747), Stuart Pettygrove
2003
Hiring a Landscape Company - What You Should Know Before You Start (03-0654), Valerie J. Mellano
Improving the Procedure for Nutrient Sampling in Stone Fruit Trees (03-0652), R. Scott Johnson
Increasing Yield of the 'Hass' Avocado by Adding P and K to Properly Timed Soil N Applications (03-0653), Carol J. Lovatt
Potassium Fertility Management for Optimum Tomato Yield and Fruit Color (03-0651), Tim Hartz
Precision Fertigation in Orchards: Development of a Spatially Variable Microsprinkler System (03-0655), Michael Delwiche, et al.
Reevaluating Tissue Analysis as a Management Tool for Lettuce and Cauliflower(03-0650), T.K. Hartz
Soil-Solution Partitioning of Trace Elements in Cropland Soils of California (03-0088), Andrew C. Chang, Weiping Chang, and Albert L. Page
2002
Determination of Nursery Crops Yields, Nutrient Content, and Water Use for Improvement of Water and Fertilizer Use Efficiency (02-0651), Richard Y. Evans and Linda L. Dodge
Evaluation of Polyacrylamide (PAM), for Reducing Sediment and Nutrient Concentration in Tail Water from Central Coast Vegetable Fields (02-0781), Michael Cahn, Husein Ajwa, and Richard Smith
Practical Soil Test Methods for Predicting Net N Mineralization (02-0653), W.R. Horwath and G.S. Pettygrove
The Effect of Nutrient Deficiencies on Stone Fruit Production and Quality (02-0691), R. Scott Johnson
2001
California State Fair Farm Upgrade Project (01-0640), Michael Bradley, Joe Brengle, and Teresa Winovitch
Crop Nitrate Availability and Nitrate Leaching under Micro-Irrigation for Different Fertigation Strategies (01-0545), Blaine Hanson and Jan W. Hopmans
Development of a Leaf Color Chart for California Rice Varieties (01-0510), Randall G. Mutters
Development of BMPs for Fertilizing Lawns to Optimize Plant Performance and Nitrogen Uptake While Reducing the Potential for Nitrate Leaching (01-0508), Robert Green, et al.
Development of Lime Recommendations for California Soils (01-0511), Robert O. Miller, Janice Kotuby-Amacher, and Nat Dellavalle
Effects of Cover Cropping and Conservation Tillage on Sediment and Nutrient Losses to Runoff in Conventional and Alternative Farming Systems (01-0473), William R. Horwath, et al.
Efficient Phosphorus Management in Coastal Vegetable Production (01-0509), T.K. Hartz
Evaluating the Impact of Nutrient Management on Groundwater Quality in the Presence of Deep Unsaturated Alluvial Sediment (01-0584), Thomas Harter, et al.
Fertilization Technologies for Conservation Tillage Production Systems in California (01-0123), Jeff Mitchell and Willi Horwath
Site-Specific Variable Rate Fertilizer Nitrogen Application in Cotton (01-0507), Richard E. Plant, et al.
2000
Ammonia Emission Related to Nitrogen Fertilizer Application Practices (00-0515), Charles F. Krauter
Effect of Different Rates of N and K on Drip-Irrigated Beauregard Sweetpotatoes (00-0507), Scott Stoddard and Bob Weimer
Evaluation of Slow Release Fertilizers for Cool Season Vegetable Production in the Salinas Valley (00-0506), Richard Smith and Tim Hartz
From the Ground Up: A Step-By-Step Guide to School Gardening (00-0072), Jennifer Lombardi
Improving the Diagnostic Capabilities for Detecting Molybdenum Deficiency in Alfalfa and Avoiding Toxic Concentrations for Animals (00-0516), Roland D. Meyer, Daniel B.Marcum, and Steve Orloff
Location of Potassium-Fixing Soils in the San Joaquin Valley and a New, Practical Soil K Test Procedure (00-0508), G. Stuart Pettygrove and Randal J. Southard
Long Term Rice Straw Incorporation: Does It Impact Maximum Yield? (00-0651), Chris van Kessel and William R. Horwath
Minimizing Nitrogen Runoff and Improving Nitrogen Use Efficiency in Containerized Woody Ornamentals through Management of Nitrate and Ammonium-Nitrogen (00-0509), Donald J. Merhaut and Richard Y. Evans
On-Farm Monitoring and Management Practice Tracking for Central Coast Watershed Working Groups (00-0071), Kelly Huff
Precision Horticulture: Technology Development and Research and Management Applications (00-0497), Patrick H. Brown
Reducing Fertilizer Needs of Potato with New Varieties and New Clonal Strains of Existing Varieties (00-0514), Ronald E. Voss
Residual Soil Nitrogen and Nitrogen Management for Alcala Cotton(00-0604), R.B. Hutmacher, et al.
Seasonal Patterns of Nutrient Uptake and Partitioning as a Function of Crop Load of the 'Hass' Avocado (00-0621), Richard Rosecrance and Carol J. Lovatt
Site-Specific Variable Rate Fertilizer Application in Rice and Sugar Beets (00-0505), Richard E. Plant, et al.
