Board of Directors

Mike Rippey, President

President of the Board from 2011 through 2015 and reappointed in 2019.  Finance Committee Chair.

Mike has helped the Garden professionalize its business activities. Mike has built three companies during his career which had 300, 500 and 1100 employees; two of the companies went national doing business in all 50 states, and the third was a Bay Area coffee chain of 30 drive thru locations (Caffino).  Mike also has extensive real estate experience, having developed housing subdivisions of 55 and 115 units, owning over 100 apartment units, and speculated in various land ventures. Mike graduated from Notre Dame with a degree in International Relations in 1970.


Gretchen Bartzen

Director, Governance, Garden, and Fundraising Committees.

In 2012 Gretchen retired as Director of Development and Parent Relations at The Seven Hills School where she served for 17 years, and assumed the executive director position at the Garden as a volunteer. Prior to that she had served as a board member and fundraiser for six years at the Garden. At Seven Hills she directed two successful $5 million dollar capital campaigns for building projects. Prior to her development work, she was a secondary education teacher of English and related subjects for 20 years. She now primarily raises major gifts for capital projects at the Garden.

Susan Hewett Chapman

Susan is a long time resident of Danville, and very involved in the civic and cultural life of Danville, Walnut Creek, and the East Bay communities. She has been an active member of AAUW, and served 9 years as a trustee at Seven Hills School in Walnut Creek. She was chair of the Governance Committee there, and also helped with the Development Committee. She was also active with The Athenian School parent board. Susan is a graduate of Scripps College and the University of Minnesota. She is a former elementary school teacher and worked in business administration and human resources prior to raising her family. Susan has volunteered extensively in education and civic organizations since moving to the East Bay in the 1980s. She was elected to the Garden Board 2015.

Nina Bancroft Dickerson

Bancroft Family Board representative, Governance Committee.

Nina is Ruth Bancroft’s daughter. She is a retired social services professional and active community leader. Nina has been an active volunteer and Bancroft family advisor to the Board and contributing member at the Garden for over 20 years.

Spencer Dress

Governance Committee, Strategic Planning Committee, Garden Gala Committee.

Spencer grew up Yuba City and moved to Walnut Creek in 2012 where he attended Diablo Valley College and graduated from Saint Mary’s College of California with a degree in Political Science. He now works with his father operating and managing personal storage facilities in Northern California. He is passionate about getting younger people involved in civic-minded activities and wants to help foster the next generation of leaders to ensure that our community remains one that we can all be proud to call home.

Tracy Fletcher


Tracy F.

Executive Director

Tracy Fletcher grew up in Kansas City and joined Verizon Wireless at a very early age. She worked through the ranks moving from state to state with the company including Iowa, Georgia and finally ending up in California. After almost 30 years of service she felt it was time to leave the corporate world behind and pursue her true passions: animals and gardening. Tracy is an avid animal activist and has volunteered for various rescue groups and shelters. Her business experience and love for gardening makes her a great fit for The Ruth Bancroft Garden. She started out as Office Manager, then Event Manager, Sales Director, COO and now Executive Director. She loves that each day is a new adventure and allows her to meet so many great people. One of her dogs is frequently by her side when working at the garden which allows her to combine her two favorite things.

Gail Giffen

Finance Committee, Sculpture Show Committee, RBG Legacy Society member.

Gail is a real estate investor and past owner of two Bay Area pizza restaurants.  Gail is an art collector and has served on the annual Sculpture Show Committee since 2006 and a board member on and off since then. Gail is also active in supporting all of the Garden’s annual major fundraising events.

Cheryl Nobusada

Finance Committee, Donor Recognition Welcome Wall Project Manager.

Cheryl has more than 20 years of operational, compliance and financial/risk management experience.  Most recently, she was the VP of Investor Operations at LendingClub. Previously, Cheryl was the Director of Client Services at a San Francisco based technology hedge fund and has had various roles at Deutsche Bank working with individuals to achieve their financial goals.  Cheryl now enjoys consulting for small businesses by helping them become operationally efficient.  She also thrives on volunteering with local non-profit organizations to support her community.  She currently serves on the Hope Walk Committee for Cancer Support Community and is also a volunteer at Lamorinda Villages and White Pony Express. Cheryl and her husband, Ryan Kosakura, have been members of the Garden since 2015 and she has volunteered in the Nursery and various Garden events since that time.

Rich Perona

Garden Committee Chair, Folly Complex Renovation Co-Chair.

Rich received a bachelor of BS in ornamental horticulture from Cal Poly San Luis Obispo. He served in the Army for two years after graduating, one year at Fort Story Virginia Beach, and one year in Korea as a company commander at a missile base. After the Army, Rich worked for Environmental Care Landscape as an account manager for 41 years and then became facilities manager at Rossmoor for many years. He managed the Rossmoor staff of 20 gardeners and supervised the independent contractors who performed maintenance around all the homes of Rossmoor, and the tree company that had two full-time crews working in the valley. Rich, now retired, has been a volunteer in the Garden weeding and helping the Garden and Office staff with events and numerous other Garden projects for the last 5 years.

Bernie Rose

Treasurer. Finance Committee, RBG Legacy Society Member.

