Department of Botany & Plant Sciences

Cooperative Extension


As a land-grant institution, the University of California Cooperative Extension (CE) specialists are dedicated to the welfare, development and protection of California agriculture and are the outreach arm the University of California’s Agricultural and Natural Resources program. CE specialists are headquartered at UC Riverside, UC Davis and UC Berkeley and provide statewide leadership to farm advisors and faculty, and carry out outreach programs at the state and local level. CE specialists perform both basic and applied research and thereby are a critical link in the research continuum that addresses problems that are encountered in California agriculture. On May 2014, CE will celebrate 100 years of service to California and a brief history can be found at http://cesonoma.ucanr.edu/100_Year_Anniversary/History/. Useful links are also provided below.

The UC Riverside CE specialists provide a wide range of expertise focusing on over 100 crops and issues in conservation biology, the environment, organic agriculture, postharvest physiology, and agricultural biotechnology. Our CE faculty and areas of expertise and useful links are provided below.

Edith Allen

ALLEN, Edith B.

Professor of Plant Ecology; Cooperative Extension Specialist in Conservation Biology; Department Vice Chair


Effects of invasive species on native vegetation, weed competition and succession, restoration ecology and mycorrhizal fungi, effects of urbanization and agriculture on native ecosystems

Mary Lu Arpaia


CE Subtropical Horticulturist


Cooperative Extension Specialist - Evaluation of preharvest and postharvest factors on subtropical crop productivity and fruit quality, including rootstocks, cultivar, irrigation, pesticide, and nutrition management strategies
James Baird

BAIRD, James

CE Assistant Turfgrass Specialist


Turfgrass variety improvement and selection, plant stress physiology related to temperature and water, and natural resource concerns, including water allocation and management, energy conservation, atmospheric quality or other issues at the intersection of Turfgrass landscapes with native and production agricultural areas.
Peggy Mauk

MAUK, Peggy

CE Specialist for Subtropical Crops/Ag Ops Director


Evaluation of avocado rootstocks for salinity tolerance. Research on abiotic or biotic stresses of subtropical fruit crops, such as avocado, citrus, dates and mangos. Director of Agricultural Operations (www.agops.ucr.edu), which oversees field research in support of the mission of the College of Agriculture and Natural Sciences.

Milton McGiffen

McGIFFEN, Milton E.

CE Specialist - Vegetable Crops and Plant Physiology


Vegetable crops, organic agriculture, weed science, biochar, greenhouse gases, carbon sequestration and recycling, water and nutrients, environmental impact of agriculture.

Alan McHughen


CE Plant Biotechnologist


Cooperative Extension Specialist - Biotechnology for sustainable agriculture. Policy development and public education.
Donald Merhaut


CE Associate Specialist/Associate Horticulturist


Cooperative Extension Specialist-Nursery Floriculturist/Horticulturist
Philippe Rolshausen


CE Assistant Specialist & Assistant Horticulturist


Rolshaunsen's interests lie in identifying biotic and abiotic factors that limit fruit and nut crops productivity and to develop and implement sustainable strategies to improve the productivity in these crops.


Research and Extension Centers


Cross Commodity

Pest and Weed Management

Landscape and Nursery, Gardens

Agriculture Economic and Public Policy

More Information

General Campus Information

University of California, Riverside
900 University Ave.
Riverside, CA 92521
Tel: (951) 827-1012

Career OpportunitiesUCR Libraries
Campus StatusDirections to UCR

Department & Program Information

Department of Botany & Plant Sciences
2142 Batchelor Hall

Tel: (951) 827-4619
Fax: (951) 827-4437
E-mail: bpschair@ucr.edu

Plant Biology Graduate Program
CNAS Grad Student Affairs Office
1140 Batchelor Hall

Tel: (800) 735-0717
Fax: (951) 827-5688
E-mail: Laura.mcgeehan@ucr.edu