Teach the Teachers: Garden-Based Education about Fertility and Fertilizers (00-0070), Peggy Sears Perry
1999
Evaluating and Demonstrating the Effectiveness of In-Field Nitrate Testing in Drip- and Sprinkler-Irrigated Vegetables (99-0756), Marc Buchanan
Nitrogen Budgeting Workshops (99-0757), Molly Johnson and Gwen Huff
Pajaro Valley Nutrient Management Education & Outreach Project (99-0764), U Win and Frank Shields
The Role of Inorganic Chemical Fertilizers and Soil Amendments on Trace Element Contents of Cropland Soils in California (99-0533), Andrew C. Chang
1998
Air Quality and Fertilization Practices: Establishing a Calendar of Nitrogen Fertilizer Application Timing Practices for Major Crops in the San Joaquin Valley (98-0471), Jack King, Jr.
Demonstration of Presidedress Soil Nitrate Testing as an N Management Tool (98-0513), Tim Hartz
Effect of Cover Crop or Compost on Potassium Deficiency and Uptake, and on Yield and Quality in French Prunes (98-0422), Richard Rosecrance, P. A. Delwiche, and Fred Thomas
Efficient Irrigation for Reduced Non-Point Source Pollution from Low Desert Vegetables(98-0423), Charles. A. Sanchez, Dawit Zerihun, and Khaled. M. Bali
1997
Agricultural Baseline Monitoring and BMP Implementation: Steps Towards Meeting TMDL Compliance Deadlines within the Newport Bay/San Diego Creek Watershed (97-0365 M99-01), Laosheng Wu and John Kabashima
Agriculture and Fertilizer Education for Grades K-12 (97-0361), Pamela Emery, Richard Engel, and Judy Culbertson
Development and Demonstration of Nitrogen Best Management Practices for Sweet Corn in the Low Desert (97-0365 M98-02), Jose L. Aguiar, et al.
Development and Testing of Application Systems for Precision Variable Rate Fertilization (97-0365 M97-06A), Ken Giles
Development of an Educational Handbook on Fertigation for Grape Growers (97-0365 M99-07), Glenn McGourty
Development of Fertilization and Irrigation Practices for Commercial Nurseries (97-0365 II M99-03), Richard Y. Evans, Carmen Garcia-Navarro, and Linda L. Dodge
Development of Irrigation and Nitrogen-Fertilization Programs on Tall Fescue to Facilitate Irrigation-Water Savings and Fertilizer-Use Efficiency (97-0365 M97-07), Robert L. Green, Grant J. Klein, and Victor A. Gibeault
Development of Nitrogen Best Management Practices for the "Hass" Avocado (97-0365 M98-01), Carol J. Lovatt
Drip Irrigation and Fertigation Scheduling for Celery Production (97-0365 M97-02), T.K. Hartz
Nitrogen Mineralization Rate of Biosolids and Biosolids Compost (97-0365 M99-10), T.K. Hartz
Interaction of Cotton Nitrogen Fertility Practices and Cotton Aphid Population Dynamics in California Cotton (97-0365 M98-04), Larry D. Godfrey and Robert Hutmacher
Long-Term Nitrate Leaching Below the Root Zone in California Tree Fruit Orchards (97-0365 M97-04), Thomas Harter, et al.
Nitrogen Budget in California Cotton Cropping Systems (97-0365 M97-09), William Rains, Robert L. Travis, and Robert Hutmacher
Nitrogen Fertilization and Grain Protein Content in California Wheat (97-0365 M99-04), L.F. Jackson
Potassium Responses in Rice Fields as Affected By Straw Management Practices(97-0365 M99-08), Chris van Kessel, et al.
Relationship between Fertilization and Pistachio Diseases (97-0365 M99-06), Themis J. Michailides and Patrick Brown
Soil Testing to Optimize Nitrogen Management for Processing Tomatoes (97-0365 M97-03), Don May and Jeff Mitchell
Uniformity of Chemigation in Micro-irrigated Permanent Crops (97-0365 M97-008), Larry Schwankl and Terry Pritchard
Water and Fertilizer Management for Garlic: Productivity, Nutrient and Water Use Efficiency and Postharvest Quality (97-0207), Marita Cantwell, et al.
Winter Cover Crops Before Late-Season Processing Tomatoes for Soil Quality and Production Benefits (97-0365 M99-11), Gene Miyao, Paul Robins, and Mike Cahn
1996
Development of a Nitrogen Fertilizer Recommendation Model to Improve N-Use Efficiency and Alleviate Nitrate Pollution to Groundwater from Almond Orchards (96-0367), Patrick H. Brown
Fertilizer Use Efficiency and Influence of Rootstocks on Uptake and Nutrient Accumulation in Winegrapes (96-0399), Larry E. Williams
Improving Fertilizer Practices of SE Asians in Fresno and Tulare Counties (96-0405), Richard Molinar and Manuel Jimenez
Management of Nitrogen Fertilization in Sudangrass for Optimum Production, Forage Quality and Environmental Protection (96-0400), D. Putnam
Nitrogen Management in Citrus under Low Volume Irrigation (96-0280), M.L. Arpaia and L.J. Lund
Survey of Changes in Irrigation Methods and Fertilizer Management Practices in California (96-0371), John Letey, Jr.
