Holden's Instructors
Holden Staff Instructors
David Burke, PhD, holds a bachelor's degree in environmental science from Rutgers University, a master's degree biology from East Stroudsburg University and a doctorate in biology, with concentration in ecology and evolution, from Rutgers University. Burke is a plant biologist whose research focuses on the interactions between plant roots and soil organisms with a particular emphasis on mycorrhizal ecology. He is an assistant scientist at The Holden Arboretum and has an adjunct position in the Department of Biology at Case Western Reserve University.
Toby Davidson, horticulture supervisor for the Display Gardens, earned his associate's degree in forestry from Hocking College. He spent the first eight of his 12 years at Holden caring for the trees in the outer collections. He enjoys pruning trees and designing garden spaces.
Julie Dougherty, guest relations specialist. Doughterty is a certified interpretive guide from the National Association for Interpreters. She earned her bachelor's degree from Cleveland State University, her master's degree in sports psychology from West Virginia University and her master's in education administration from Ursuline College. She taught outdoor education at Hiram House Camp for 10 years, physical education at St. Vitus for 12 years and served as principal at St. Louis Elementary for seven years.
Viki Ferreniea, lead horticulturist at Holden was formerly director of horticulture for the New England Wildflower Society. Ferreniea, a graduate of Swanley Horticultural College in Kent, England, received the national diploma in horticulture from the Royal Horticulture Society. She trained at the Royal Botanical Gardens at Kew, England. She is the creator of the North American wildflower garden at Longwood Gardens near Philadelphia, Pa., and has lectured and taught about wildflowers all over the country. Ferreniea is the author of Wildflowers in Your Garden, published in 1993.
Roger Gettig, director of horticulture and conservation. Roger began his career at Holden in 1988 as a native plant intern before becoming full-time staff as natural areas foreman. He left Holden to attend the University of Wisconsin, where he majored in ecological restoration while earning his Master's degree in landscape architecture. He returned to Holden in 1996 as landscape consultant and then assumed the role of land conservation manager.
Lori Gogolin earned an associate's degree in horticulture from Kent State University in 1998. She is a horticulturist at The Holden Arboretum and is responsible for the Arlene and Arthur S. Holden Jr. Butterfly Garden.
Sharon Graper, manager of formal education, began her relationship with Holden in 1981 as a student at Hawken High School, working on her senior project in the Myrtle S. Holden Wildflower Garden. She came back as an intern in 1984 and as a summer employee teaching children’s classes in 1991. Since 1994, she has managed school and youth programming at Holden. She earned her undergraduate degree in environmental science from the University of Virginia and her master’s degree in science education from the University of Delaware.
Clement W. Hamilton, president and CEO. Hamilton grew up in Wisconsin and Ohio, where he developed his three primary passions for nature, baseball and music. He earned a bachelor's degree in geology at Harvard, and a doctorate in ecology and evolutionary biology at Washington University and the Missouri Botanical Garden. He has conducted botanical research and fieldwork in Thailand, Panama and Chile, as well as the United States. He was assistant and associate professor in the Center for Urban Horticulture at the University of Washington in 1985-99, directing the center in 1992-99; executive director of Rancho Santa Ana Botanic Garden in Claremont, Calif., in 1999-2004; and vice president for arboretum programs and director of research at the Morton Arboretum in Lisle, Ill., in 2004-08. In the spring of 2008, Hamilton became president and CEO of The Holden Arboretum, where he seeks to maximize Holden's contribution toward creating a more livable, diverse and ecologically sustainable world by promoting the planting and conservation of trees and forests.
Ethan Johnson, plant records curator, earned his associate's degree from Paul Smith’s College, N.Y., in forestry and his bachelor's degree in environmental horticulture from the University of Connecticut. He has been Holden’s plant records curator since 1989. As curator he documents the history, growth, phenology, and condition of cultivated plants in the living collection as well as produces plant accession, labels and collection maps.
Stephen Krebs, PhD, started at David G. Leach Research Station in 1992 and has been the director of the Leach Research Station since 1998. He received his bachelor's degree in history at the University of Chicago and his doctorate in plant breeding and genetics/horticulture from Michigan State University. Work at the Leach Station centers on the development of ornamental rhododendrons that are adapted to difficult conditions. Research in support of this goal includes investigations of cold and heat tolerance, identification and transfer of disease resistance, and adaptations to brighter (sunnier) growing conditions.
Kurt Smemo is an ecosystem ecologist at The Holden Arboretum and an adjunct assistant professor at Case Western Reserve University and Michigan State University. His studies involve how soil microorganisms control organic matter decomposition and nutrient availability in forest and wetland ecosystems, and how those organisms respond to environmental change. Smemo has earned his bachelor's degree in forestry at the University of Montana, his master's in environmental science at the University of Illinois and his doctorate in ecology from Cornell University.
