Last month I told you part of the story about the chemophobic residents of north central California and the impact they had on pesticide/pheromone use against the light brown apple moth (LBAM). Now, with the recent find of a single male moth in the Bonsall area of North County, it makes sense to spend some time and discuss the moth itself. A complimentary article about the regulations accompanying that find is being written by Jan Hall and can be found in this newsletter.

Like many well-known serious insect pests across the world, LBAM is feared by countries that do not have the pest, yet have a serious investment in agriculture. Therefore, our 'trading partners' determine how San Diego County will act to an infestation of this nature; it is being taken very seriously. California considers LBAM to be an 'A' rated pest, which are pests of known economic importance that are subject to state enforced action that includes eradication, quarantine regulation, containment, rejection, or other holding action.

The majority of LBAM detections in California have been in production and retail nurseries located near urban areas. Since nursery stock is shipped intra and interstate, it is easy for LBAM and other pests to be moved along with the nursery stock. Therefore, most of the regulatory action falls on ornamental plant producers. Retail nurseries are under the same regulations. However, retail nurseries are not prepared for widespread application of a pesticide as mandated, and will most likely have to hire a commercial pest control applicator. Retail nurseries will also have to follow the label and the restricted entry period, and must be inspected and found free of LBAM.

I don't want to overburden everyone with all the particulars on the biology of LBAM, so I just chose a few of the highlights. The light brown apple moth, Epiphyas postvittana, is a tortricid leafroller moth native to Australia, but has established in New Zealand, New Caledonia, Great Britain, Ireland, and Hawaii. The caterpillar feeds on over 2,000 different plant species in about 50 plant families. When a pest feeds on that many different plants it is called polyphagous and most certainly includes a great number of ornamental plants. It is almost easier to list plants that are not hosts. LBAM larvae are known to feed directly on the fruit and buds of grapes, apples, kiwi, plums, avocados, and citrus, which significantly reduces marketability. Because there can be serious damage to a great number of agricultural commodities, there is a zero tolerance for the presence of LBAM in any shipment of plant products. Unfortunately, that means ornamentals for sure, and just about anything that is plant based is regulated for the presence of LBAM including cut crops and wreaths.

LBAM will most likely have 3 or 4 overlapping generations a year in southern California, and it does not diapause in winter, which means it will continue population growth year round. The pupal stage lasts several weeks and takes place in a rolled up leaf as the name (leafroller) suggests. The pupal stage lasts 1 to 3 weeks, and adults mate soon after emergence. Moths typically fly 2 to 3 hours after sunset and before daybreak. Females begin to lay eggs 2 to 3 days after emergence and continue to lay eggs for about 21 days. Female LBAM deposit their eggs in a batch (120-500) rather than singly, and they lay them on smooth leaf surfaces usually near the midvein. Eggs hatch in about a week at 80°F. Larval development can take from 3 to 8 weeks, depending on temperature.

LBAM is monitored and can be controlled using a pheromone, which attracts the male moth and disrupts mating. Much of this research on pheromone use has been completed in Australia, where the moth originates and is a serious pest.

If you suspect that you have an LBAM larva, you should take it to the agricultural commissioner's office, and if possible, bring the live larvae inside the webbed nests of rolled-up leaves, flowers, or fruit clusters. The county has been trapping for adults using the pheromone at a rate of one trap every 5mile² ever since the bug got into the central coast of California. It seemed inevitable that the moth would make it to San Diego County in one way or another.

At the moment, mating disruption using pheromones is the eradication method of choice by inundating an area with pheromone impregnated twist ties, which have been show to work very well in Australia. There is a concerted effort, however, to develop a sterile insect technique against this pest like the one used for the Medfly. It's not far off.

On an additional note, everyone should be aware that the USDA is running the show here because this is a 'federal bug', so to speak. Therefore, if a quarantine is declared due to another moth find, the entire county is under quarantine. Bob Atkins (Ag commissioner) and the Farm Bureau are making an effort to limit the scope of the quarantine in San Diego County. To require the entire county in all its breath and width and diversity to begin trapping and treating with pesticides is not practical or common sense. Then again... it is the government.

Don't forget about the Annual California Spring Trials (Formerly called Pack Trials) which is taking place April 10-17th.  Members of SDCFPA who are participating with displays are EuroAmerican Propagators, The Plug Connection, Ball Horticultural, Paul Ecke Ranch, Booman Floral, Master Tag, Jiffy Products and John Henry.  Please help support your fellow members by attending this fabulous event!  For more information go to:

http://www.ngb.org/spring_trials/index.cfm

http://www.ballpublishing.com/GrowerTalks/_SpringTrialsPlanner.aspx