- Cool-Season Grass
- Cool-Season Vegetable Crops
- Dry Beans
- Field Corn
- Invasive Pests
Alfalfa is one of the most commonly grown crops in California. It is grown statewide but varies tremendously in pest severity and management styles across the state. The alfalfa weevil is one of the most severe pests and management of this pest with insecticides has created significant environmental problems due to pesticide runoff into waterways. New pests (cowpea aphid) and increased severity of Lepidopterious pests (beet and western yellow striped armyworms) and blue alfalfa aphids are also issues in alfalfa. One of the areas most severely affected by these challenges is near the Davis campus so research opportunities abound. Click on here or on link for more details.
Cool-Season Grass Hay Crops
Cool-season grasses are grown as a source of high-quality hay for the horse industry (commercial and hobbyist) and for export. Timothy is the primary species used but orchard grass and others are also produced. Timothy hay and pellets are also used for rabbit hobbyists. These types of grasses are typically grown in cooler areas as opposed to alfalfa which can flourish and be produced in hot areas. Cool-season hay values are highly dependent on aesthetic appearance of the hay whereas alfalfa hay nutrient quality is very important. IPM programs were developed for timothy hay crops through a 5-yr. research project. Grass thrips and spider mites were the primary pests identified and management tactics were developed and delivered to growers. More details are here.
Cool-Season Vegetable Crops
The Salinas Valley (Monterey Co.) and nearby associated coastal production areas are rather unique agricultural areas in California and the U.S. The environment of these areas is heavily marine-influenced and as such is ideal for the production of cool-season vegetables, strawberries, cane berries, etc. These high value crops for the U.S and export markets must be extremely high quality and are produced year-around. The moderate climatic conditions, constant crop production, significant agricultural "traffic", and high degree of tourism and human movement stress IPM programs to the maximum. Ongoing research efforts are needed to mitigate these issues. Click on link to left for more details.
Cotton is damaged by several insect and mite pests from the seedling stage until harvest. There is a huge database of production and IPM information on cotton and active cotton IPM research programs across the southern tier of states (from Arizona to Virginia); there is significant information on which to build. My research in recent years has focused on the western tarnished plant bug, spider mites, sweetpotato whiteflies, and cotton aphids in cotton (more details)(Shafter Research Laboratory).
Dry beans represent a large diversity of types, production strategies, pest pressure, etc. Overall, beans are one of the food staples world-wide. In California, several types of high value specialty beans are grown including black-eye cowpeas, garbanzos, and baby limas. Appearance/quality of these beans is very important and the western tarnished plant bug, Lygus hesperus, is one of the important pests. Cultural and biological controls provide some management of this pest but until recently, insecticides were the method of choice. Recently, a vine baby lima variety has been developed with a level of host plant resistance to lygus bugs.
• Development of an IPM program incorporating host plant resistance and reduced risk insecticides for lygus bug managment. A variety of vine baby lima bean has been developed with a usable level of tolerance to this key pest.
• Lygus bug sampling using the standard sweep net method and action threshold on vine baby lima beans.
On average, in six new species establish in California each year with economic loses to California from invasive species estimated at $3 billion per year. The unique climate and geography of the state provide diverse ecosytems which are perfect for the establishment of a diverse variety of new pests. The high amount of interstate and international travel, importation of trade items, etc. also contribute to the movement of invasive species. Research, regulatory, and extension personnel are all involved in attempting to deal with these species. More details are here.
In response to pest population build-up and melon industry concerns, the biology and management of cucumber beetles have been examined. Two species of cucumber, western spotted cucumber beetle (Diabrotica undecimpunctata undecimpunctata) and western striped cucumber beetle (Acalymma trivittatum) beetles feed on melon foliage and on the developing melons. The damage to the fruit renders it useless for the export market. The last published report on the biology of these pests from California was from the 1940’s. Our studies showed changes in the agricultural landscape were likely responsible for build-up of this pest.
Mint is a small acreage crop grown in northern California near the Oregon border and in the Intermountain area. These are some of the most beautiful and environmentally sensitive areas of the state with pristine stream and nature preserves. Peppermint oil is used as flavoring for toothpaste, chewing gum, and other confectionery items and as insect repellent, aromatherapy, and mint teas. Mint oil is critiqued by experts with many similarities to the scrutiny given to fine wines. Specific qualities/components of the oil are important for various end-uses. Spider mite management with the use of predatory mites and mint root borer biology, use of degree-day models, reduced risk insecticides and mating disruption, are among the areas being investigated.
Thrips are a significant pest of onions nationwide. A recent pest management challenge to onion production is Iris yellow spot virus which is vectored by Onion Thrips, Thrips tabaci. My lab is involved in a cooperative project on managing thrips on onions in northern California. This area presents some unique challenges compared with other onion production areas in the U.S. and in California (onion production occurs across the state) in that both onion thrips and western flower thrips, Frankliniella occidentalis, occur and at this point iris yellow spot virus is not present.
Yes, there is rice grown in California – ~600,000 acres worth ~$1.3 billion annually. Rice is utilized by >230 species of wildlife with ~31 listed as species of special concern. Almost all sushi rice in the U.S. is grown in California.
Management of the most important rice insect pest, the rice water weevil, depends on the use of reduced risk insecticides and non-chemical methods. Rice fields are connected to the Sacramento River waterway and ultimately to the San Francisco Bay waters. Therefore, environmental consequences of management activities are closely scrutinized. Ecological studies on rice water weevil – an aerobic animal (larva) that feeds on rice roots within the flooded soil have been a priority of the lab.
A second priority has been to design rice production and management schemes that maximize rice production while minimizing production of pestiferous mosquito populations.
In recent years, the tadpole shrimp has emerged as a significant pest of rice. Research is ongoing on this pest.
Invasive pests are a constant challenge in rice - this is maximized given the global nature of the crop. An infestation of panicle rice mite, Steneotarsonemus spinki Smiley, was found and eradicated in the greenhouses on the UC-Davis campus. Infestations of this pest were not found in any grower fields.
Graduate students, post-doctoral research associates, and staff research associates have contributed greatly to this 20+ year research effort on rice IPM. More details here.