Susan Swisher, Holden's librarian, is a Northeast Ohio native who received her MLS from Case Western Reserve University. She began her career as a reference librarian at the Cuyahoga County Public Library. She spent several years in San Diego managing a cooperative library system before returning to Ohio.
Rebecca Thompson, Growing Students and Science program coordinator, has been with the Education Department at Holden since 1999 and has worked in environmental education for many years. She coordinates the Growing Students and Science Program, a community partnership to build interest and ability in the sciences in public school systems, and leads Holden’s Junior Birders Club for children and teaches a number of children’s classes. She received her bachelor's degree in biology at Kent State University.
Charles Tubesing, chief horticulturist, is a graduate of Purdue University. Tubesing has been with Holden since 1986. He is responsible for the development of Holden’s plant collection, having extensive experience and interest in the selection of appropriate woody plants to fit specific landscape criteria and in plant propagation with a special interest in magnolias.
Michael Watson, conservation biologist, started at Holden as a conservation seasonal three years ago. He earned his bachelor's degree in biology from the College of Wooster and his master's in ecology and evolutionary biology from the University of Michigan. He spends most of his time on the deer browse project, a large-scale, long-term study attempting to measure the impact of deer on Holden's forests. He is also the coordinator for Holden's Bluebird Project, which relies on 50 volunteers to monitor and band bluebirds, tree swallows and other secondary cavity nesting birds that use more than 200 nest boxes on the Holden properties.
Marian Williams, manager of public programs, has been employed with Holden since 1987 and is responsible for Holden’s public programs and interpretation of the gardens and natural areas as well as a variety of other special projects. She received her undergraduate degree from Earlham College and her master’s degree from Purdue University.
Luke Williamson, is a two-year education intern at Holden. He recently graduated with an undergraduate degree in environmental education and interpretation from the University of Wisconsin-Stevens Point. He has spent summers working as an educator for Western Arctic National Parklands in Alaska and the Spring Mountains National Recreation Area in Nevada.
Greg Wright, nursery supervisor, is in charge of plant propagation at Holden. He earned his bachelors degree in horticulture at Brigham Young University and his master's degree in landscape architecture at Utah State University. Wright has been with Holden for eight years and teaches a variety of classes on horticulture and landscape architecture.
Non-Staff Instructors
Ian Adams is an environmental photographer, writer, and teacher specializing in natural, rural, historical and garden areas in Ohio. Since 1985, more than 6,000 of his color photographs have been published in books, posters, calendars, magazines and other publications. Ian has published 18 photography books and conducted more than 175 photography workshops and seminars. His books include The Holden Arboretum (University of Akron Press, 2000), Backroads of Ohio (Voyageur Press, 2006), Our First Family's Home: The Ohio Governor's Residence & Heritage Garden (Ohio University Press, 2008), Missouri Botanical Garden: Green For 150 Years (Missouri Botanical Garden Press, 2008) and A Photographer's Guide to Ohio (Ohio University Press, 2011) He lives in Cuyahoga Falls with his tabby cat, Fuji.
Pat Bilitar comes from a long line of eastern Kentucky coal miners and broke family tradition to become a geologist. After completing his undergraduate and graduate studies at the Ohio State University and UCLA, and Airborne and Ranger training at Fort Benning, Georgia, Biliter spent the next 30 years overseas working for the Army Corps of Engineers. Among other assignments, he served as the Deputy District Engineer of the Europe District in Wiesbaden, Germany, where he was responsible for military construction, humanitarian relief and host nation assistance in 90 European, African, Middle Eastern and southwest Asian countries. After retiring from federal service in 2001, he settled in Cleveland, Ohio, and within a year became a school guide at the Holden Arboretum. Inspired in high school by the writings of John Muir and Rachel Carson, Pat quickly realized that the Holden Arboretum was a perfect setting to share his lifelong love of natural history and conservation with coming generations of young Americans. Biliter is also an Ohio Certified Volunteer Naturalist.
Judy Churchill, AYT, RYT, CYT, an accredited yoga teacher of Satyanada Yoga and registered as an RYT at the 500-hour level with Yoga Alliance. In 2001, she received formal initiation in India from Swami Niranjanananda Saraswati and given the spiritual name, Jayasri. She later earned a level two accreditation from Satyananda Yoga Academy, Mangrove Mountain, NSW, Australia. Churchill maintains a web site with book reviews and articles on yoga at www.yogic-wisdom.com
Marilyn Dolence enjoys taking pictures of nature and scenics. She particularly likes shooting in BXW, infared and macro. Dolence has also experimented with x-ray photography. She was the featured artist for December concerts of City Music Cleveland and currently has a display of her work at the Crazy Lake Art House in Greenfield, Indiana.