Bernie has a BA and a PhD in chemistry as well as a law degree from John F. Kennedy Law School. Like his wife Julie, his first career was as a scientist. He worked for Eastman Kodak, Polaroid, 3M and then Chevron for many years. After he obtained his law degree in 1985, Bernie practiced with several law firms over the years, first in personal injury law, then environmental and contract law, and most recently intellectual property (primarily patent) law with the firm of Squire, Sanders and Dempsey. He retired from Squire, Sanders in 2013, but still practices as an independent patent agent for a few clients.  Bernie has served on the San Ramon Environmental Counsel, and has been involved as a volunteer at the Garden with his with wife Julie since 2010.

Julie Rose

Secretary. Finance and Governance Committees, RBG Legacy Society Member.

A member of the Board since 2019, Julie is retired from careers as a research chemist with 3M and Chevron Research Company, and a lawyer with the Law Firm of Randick, O’dea and Tooliatos, in the areas of Environmental law, Contract law, and Real Estate. Julie Graduated from Lawrence University, Appleton, Wisconsin in 1975 with a degree in chemistry. Julie became interested in cacti and succulents after her first visit to RBG in 1992 and has been growing them ever since. She is past president of California Cactus and Succulent Society (Oakland club) and has been an active volunteer at the Garden and Nursery and major events since 2010.

Earl C. Ruby III

Vice-President. Finance Committee, Garden of d’Lights Committee Chair.

Earl owned and ran a software consulting company in Walnut Creek for 9 years. He is currently a Staff Engineer at VMware, orchestrating cloud infrastructure and Kubernetes clusters for GPU-based ML/AI projects. He has led an engineering teams at Apcera, built cloud storage reference architectures for Seagate, created web-based settlement, network quality of service and fraud-detection software for the wholesale telecom industry, and built wireless telemetry networks for Schlumberger. He earned a bachelor’s degree in Computer Science from Cal Poly, San Luis Obispo, with a concentration in Artificial Intelligence. He has been an extremely active volunteer for the last four years.

Susan Ruby

Garden of d’Lights Committee, Garden Gala Committee, and Folly Complex Renovation.  

Susan holds a bachelor’s degree in Dietetics from Cal Poly, San Luis Obispo, and worked as a Nutritional Specialist for two years before she earned a Certificate in Engineering Drafting from Diablo Valley College, and worked as a commercial architectural drafter for 15 years.  In 2010 Susan completed a Master’s in Business at John F. Kennedy University and in 2011 she also became a certified personal trainer.  Susan has volunteered at Ruth Bancroft Garden for eight years.  She has worked in the office, the Kiosk, and at special events. She has taken the Docent Program to learn more about the plants in the Garden and considers RBG one of her hobbies.

Christina Sammartino-Ascencio

Garden Gala Chair, Docent

Growing up in Alaska, Christina Ascencio has had an appreciation for nature her entire life. She now enjoys honing her green thumb in the East Bay, where she has lived for more than 10 years. For 17 years, Christina has worked as a fraud specialist for Wells Fargo Bank, an organization that supports volunteerism and encourages its employees to join local nonprofit boards. Christina knew she wanted to get more involved with the Garden after visiting for the first time in 2016 for a plant sale. Shortly thereafter, she completed RBG’s docent program to further her knowledge of drought-tolerant plants and has since volunteered at the Garden in a variety of roles. Christina has also proudly served as chair for the annual Garden Gala since 2017.

Marco Vaticano

Membership, Member Coffee Project.

Marco is a real estate agent with Compass in Danville, and founder of the Vaticano Group through Compass, with his sister Juliana. He graduated from San Diego State University, where he was the Programs Director of the Real Estate Society, organizing 10 events, as well as a University Outreach Member of the NAIOP, the leading commercial real estate networking platform in North America. Marco is an avid gardener and supporter of the gardening community, he now helps promote RBG through his clientele, word of mouth, and social media. He became an active volunteer when he helped welcome the public at Ruth Bancroft’s Celebration of Life at the Garden in 2018, and enjoys every opportunity to assist with events throughout the year.

Mary Walker

Fundraising Committee, Water Conservation Task Committee.

Mary worked in telecommunications for MCI for over 15 years. In 1999 she and her husband purchased Daily Graphics, a print service bureau, and reorganized the company in 2004, and launched an all-digital print company,Daily Digital Imaging (DDI), specializing in marketing through the use of variable data printing (VDP).  Their digital press does not use water, chemicals or solvents in the print process and reduces paper waste with the ability to provide a single press proof. DDI qualified as a Bay Area Certified Green business in 2005 and advocates the importance and advantages of using digital to print.  DDI won the Pleasant Hill Green Business award in 2014. Mary is a founding member of the Pleasant Hill Green Committee, established in 2005, whose mission is to advocate “green” business practices in the community. Mary serves on the boards of the San Francisco Professional Food Society and Mt. Diablo Business Women.

Monique Young

Garden Committee, Fundraising Committee, Garden Conservancy Representative, and Horticulture Advisory Committee.

Monique who is now associated with Compass Real Estate, is a residential real estate broker in Walnut Creek, working here since 1987.  In service to the real estate community, she has been past chair and a member of the Contra Costa Association of Realtors’ Professional Standards Committee since 2000.  Professional Standards is responsible for hearing ethical complaints against Realtors from the public or other members; it also arbitrates financial disputes amongst members.  Monique has taught real estate classes at Diablo Valley College since 2000.