Tree Walk: Urban forest and edible gardens at the SF Flower & Garden Show

Two BART trains and three buses. This was the route generated by 511.org to get me from Ashby to the Cow Palace, site of this year’s San Francisco Flower & Garden Show. Luck was with me. I took a direct BART to the city, met a friend for a long lunch, then took another direct BART to Balboa Park. At the Balboa station there was a shuttle waiting to transport visitors to the show!

I bought my half-day ticket in advance rather than at the door so I would definitely attend the show. I wanted to see the urban forest garden - “Healthy Communities Grow on Trees” - developed by the USDA Forest Service, California Urban Forests Council, and the Mandeville Garden Company, but I would not have a companion so feared that I would back out at the last minute. In addition to the urban forest garden, I also wanted to see the garden that was the subject of a San Francisco Chronicle series on the show: “Ripples and Rays” by East Bay designers Joy Lung and Christian Ehrhorn of Misty Morning Gardens. (Joy Lung is the sister of a friend).

I saw both gardens and discovered a third: “It Doesn’t Take a Hectare” by Sommersett Designs and Leiber Landscape Services, both of Walnut Creek, pictured above. (Note the hare sculpture by Phillip Glashoff and the play with the word “hectare.") The designers used the same plant palette in four different designs (pictured below). Plants included herbs, lettuces, Meyer lemons, and vegetables like radishes and celery. The marketing material, written by Shelley Somersett, APLD, of Somersett Designs, describes the concept as follows:

It doesn’t take a hectare to feed a family four square Heirlooms in the Cottage or on an Urban Roof Wine Country Tuscan or Berkeley “Locavore’ No GMOs are in our food, the nutrients are proof.

Take some dirt, add sunshine, clean water and fresh air, A designer for the garden and you’re half way there. When Edibles are planted, sustainable’s the fare.

Breakfast, lunch and dinner your neighbor too can share The earth still laughs in flowers, the chef’s gourment affair Feed a hungry neighbor, teach the world to share.

The primary draw for me was the urban forest garden. I have worked as both a community and an urban forester. (There is debate about the definition and scope of the term “urban forest” and thus urban forester; it is more accurate to say I was a street tree manager.) I am very interested in the ecosystem values of designed landscapes and wanted to see the interpretation offered by a major forestry agency like the U.S. Forest Service.

While I was familiar with information provided in the urban forest garden, it was the most uniquely themed garden at the show. The garden was aesthetically pleasing; this is very important to counter lingering misperceptions that ecosystem gardens or landscapes are unattractive. Also, the exhibition was well designed and educative. Numbered signs within the garden highlighted “sound urban forestry concepts.” For example, sign #7 encourages the removal of lawns and replacement with “grass-like species” like dwarf sedge, pictured below. The bench in the photograph was designed by West Coast Arborists using street trees.

Other urban forestry best practices include native plant choices to provide food and habitat for insects, birds, and other animals (sign #4 pictured above, right) and planting larger stature trees to generate environmental benefits like carbon and particulate matter sequestration and storm-water attenuation.

A large stature trees like a coast live oak (Quercus agrifolia) saves 6,010 kilo Watt hours and intercepts 6300 lbs of carbon and 26,900 gallons of stormwater over its lifetime. This compares to 3,270 kWh, 5400 lbs of carbon, 18 lbs of air pollutants, and 14,800 gallons of stormwater for a medium, ornamental tree like an evergreen pear (Pyrus kawakamii). Source: exhibit marketing material.

At the exit I was handed a flyer alerting me to California State Senate Bill SB1527 which proposes to sell the Cow Palace and convert the land to condos and a strip mall. For more information and a petition visit the Save our Cow Palace website.