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Integrated Canopy Management in California Nut Crops

Investigators
Lampinen, Bruce
Institutions
University of California - Davis
Start date
2011
End date
2016
Objective

1) Work to maintain productivity in dense plantings.

2) Assess possibilities of using regulated deficit irrigation and nitrogen manipulation to attempt to regulate vegetative growth.

3) Investigate the role of role of irrigation and canopy management on food safety risk.

4) Investigate the role of tree training on root growth patterns, canopy structure and productivity.

More information

NON-TECHNICAL SUMMARY:
Situation: The increasingly competitive marketplace for tree nuts and consumer demands to decrease pesticide use is pushing growers to increase planting density and push trees into early productivity while trying to minimize pesticide use. The resulting high density planting can increase food safety risk due to cool, moist conditions on the orchard floor being conducive to microbe growth.
Purpose: The purpose of this work is to examine the role of tree training and pruning on long term orchard structure and productivity with the goal of maintaining sustainable productivity in high density plantings. A secondary goal is to investigate the role of canopy management and irrigation on food safety risk in nut crops.

APPROACH:
Field studies will be used to investigate methods of maintaining productivity in high density plantings and the role of irrigation and canopy management in disease and insect resistance as well as food safety risk. Additional work will involve the impacts of different tree training and pruning methods on root growth patterns, long term canopy development and productivity. This work will include detailed investigations of the impacts of training and pruning methods on canopy light interception as measured with a new mobile platform we have developed as well as root growth observations using mini-rhizotron tubes. This information will be used to help develop integrated orchard management practices to maintain productivity while minimizing inputs.

PROGRESS:
2013/01 TO 2013/09
Target Audience: The target audiences for this project have included farm advisors, PCAs, and growers throughout the state of California. Talks have been given related to this project for at least 6-8 annual grower winter meetings and 4-5 annual grower field meetings as well as at the annual walnut and almond meetings. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Objective 1- In the spring of 2008, all treatments were converted to the same nitrogen and water levels which aim for slightly lower levels of water and nitrogen compared to the original high water/high nitrogen treatments. Yields from 2008-2012 yields for the former deficit treatments are nearly equal to those in the high water, high nitrogen treatments after 4 years of similar levels of water and nitrogen application. Although field work on this objective is a largly completed, work is continuing on analyzing data and preparing it for publication. Objective 2- Results in 2008-2013 suggested that variability in canopy size across the orchard resulted in significant differences in moisture content of hulls and nuts such that more mold grew on nuts from the more heavily canopied parts of the orchard. In addition, work is underway evaluating the impact of different types of tarps used during stockpiling on temperature fluctuations and food safety risk. Finally, the role of irrigation in almond responses to the almond replant problem is being investigated. Data from this project has shown that water management during the year of planting is essential to minimize negative effects of lack of fumigation. Objective 3- The results from these trials has been reported at the Annual Almond Industry Conference in Modesto, the Walnut Conference in Bodega Bay, Nickels Field Day, an annual grower field day at the site, as well as numerous farm advisor winter and summer field meetings. Objective 4- These data are proving to be useful in evaluating relative productivity of new varieties, impacts of fumigation on canopy growth as well as productivity per unit light intercepted, impacts of pruning and mechanical hedging on light interception and potential productivity, etc. What do you plan to do during the next reporting period to accomplish the goals? An iPhone app is currently being developed that will allow growers to estimate midday canopy light interception and hence yield potential in real time in the orchard. The iPhone app is planned for trials with farm advisors and select growers this summer.

