Pests Which Affect Green Material Movement in California

More than 76,000 farms and ranches in California produce more than 400 different crops worth more than $50 billion annually, the most of any State. Fully one third of the nation’s vegetables and two thirds of its fruits and nuts are produced here. Unfortunately, this prosperity is threatened by an increasingly large and varied group of imported pests which carry tree-killing diseases or render fruits and vegetables inedible. Some of these pests threaten agriculture, while others attack iconic native species. To prevent or slow the spread of pests, local, federal and state agriculture officials conduct trapping, eradicate pests when found, and enforce quarantines.

Agricultural officials have the power to restrict the movement of green materials. They may prohibit materials from leaving the quarantine zone, or may attach conditions to ensure pests do not move along with restricted materials, which could include green materials or food wastes. Every entity in the chain of custody for handling green materials from a quarantine zone, including haulers, transfer stations, chip-and-grind facilities, composting facilities or landfills, must have the appropriate compliance agreements in place in order to handle these materials. There is no cost for obtaining a compliance agreement; however, there may be costs inherent in compliance. Compliance agreements are obtained from each county’s Agricultural Commissioner’s office, and they set the terms for movement and handling of quarantined materials.

Movement of materials out of quarantine zones, particularly if these materials are spread on agricultural land without being composted, can spread pests and disease. Such movement is also illegal, and can carry significant penalties. Be sure to contact your County Agricultural Commissioner to obtain a compliance agreement if you are handling green materials which come from any active quarantine zone.

Current Quarantines of Concern to Green Material Handlers

Pest of Concern

Invasive Polyphagous Shot Hole Borer (PSHB). PSHB is an invasive beetle that attacks a wide range of trees in California, including commercial avocado groves, oaks, sycamores, and hundreds of other landscape trees. PSHB spread a disease called Fusarium Dieback that is caused by a type of fungus. Even though there is no quarantine for this pest yet, green material handlers should learn to recognize PSHB, Kirushio Shot Hole Borers, and the symptoms of Fusarium Dieback.

Pest Profiles

Asian Citrus Psyllid (ACP) is an aphid-like insect that feeds on the leaves and stems of citrus trees and other citrus-like plants and can be a carrier of a deadly bacterial tree disease called Huanglongbing, or “Citrus Greening Disease.” The disease kills citrus trees within a few years following transmission and poses a significant threat to California’s citrus industry.

European Grapevine Moth is found in southern Asia, Europe, North Africa, Anatolia, Caucasus and South America. The pest primarily damages grapes, but has also feeds on various crops and plants.

Light Brown Apple Moth is an insect native to Australia. It is a pest of concern because it feeds on agricultural produce and damages a wide variety of plants (more than 2,000 species). Some of the plants it affects are roses, chrysanthemums, jasmine, and clover, as well as eucalyptus, poplar, and pine trees.

Sudden Oak Death is a disease that has caused the death of large numbers of oaks and tanoaks, mostly in the coastal counties of California. In recent years, the cause was identified as a new plant pathogen, Phytophthora ramorum. Many species of nursery stock are now known to be susceptible to Phytophthora ramorum.

Fruit Flies (GuavaMalaysianMediterraneanMelon, and Oriental). All fruit flies damage dozens or even hundreds of different types of fruits and vegetables, rendering them unsalable and often inedible. With fruit flies, the quarantined material is generally fruit or vegetables and soil under the drip line of the tree.  Green material movement is not affected.

Pesticide/Herbicide Residues in Compost

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