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Environmental Horticulture / Environmental Science

John Karlik 661-868-6220 jfkarlik@ucanr.edu

The goal of environmental horticulture is to preserve and enhance the environment through planting and proper cultural practices for green plants, including shade trees, shrubs, and turfgrass.  Environmental science includes preservation and enhancement of environmental quality of soil, water and air.  Kern County is a leader in the U.S. in production of rose plants for landscapes and home grounds.

Cooperative Extension provides information on turfgrass, plant selection, cultural practices, arboriculture, landscape maintenance, and pest management. 


Rose Rosette Disease Information

Rose Rosette Disease Demystified  

What is Rose Rosette Disease?

Managing Rose Rosette Disease in the Landscape


Updated  Shade and Ornamental Tree Guide for Kern County

This updated guide was revised and expanded in April 2017.  You can download the Guide here.


Updated Shrub and Groundcover Guide for Kern County

This updated guide was revised and expanded in August 2020.  You can download the Guide here.


Horticulture Classes for Landscapes, Gardens, and Orchards

We continue to offer a series of horticulture classes in Bakersfield and Kern County.  Our goals are to conserve water, to enhance and expand green plantings, and to reduce pesticide applications. We will cover practical topics pertaining to planting and care of landscapes, orchards, and vegetable gardens, and offer plenty of time for Q&A and discussion. We welcome individuals who have little horticulture experience, as well as those who work in some aspect of horticulture.  Please feel free to contact us for information, 661-868-6200 or jfkarlik@ucdavis.edu

(Additional note:Kern County does not offer the Master Gardener volunteer program at this time.  If you would like more information about that program in California, please refer to the website http://camastergardeners.ucdavis.edu/)


Horticulture Tours

I have offered several horticultural tours, and plan to continue this educational effort. Our heritage of landscape and garden design includes the rich tradition of gardens of several parts of the world, including Europe and the Mediterranean, and some of the world's most interesting and beautiful plant arrangements and collections may be found there. A number of gardens and landscapes exquisitely illustrate design principles and have withstood the test of time. These sights are well worth sharing.

The overall tour objective is to broaden participants' knowledge and appreciation for landscape design and plant selection. The tour also provides an opportunity to experience the flavor of specific countries. Group sizes have ranged from nine to twenty-six.


Past Horticulture Tours

2005 England (London environs) and France (Paris environs)

2006 Italy (Lago di Como, Florence, Rome, Pompeii)

2007 West-Central Europe (Netherlands, Berlin, Prague, Vienna)

2009 England and Scotland (northeast)

2010 Spain

2012 France and the Netherlands

2013 Ireland

2014 Scotland (northwest)

2017 Iceland

2019 Thailand and Cambodia


Research Projects

Green plants contribute volatile organic compounds (VOC) which can enter into atmospheric reactions that form ozone (a pollutant when found close to the Earth’s surface) and secondary organic aerosols. We have conducted a number of research projects pertaining to development of biogenic emission inventories, including measurement of plant VOC emission rates, leaf mass quantification, and evaluation of databases for plant species description.  This work also informs shade tree selection for mass planting programs to enhance air quality.

Green Scene Newsletter

The Green Scene is John Karlik's periodical publication that covers all things horticultural. Sign up today!

Green Scene May 2024
Green Scene April 2024
Green Scene March 2024
Green Scene February 2024
Green Scene January 2024