1995
Avocado Growers Can Reduce Soil Nitrate Groundwater Pollution and Increase Yield and Profit (95-0523), Carol J. Lovatt
Best Management Practices (BMPs), for Nitrogen and Water Use in Irrigated Agriculture: A Video (95-0463), Larry Klaas and Thomas Doerge
Determination of Best Nitrogen Management Practices for Broccoli Production in the San Joaquin Valley (95-0520), Michelle Le Strange, Jeffrey P. Mitchell, and Louise E. Jackson
Development and Promotion of Nitrogen Quick Tests for Determining Nitrogen Fertilizer Needs of Vegetables (95-0582), Richard Smith and Kurt Schulbach
Diagnostic Tools for Efficient Nitrogen Management of Vegetables Produced in the Low Desert (95-0222), C.A. Sanchez
Evaluation of Controlled Release Fertilizers and Fertigation in Strawberries and Vegetables (95-0418), Warren E. Bendixen
Evaluation of Pre-Sidedress Soil Nitrate Testing to Determine N Requirements of Cool Season Vegetables (95-0583), T.K. Hartz, Warren Bendixen, and Kurt Schulbach
Guide to Nitrogen Quick-Tests for Vegetables with the 'Cardy' Nitrate Meter (95-0582), Kurt Schulbach, et al.
Irrigation and Nutrient Management Conference and Trade Fair (95-0419), Danyal Kasapligil
Relationship between Fertilization and Bacterial Canker Disease in French Prune (95-0478), Steven Southwick, Bruce Kirkpatrick, and Becky Westerdah
Site Specific Farming Information Systems in a Tomato-Based Rotation in the Sacramento Valley (95-0518), Stuart Pettygrove, et al.
Using High Rates of Foliar Urea to Replace Soil Applied Fertilizer in Early Maturing Peaches (95-0214), R. Scott Johnson and Richard Rosecrance
1994
Best Management Practices for Tree Fruit and Nut Production: A Video (94-0463), Thomas Doerge and Larry Klaas
Education through Radio (94-0517), Patrick Cavanaugh
Effects of Four Levels of Applied Nitrogen on Three Fungal Diseases of Almond Trees (94-0513), Beth L. Teviotdale
Effects of Various Phosphorus Placements on No-Till Barley Production (94-0450), Michael J. Smith
Improvement of Nitrogen Management in Vegetable Cropping Systems in the Salinas Valley and Adjacent Areas Stuart Pettygrove
Nitrogen Management through Intensive on-Farm Monitoring (94-0362), T.K. Hartz
Nutrient Recommendation Training in Urban Markets: A Video (94-0463), Wendy Jenks and Larry Klaas
1993
Citrus Growers Can Reduce Nitrate Groundwater Pollution and Increase Profits by Using Foliar Urea Fertilization (93-0530), Carol J. Lovatt and Joseph G. Morse
Drip Irrigation and Nitrogen Fertigation Management for California Vegetable Growers: Videotape Timothy K. Hartz
Nitrogen Efficiency in Drip-Irrigated Almonds (93-0551), Robert J. Zasoski
Western States Agricultural Laboratory Proficiency Testing Program (93-0568), R.O. Miller and J. Kotuby-Amacher
1992
Crop Management for Efficient Potassium Use and Optimum Winegrape Quality (92-0627), Mark A. Matthews
Determination of Soil Nitrogen Content In-Situ (92-0575), Shrini K. Updahyaya, Sayedahmed Shafii, and William J. Chancellor
Establishing Updated Guidelines for Cotton Nutrition (92-0589), Bill Weir, et al.
Impact of Microbial Processes on Crop Use of Fertilizers from Organic and Mineral Sources (92-0639), Kate M. Scow
Optimizing Drip Irrigation Management for Improved Water and Nitrogen Use Efficiency (92-0629), Timothy K. Hartz
Potential Nitrate Movement below the Root Zone in Drip-Irrigated Almonds (92-0631), Roland D. Meyer
1991
Demonstration Program for Reducing Nitrate Leaching through Improvements to Irrigation Efficiency and Fertilizer/Cover Crop Management (91-0654), Stuart Pettygrove, et al.
Field Evaluation of Water and Nitrate Flux through the Root Zone in a Drip/Trickle-Irrigated Vineyard (91-0556), Donald W. Grimes
Influence of Irrigation Management on Nitrogen Use Efficiency, Nitrate Movement, and Groundwater Quality in a Peach Orchard (91-0646), R. Scott Johnson and Claude J. Phene
Nitrogen Management for Improved Wheat Yields, Grain Protein and the Reduction of Excess Nitrogen (91-0485), Bonnie Fernandez
FREP