Dan Donaldson is the district administrator of Lake County Soil and Water District. Having earned his bachelor's degree in environmental management from Cleveland State University, he assists local governments, landowners, and partner agencies with natural resource planning objectives, including special projects, ordinances, programs, conservation easements, program planning, administration and grant writing.
Denise Ellsworth, extension educator - horticulture, Ohio State University. Ellsworth earned her master of science at Ohio State University, School of Natural Resources and bachelor of science from Ohio State University's Department of Plant Pathology. Ellsworth coordinates commercial and consumer horticulture programming with a focus on plant identification, pest management, and environmentally-friendly gardening. Her nearly-200 Master Gardener volunteers teach, staff displays and care for demonstration gardens across the county. She also initiated Ohio's specialization programs for Master Gardeners, and has coordinated weed, insect and tree specializations. Along with Dan Herms, she coordinates the OSU Phenology Garden Network. She is also a garden writer for the Akron Beacon Journal. In her free time, Denise enjoys running, gardening and family activities with her husband and three children.
Bob Faber has been a consultant to conservation and environmental organizations throughout the region. He leads natural history programs across the United States.
Jacquelyn Gill, Gill is a PhD candidate in the Department of Geography at the University of Wisconsin at Madison. She has an master's ing geography from the University of Wisconsin and a bachelor's in human ecology from the College of the Atlantic. Gill’s research addresses how the extinction of North American megafauna (e.g. mastadons) during the last ice age influenced plant communities in eastern North America. She uses fossils of pollen, charcoal, and spores from lake sediments as proxies for environmental change and then reconstructs past vegetation communities. Her research has been published in the journal Science and the Proceedings of the National Academy of Sciences.
Andrew Hipp, PhD, a plant systematist and herbarium curator at the Morton Arboretum and has academic appointments at the University of Chicago and the Field Museum. He holds a doctorate from the University of Wisconsin at Madison. His research focuses primarily on the evolution and systematics of oaks and sedges, addressing the diversification of plant lineages using tools such as molecular phylogenetics, population genetics, cytogenetics and herbarium study.
Lisa Rainsong holds a Doctor of Musical Arts in Composition from CIM and is a member of CIM’s music theory faculty. She also has a Naturalist Certificate from the Cleveland Museum of Natural History and does field recording of bird songs and insect songs. She received a research grant from the Geauga Park District in 2009 to survey two of the Park District’s preserves for cricket and katydid species - survey work that is done largely by ear.
Billie Richards is a Signature Member of the following organizations: The Ohio Watercolor Society (also, a board member), The American Watercolor Society, The National Watercolor Society (currently showing a painting in California, with a prize), The Whiskey Painters of America. Her award winning paintings have been included in exhibitions throughout Ohio. Mrs. Richards has taught for many years at The Holden Arboretum.
Gary Meszaros, a retired Cleveland City School teacher. Meszaros’ photographs have appeared in many publications, including Smithsonian, National Wildlife, National Parks Magazine, National History, and Timeline as well as on numerous posters and calendars.
Randy Mitchell, PhD, a Professor of Biology at the University of Akron and is director of the Bath Nature Preserve. He holds a doctorate in biology from the University of California at Riverside. Mitchell’s research addresses evolutionary ecology of plant pollinator interactions, focusing on how plant mating patterns and success are affected by pollinator behavior and abundance.
Haans Petruschke is a leader for the Audubon Society's annual spring bird walks at Holden. He has a bachelor's degree from the American University.
James Runkle, PhD, a professor of biology at Wright State University. He holds a doctorate from Cornell University. Runkle’s research addresses the dynamics of plant communities and populations and the ecological characteristics of woody species in the eastern United States. Of particular interest are processes associated with tree death (creating holes or gaps in the forest canopy) and replacement in old-growth hardwood forests. Runkle has previously researched old-growth forests at The Holden Arboretum.
Gunter Schwegler is a fiber artist specializing in silk painting. His work in watercolor, acrylic and oil painting formed the basis of his style and technique. His recent work includes framed silk paintings, wearable art, banners, stage and set design, home furnishings, CD covers and public art space. His work is featured in Creative Silk Painting” by Jan Janis and Diane Tuckman.
Barbara Tercek, RYT, a certified yoga instructor and social worker is studying for her certification in yoga therapy.
