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Tour Guide: DAN MAHR

Dr. Dan Mahr has degrees in Biology and Zoology from San Diego State University and his doctorate is in Entomology from the University of California, Riverside. For over 30 years he was a professor of Entomology at the University of Wisconsin – Madison, where he specialized in pest management on horticultural crops. He has a strong interest in horticulture and was on the Board of Directors of the Cactus and Succulent Society of America for over 25 years and served as its president. He is an Honorary Fellow of that organization and was director of its Field Trips Program for 20 years, organizing and leading tours throughout the United States and Mexico, as well as Peru, Brazil, Chile, Argentina, the Canary Islands, Kenya, Namibia, South Africa, Botswana, Zimbabwe, and Madagascar. He has also traveled to England, Germany, France, Italy, Switzerland, Spain, Costa Rica, Australia, Fiji, New Zealand, Canada, and Zanzibar, as well as throughout the Caribbean. He and his wife Susan are originally from California and their hearts are still in the Southwest. For over 35 years they have been interested in the history, culture, and arts of the Pueblo peoples of Arizona and New Mexico and have an extensive collection of contemporary Pueblo pottery and other arts. Dan has visited the pueblos of Hopi, Laguna, Acoma, Zuni, San Ildefonso, Santa Clara, Picuris, and Jemez, as well as numerous archaeological sites of the Ancestral Pueblo Peoples.



Dr. Denny Schrock is a freelance garden writer and photographer with a Ph.D. in horticulture from the University of Minnesota and an MS degree from Colorado State University. During his university career he served as the state master gardener coordinator for Iowa, Illinois and Missouri. He was previously a garden editor with Meredith Corporation, where he edited 40 garden books under the Better Homes and Gardens, Scotts, Miracle-Gro, and Ortho brands. Schrock serves on the editorial advisory board of The American Gardener magazine, and in 2015 he was honored as a Fellow by GWA, the Association for Garden Communicators. Denny has extensive international experience, from living in Poland for two years, to leading student and master gardener study tours to Ecuador, South Africa, France, England, Belgium, the Netherlands, and Italy. In addition, he has traveled on his own to more than 30 countries around the world.



Eric Tschanz has been in the public garden world all of his career. He recently retired as the Executive Director of Powell Gardens where he spent the last 29 years. Through his involvement with the American Public Garden Association he has had the opportunity to travel and make connections with many U.S. botanical gardens. His personal travel and garden tours have taken him to England, Scotland, Ireland, Holland, France, Spain, Italy, Mexico, Costa Rica and New Zealand. Eric has an undergraduate in horticulture from Ohio State University and completed his graduate work at Longwood Gardens and the University of Delaware.




Kari Harper, owner of Hidden Treasures Tours, has undergraduate degrees in Communications and Art with an emphasis in Art History and a Masters in Project Management. Prior to Hidden Treasures Tours, Kari owned and operated a marketing and project management company. Kari began working with Mary Kroening in 2014 as her marketing consultant. She assisted in the overall tour planning and administrative operations of the company. Kari purchased the company in 2017. Kari’s travel experience has taken her internationally to the Bahamas, Canada, Costa Rica, Spain, France, Romania, the Netherlands, and Italy. Her passions include art, cuisine, history, and dance.



Mary Kroening, the founder of Hidden Treasures Tours, has over 15 years’ experience leading tours throughout the world. Mary has her BS from Concordia College and her MS from Colorado State University. She started her travel career by offering horticulture study tours to Costa Rica. She developed custom itineraries designed specifically for Master Gardener groups. Since that beginning she has arranged tours for gardeners, bird watchers, wine enthusiasts, natural history interest groups and others. Mary has two grown daughters and in her spare time enjoys travel, backpacking and gardening.




Pam Bennett is an Associate Professor with The Ohio State University and serves as the director of the State Master Gardener Volunteer Program as well as the Horticulture Educator and Co-Director for OSU Extension Clark County.  She has a bachelor’s degree in landscape horticulture and a master’s degree in Agriculture Education from The Ohio State University.  Her responsibilities include providing leadership for the Master Gardener Volunteer program of more than 3,500 volunteers and conducting consumer and commercial horticulture programs.

Pam specializes in herbaceous ornamental plant trials and evaluates more than 200 varieties of annuals and two genera of ornamental grasses; she presents programs on annuals and perennials as well as other landscape topics locally, statewide and nationally.  Pam has also lectured in Canada, China, and South Korea.  She is Chairman of the National Extension Master Gardener Committee, a Clark County Park District Commissioner, and is the Past-President of the Friends of the Ohio Governor’s Residence and Heritage Garden.  Pam is co-author of the award-winning book Garden-pedia, An A-to- Z Guide to Gardening Terms. She also writes a weekly gardening column for the Springfield News and Sun and the Dayton Daily News, authors the bi-monthly “Ask the Expert Column” for Ohio Gardener magazine. In addition, Pam is a frequent writer for popular gardening magazines and trade publications.


Tour Guide: SUSAN MAHR

Susan Mahr has degrees in Biology and Entomology and has been the state coordinator for the Master Gardener Program in Wisconsin for nearly two decades. As part of her responsibilities there, she has lead numerous educational tours to Costa Rica, New Zealand and South Africa. She has also hosted garden-related tours for HTT to Italy and New Zealand. In addition to leading tours, she has done extensive personal travel throughout the world, especially to see plants in habitat. Susan is also an avid gardener, with personal interests that include tropical plants, vegetable gardening, bulbs and perennials.