Research and IPM

From the 2007 UC IPM Demonstration Grants Program—New residential IPM approaches to manage codling moth

• Daniel B. Marcum, UCCE, Shasta/Lassen counties
• Alan Knight, USDA-ARS
• Carolyn Pickel, UCCE/IPM, Sutter-Yuba counties

Scientists have discovered a chemical in pears that has just the right scent to attract codling moths to traps. This discovery is part of a larger UC program to control codling moth pests in homeowners' backyard trees.

The urban area-wide project has a multi-pronged approach to controlling codling moth, including better cultural practices like pruning, trapping females and males with new lures and traps, using a granulosis virus and insect-feeding nematodes applied in the spring and fall. The new lures attracts both sexes and contains a novel chemical called pear ester that has the natural taste of Bartlett pears used in pear-flavored jellybeans.

Through the Selective Organic Fruit Tree (SOFT) program, scientists hope to give homeowners an effective program using certified-organic approved methods to produce worm-free fruit and nuts in backyards. In turn, reduction of moths in backyard trees can reduce pests migrating into commercial orchards, a growing concern with encroachment of suburban developments into agricultural areas.

Application of IPM practices to Trinity County's heritage and backyard orchards

• Gary Nakamura, UCCE, Shasta/Trinity counties
• Carol Fall, UCCE, Trinity County

Trinity County has a substantial number of heritage fruit orchards, dating from the gold mining era through World War I, on public and private lands. UCCE Trinity's Heritage Orchard Project has been inventorying these trees and using this unique asset to promote use of these heirloom fruit orchards as a food resource, demonstrate techniques to care for and increase production from these fruit trees, provide a focal point for agritourism and value-added product marketing, and preserve a vanishing horticultural heritage.

In 2007, researchers held three well-attended workshops on fruit tree care and pruning, using the 80-year-old apple and pear trees at Lee Fong Park as a demonstration site.

Trinity County has an ordinance prohibiting the use of pesticides on public lands that precludes application of carbaryl. As a result, the team promotes sanitation, traps, and spinosad sprays. Reinforcement of pruning techniques complements and enhances the effectiveness of other IPM practices such as Selective Organic Fruit Tree treatments.

Demonstration garden promotes best IPM practices

• Ken R. Churches and Karen Riley, UCCE, Calaveras County

The Calaveras County Demonstration Garden offers up-to-date information and demonstrates good growing and IPM practices. Hands-on workshops in the garden give the public practice using IPM techniques.

Master Gardeners developed the Demonstration Garden as a teaching tool. They are installing and maintaining Quick Tip signs throughout the garden and a weather station, developing tours and seminars, and distributing UC IPM Quick Tips and other resources, besides posting data on the UCCE Web site. Visitors see IPM strategies in practice in garden beds and get Quick Tip cards to take home.

The Calaveras County Agriculture Department also uses the Garden to present seminars on invasive weeds, current county and state regulations, and best practices when using pesticides.

Improved adoption of IPM by nut crop PCAs and growers in the lower San Joaquin Valley

• David Haviland, UCCE, Kern County
• Bob Beede, UCCE, Kings/Tulare counties

With the expansion of almond and pistachio production in Kern County, the need for extension and demonstration projects about IPM practices related to these crops is vital. This need stems from the recent influx of PCAs required to oversee this vast nut crop acreage. Presently, most are versed in field crops such as cotton, alfalfa and corn, or perennials like grapes and citrus.

The purpose of this project is to provide almond and pistachio PCAs and growers in the lower San Joaquin Valley with opportunities to see IPM principles demonstrated in the field. This will improve their familiarity with the practices UC recommends in the UC IPM Pest Management Guidelines and Almond Year-Round IPM program.

Area-wide "puffer" demonstration in Tehama County

• Carolyn Pickel, UCCE/IPM, Sutter-Yuba counties
• Rick Buchner, UCCE, Tehama County

Codling moth is the primary target of broad-spectrum insecticides in walnuts, so adoption of alternative pest management technologies could greatly reduce growers' use of these insecticides.

The walnut Pest Management Alliance (PMA) has been working to develop a practical mating disruption program in walnuts using puffer pheromone dispensers. Research and long-term demonstrations in Butte and San Joaquin counties have begun to show success in using this technology to control codling moth in walnuts; in fact, mating disruption can reduce bad actor pesticide use from 50 to 75 percent depending on the population density in the block. Puffer dispensers provide the first effective and economic mating disruption program that is commercially available. This project expands the technology to promote adoption in Tehama County.