PROGRESS:
2012/01/01 TO 2012/12/31
OUTPUTS: Objective 1- The goal of this aspect of the work is to determine if deficit irrigation and nitrogen management during the tree growth phase can result in a canopy structure that is more sustainable from a production and food safety point of view over time. Objective 2- This project was initiated to investigate the dynamics of spur renewal, fruitfulness and longevity and to determine how these are influenced by nitrogen and irrigation. Monitoring has been carried out for 9 years to quantify the impacts of treatments on spur longevity. In general, insect and disease susceptibility are directly related to water status with wetter trees tending to have more open shells and higher disease and insect damage. In the spring of 2008, all treatments were converted to the same nitrogen and water levels which aim for slightly lower levels of water and nitrogen compared to the original high water/high nitrogen treatments. Yields from 2008-2012 yields for the former deficit treatments are nearly equal to those in the high water, high nitrogen treatments after 4 years of similar levels of water and nitrogen application. Objective 3- The emphasis for this work has shifted somewhat and work is now studying the role of canopy management on food safety risk in almond. Work on stockpiling of almonds started in 2007 was continued through 2012. Results in 2008-2012 suggested that variability in canopy size across the orchard resulted in significant differences in moisture content of hulls and nuts such that more mold grew on nuts from the more heavily canopied parts of the orchard. In addition, work is underway evaluating the impact of different types of tarps used during stockpiling on temperature fluctuations and food safety risk. Finally, the role of irrigation in almond responses to the almond replant problem is being investigated. Data from this project has shown that water management during the year of planting is essential to minimize negative effects of lack of fumigation. Objective 4. Over eight years, unpruned Howard walnut trees have had equivalent yields, canopy height growth and midday canopy light interception compared to traditionally pruned trees. A second pruned versus unpruned trial was started in 2009 and results through the 2012 season again show no benefits of pruning. The results from these trials has been reported at the Annual Almond Industry Conference in Modesto, the Walnut Conference in Bodega Bay, Nickels Field Day, an annual grower field day at the site, as well as numerous farm advisor winter and summer field meetings. Objective 5. The mobile platform was used extensively during the 2009-2012 seasons to map midday light interception in 19 almond orchards and 18 walnut orchards. Yield data was then collected from the same plots in each orchard and these data are being used to refine the relationship between light interception and yield in these crops. These data are proving to be useful in evaluating relative productivity of new varieties, impacts of fumigation on canopy growth as well as productivity per unit light intercepted, impacts of pruning and mechanical hedging on light interception and potential productivity, etc. PARTICIPANTS: Dr. Greg Browne Plant Pathology - CAES One Shields Avenue Plant Pathology 354 Hutchison Hall Davis, CA 95616-8680 (530) 754-9351 Fax: (530) 752-5674 Bob Curtis, Research Director The Almond Board of California 1150 Ninth Street, Suite 1500 Modesto, CA 95354 Dr. Ted DeJong Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Dr. Kenneth Shackel Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 John Edstrom UCCE Colusa County PO Box 180, 100 Sunrise Boulevard Suite E Colusa, CA 95932 (530) 458-0570 Fax: (530) 458-4625 Rachel Elkins UCCE Lake County Ag Center, 883 Lakeport Blvd. Lakeport, CA 95453 (707) 263-6838 Dr. Tom Gradziel Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Joe Grant UCCE San Joaquin County 2101 E. Earhart Ave., Suite 200 Stockton, CA 95206 (209) 953-6100 Fax: (209) 953-6128 Janine Hasey UCCE Yuba/Sutter Counties 142 Garden Highway County Agricultural Building Suite A Yuba City, CA 95991-5512 (530) 822-7515 Fax: (530) 673-5368 Dr. Brent Holtz County Director UCCE San Joaquin County 2101 E. Earhart Ave., Suite 200 Stockton, CA 95206 (209) 953-6100 Fax: (209) 953-6128 Dr. Gale McGranahan Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Dr. Joe McIlvaine Paramount Farming Company 33141 E. Lerdo Highway Bakersfield, CA 93308 Dr. Themis Michailides Dept. of Plant Pathology UC Davis Kearney Agricultural Center 9240 S. Riverbend Ave. Kearney Ag. Center Parlier, CA 93648 Dr. David Ramos, Research Director California Walnut Board 101 Parkshore Drive, Suite 250 Folsom, CA 95630 Phone: (916) 932-7070 Fax: (916) 932-7071 Dr. Shrini Upadhyaya Dept. of Biological and Agricultural Engineering University of California Davis, CA 95616 Dr. David Slaughter Dept. of Biological and Agricultural Engineering University of California Davis, CA 95616.
TARGET AUDIENCES: The target audiences for this project have included farm advisors, PCAs, and growers throughout the state of California. Talks have been given related to this project for at least 6-8 annual grower winter meetings and 4-5 annual grower field meetings as well as at the annual walnut and almond meetings. PROJECT MODIFICATIONS: Not relevant to this project.