Demonstration of house fly IPM at commercial dairies

• Alec C. Gerry, Entomology, UC Riverside
• Gerald E. Higginbotham, UCCE, Fresno County
• Christian Shelton, Computer Science, UC Riverside

House flies are considered to be the number one nuisance pest associated with dairy and other confined animal operations. These flies are also capable of carrying a number of disease organisms that affect humans and animals such as the virulent Escherichia coli strain. The presence of house flies is especially problematic in urban or semi-urban areas bordering agricultural areas containing animal agriculture.

This project demonstrates to large dairy operators the value of an automated spot card monitoring system as part of an IPM program for house flies. Using the automated system, operators can quickly measure fly abundance and take action based upon proportional increases in fly abundance, using early intervention measures and avoiding the need for later chemical applications, while reducing outbreaks of nuisance and disease-carrying house flies.

Demonstrating the use of silicon and other IPM practices to reduce pesticide applications in bedding plant operations

• Julie Newman, UCCE, Ventura/Santa Barbara counties
• Cheryl Wilen, UCCE/IPM, San Diego County
• James Bethke, UCCE, San Diego County

Production of annual bedding plants, garden plants, and propagation materials in California exceeded more than $364 million in 2006. Typical plants include begonias, geraniums, impatiens, New Guinea impatiens, marigold, pansy/viola, and petunias.

This industry is characterized by very rapid plant production, usually going from seed to finished plant in four to six weeks. IPM practices taken for granted in much of California agriculture are not practiced by many growers. Because of the short turnaround time, biological control with predators and parasites is severely handicapped, and many of these growers rely on pesticides to assure that the plants are pest-free.

Adding silicon to fertilizer mix can enhance bedding plant resistance to pests and increase tolerance to pest damage, reducing overall pest population development. Project leaders are demonstrating the technique at four California sites to increase its use by growers.

Management of corn leafhopper and corn stunt disease in corn

• Charles Summers, Entomology, UC Davis, Kearney Agric. Center
• Carol Frate, UCCE, Tulare County
• Shannon Mueller, UCCE, Fresno County
• Tulio Macedo, UCCE, Madera County
• Mick Canevari, UCCE, San Joaquin County
• Marsha Campbell-Mathews,UCCE, Stanislaus County
• Kent Brittan, UCCE, Yolo County

In addition to yield losses caused by feeding injury, corn leafhopper is a vector of the corn stunt spiroplasma, Spiroplasma kunkelii, the cause of corn stunt disease. Infection with the disease can result in even more significant yield losses than those attributable to leafhopper feeding alone. Southern San Joaquin Valley is hit with corn leafhopper and corn stunt disease every year. Damage is most severe on corn harvested late in the season (from September on). Severely infected corn has a significantly lower nutrient value and many dairies refuse to accept it.

Winter cereal species serve as bridge hosts to help carry adult leafhoppers through the winter. Planting successive corn crops is a dangerous practice because the large number of spring volunteer corn plants may carry the corn stunt spiroplasma and serve as a ready in-field source of disease inoculum.

This project aims to teach growers and PCAs how to sample for corn leafhopper and stunt-diseased plants, and how to properly make decisions about the need, or the lack of need, for pesticide treatments.

Demonstration of efficacy of postharvest ethephon in the suppression of overwintering codling moth in pears

• Robert Van Steenwyk, ESPM, UC Berkeley
• Chuck Ingels, UCCE, Sacramento County
• Lucia Varela, UCCE/IPM, Sonoma County

Codling moth is the key insect pest of pears. In the past, control of the pest has relied on repeated applications of some insecticides. Pear codling moth management now relies on mating disruption and supplemental insecticides to maintain a low population. Codling moth pheromone control has been demonstrated to be effective under very low population pressure, but several supplemental insecticide applications may be required to maintain this low population. The supplemental insecticides may cause a substantial increase in secondary pests which are usually held under control by beneficial arthropods with a minimal need for sprays.

Use of the plant growth regulator Ethephon is an environmentally benign method to supplement mating disruption. Its application shortly after harvest promotes early ripening and fruit drop. If the fruit remaining in the orchards after harvest can be induced to ripen rapidly, then codling moth overwintering population can be largely eliminated without the use of insecticides.

This project demonstrates to pear growers the long-term effectiveness of a postharvest codling moth suppression program on pears using Ethephon 2SL on codling moth populations and rattail fruit production.