PROGRESS:
2011/01/01 TO 2011/12/31
OUTPUTS: Objective 1- The goal of this aspect of the work is to determine if deficit irrigation and nitrogen management during the tree growth phase can result in a canopy structure that is more sustainable from a production and food safety point of view over time. Objective 2- This project was initiated to investigate the dynamics of spur renewal, fruitfulness and longevity and to determine how these are influenced by nitrogen and irrigation. Monitoring has been carried out for 9 years to quantify the impacts of treatments on spur longevity. In general, insect and disease susceptibility are directly related to water status with wetter trees tending to have more open shells and higher disease and insect damage. In the spring of 2008, all treatments were converted to the same nitrogen and water levels which aim for slightly lower levels of water and nitrogen compared to the original high water/high nitrogen treatments. Yields from 2008-2011 yields for the former deficit treatments are nearly equal to those in the high water, high nitrogen treatments after 3 years of similar levels of water and nitrogen application. Objective 3- The emphasis for this work has shifted somewhat and work is now studying the role of canopy management on food safety risk in almond. Work on stockpiling of almonds started in 2007 was continued through 2011. Results in 2008-2011 suggested that variability in canopy size across the orchard resulted in significant differences in moisture content of hulls and nuts such that more mold grew on nuts from the more heavily canopied parts of the orchard. In addition, work is underway evaluating the impact of different types of tarps used during stockpiling on temperature fluctuations and food safety risk. Finally, the role of irrigation in almond responses to the almond replant problem is being investigated. Data from this project has shown that water management during the year of planting is essential to minimize negative effects of lack of fumigation. Objective 4. Over eight years, unpruned Howard walnut trees have had equivalent yields, canopy height growth and midday canopy light interception compared to traditionally pruned trees. A second pruned versus unpruned trial was started in 2009 with similar results to those from the earlier described Howard trial showing no benefits of pruning. The results from these trials has been reported at the Annual Almond Industry Conference in Modesto, the Walnut Conference in Bodega Bay, Nickels Field Day, as well as numerous farm advisor winter and summer field meetings. Objective 5. The mobile platform was used extensively during the 2009 and 2010 seasons to map midday light interception in 19 almond orchards and 18 walnut orchards. Yield data was then collected from the same plots in each orchard and these data are being used to refine the relationship between light interception and yield in these crops. These data are proving to be useful in evaluating relative productivity of new varieties, impacts of fumigation on canopy growth as well as productivity per unit light intercepted, impacts of pruning and mechanical hedging on light interception and potential productivity, etc. PARTICIPANTS: Dr. Greg Browne Plant Pathology - CAES One Shields Avenue Plant Pathology 354 Hutchison Hall Davis, CA 95616-8680 (530) 754-9351 Fax: (530) 752-5674 Bob Curtis, Research Director The Almond Board of California 1150 Ninth Street, Suite 1500 Modesto, CA 95354 Dr. Ted DeJong Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Dr. Kenneth Shackel Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 John Edstrom UCCE Colusa County PO Box 180, 100 Sunrise Boulevard Suite E Colusa, CA 95932 (530) 458-0570 Fax: (530) 458-4625 Rachel Elkins UCCE Lake County Ag Center, 883 Lakeport Blvd. Lakeport, CA 95453 (707) 263-6838 Dr. Tom Gradziel Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Joe Grant UCCE San Joaquin County 2101 E. Earhart Ave., Suite 200 Stockton, CA 95206 (209) 953-6100 Fax: (209) 953-6128 Janine Hasey UCCE Yuba/Sutter Counties 142 Garden Highway County Agricultural Building Suite A Yuba City, CA 95991-5512 (530) 822-7515 Fax: (530) 673-5368 Dr. Brent Holtz County Director UCCE San Joaquin County 2101 E. Earhart Ave., Suite 200 Stockton, CA 95206 (209) 953-6100 Fax: (209) 953-6128 Dr. Gale McGranahan Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Dr. Joe McIlvaine Paramount Farming Company 33141 E. Lerdo Highway Bakersfield, CA 93308 Dr. Themis Michailides Dept. of Plant Pathology UC Davis Kearney Agricultural Center 9240 S. Riverbend Ave. Kearney Ag. Center Parlier, CA 93648 Dr. David Ramos, Research Director California Walnut Board 101 Parkshore Drive, Suite 250 Folsom, CA 95630 Phone: (916) 932-7070 Fax: (916) 932-7071 Dr. Shrini Upadhyaya Dept. of Biological and Agricultural Engineering University of California Davis, CA 95616 Dr. David Slaughter Dept. of Biological and Agricultural Engineering University of California Davis, CA 95616.
TARGET AUDIENCES: The target audiences for this project have included farm advisors, PCAs, and growers throughout the state of California. Talks have been given related to this project for at least 6-8 annual grower winter meetings and 4-5 annual grower field meetings as well as at the annual walnut and almond meetings. PROJECT MODIFICATIONS: Not relevant to this project.

PROGRESS:
2010/01/01 TO 2010/12/31
OUTPUTS: Objective 1- The goal of this aspect of the work is to determine if deficit irrigation and nitrogen management during the tree growth phase (when canopy is filling in) can result in a canopy structure that is more sustainable from a production and food safety point of view over time. Objective 2- This project was initiated to investigate the dynamics of spur renewal, fruitfulness and longevity and to determine how these are influenced by nitrogen and irrigation. Monitoring has been carried out for 9 years to quantify the impacts of treatments on spur longevity. In general, insect and disease susceptibility are directly related to water status with wetter trees tending to have more open shells and higher disease and insect damage. In the spring of 2008, all treatments were converted to the same nitrogen and water levels which aim for slightly lower levels of water and nitrogen compared to the original high water/high nitrogen treatments. Results in 2008-2010 suggest that yields in the former deficit treatments are nearly equal to those in the high water, high nitrogen treatments after conversion to equivalent water and nitrogen regimes. Objective 3- The emphasis for this work has shifted somewhat and work is now studying the role of canopy management on food safety risk in almond. Work on stockpiling of almonds started in 2007 was continued through 2010. Results in 2008-2010 suggested that variability in canopy size across the orchard resulted in significant differences in moisture content of hulls and nuts such that more mold grew on nuts from the more heavily canopied parts of the orchard. In addition, work is underway evaluating the impact of different types of tarps used during stockpiling on temperature fluctuations and food safety risk. Finally, the role of irrigation in almond responses to the almond replant problem is being investigated. Data from this project has shown that water management during the year of planting is essential to minimize negative effects of lack of fumigation. Data collection is continuing on the longer term impacts of water management on canopy growth and productivity. Objective 4. Over eight years, unpruned Howard walnut trees have had equivalent yields, canopy height growth and midday canopy light interception compared to traditionally pruned trees. The results from these trials has been reported at the Annual Almond Industry Conference in Modesto, the Walnut Conference in Bodega Bay, Nickels Field Day, as well as numerous farm advisor meetings (both winter indoor and summer field meetings). Objective 5. The mobile platform was used extensively during the 2009 and 2010 seasons to map midday light interception in 19 almond orchards and 18 walnut orchards. Yield data was then collected from the same plots in each orchard and these data are being used to refine the relationship between light interception and yield in these crops. These data are proving to be useful in evaluating relative productivity of new varieties, impacts of fumigation on canopy growth as well as productivity per unit light intercepted, impacts of pruning and mechanical hedging on light interception and potential productivity, etc PARTICIPANTS: Dr. Greg Browne Plant Pathology - CAES One Shields Avenue Plant Pathology 354 Hutchison Hall Davis, CA 95616-8680 (530) 754-9351 Fax: (530) 752-5674 Bob Curtis, Research Director The Almond Board of California 1150 Ninth Street, Suite 1500 Modesto, CA 95354 Dr. Ted DeJong Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Dr. Kenneth Shackel Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 John Edstrom UCCE Colusa County PO Box 180, 100 Sunrise Boulevard Suite E Colusa, CA 95932 (530) 458-0570 Fax: (530) 458-4625 Rachel Elkins UCCE Lake County Ag Center, 883 Lakeport Blvd. Lakeport, CA 95453 (707) 263-6838 Dr. Tom Gradziel Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Joe Grant UCCE San Joaquin County 2101 E. Earhart Ave., Suite 200 Stockton, CA 95206 (209) 953-6100 Fax: (209) 953-6128 Janine Hasey UCCE Yuba/Sutter Counties 142 Garden Highway County Agricultural Building Suite A Yuba City, CA 95991-5512 (530) 822-7515 Fax: (530) 673-5368 Dr. Brent Holtz County Director UCCE San Joaquin County 2101 E. Earhart Ave., Suite 200 Stockton, CA 95206 (209) 953-6100 Fax: (209) 953-6128 Dr. Gale McGranahan Dept. of Plant Sciences Mail Stop #2, Dept. of Plant Sciences University of California Davis, CA 95616 Dr. Joe McIlvaine Paramount Farming Company 33141 E. Lerdo Highway Bakersfield, CA 93308 Dr. Themis Michailides Dept. of Plant Pathology UC Davis Kearney Agricultural Center 9240 S. Riverbend Ave. Kearney Ag. Center Parlier, CA 93648 Dr. David Ramos, Research Director California Walnut Board 101 Parkshore Drive, Suite 250 Folsom, CA 95630 Phone: (916) 932-7070 Fax: (916) 932-7071 Dr. Shrini Upadhyaya Dept. of Biological and Agricultural Engineering University of California Davis, CA 95616 Dr. David Slaughter Dept. of Biological and Agricultural Engineering University of California Davis, CA 95616.
TARGET AUDIENCES: The target audiences for this project have included farm advisors, PCAs, and growers throughout the state of California. Talks have been given related to this project for at least 6-8 annual grower winter meetings and 4-5 annual grower field meetings as well as at the annual walnut and almond meetings. PROJECT MODIFICATIONS: Not relevant to this project.

Funding Source
Nat'l. Inst. of Food and Agriculture
Project source
View this project
Project number
CA-D-PLS-6885-H
Accession number
188866
Categories
Pesticide Residues
Parasites
Natural Toxins
Viruses and Prions
Bacterial Pathogens
Chemical Contaminants
Commodities
Nuts, Seeds