PLANTS; COMMUNITY, FOOD AND ECOLOGY

23 January 2009
Urban Harvest
Houston, Texas

Community and Food - Mark Bowen

Mark Bowen, the Urban Harvest (UH) executive director, promoter of the Houston Christmas tree recycling program, and author of Habitat Gardening for Houston and Southeast Texas, Naturalistic Landscapes for the Gulf Coast, and the Houston Chronicle gardening column, spoke next. 

He said that he sees UH as a catalyst, helping to start and maintain gardening throughout Houston.  Its chief focus is on more than 100 community gardens and orchards in the area.  Some of the gardens have special missions:  helping HIV-positive individuals, domestic abuse victims, or VA brain trauma patients.  They also support gardens at 19 schools in the Houston region, most of them Title 1, lower-income schools, with the gardens integrated into the educational curriculum.  UH also supports adult education with programs on rainwater catchment, seed saving, and organic methods.  Plus, they are involved in managing the Houston farmer’s market, recognizing that local food is best (typically, food travels 1500 miles from the grower to the eater, and consumes 12-15 calories of energy for 1 calorie of food).

To better explain UH’s work, he explained the experience of the Alabama gardens, Braes Interfaith farm, and the Garden Oaks garden.  The Alabama garden was founded in 1985, and now has 50 raised beds, rented out for $5/month (with a waiting list!).  It is a place for nutrition education, senior appreciation, and mentoring of younger people in the inner city neighborhood.  The Braes Interfaith farm is in a utility easement in southwest Houston, supplying a food pantry next door with 12,000 pounds of food each year, and training gardeners in an apprenticeship program.  The Garden Oaks garden is within a Title 1, Montessori school, where it seeks to teach children outdoors.  Its program uses the garden to teach science, math and language arts in a discovery-based approach.  It has succeeded in raising standardized scores, and lowering discipline problems and dropout rates.

UH has a full-time curriculum aide, Michael Bogoy, who has extensive outdoor classroom experience, and is involved in outreach to 21 schools, 27 teachers, 15 part-time school instructors, and 1709 students.  He has found that gardens allow children to forge an early link with the soil and nature, to celebrate the seasons and migrations, to understand water recycling, to see the importance of pollination by bats, birds, and insects, and to exercise their creativity in inventing new dishes (persimmon popsicles!).

Through Terry Reed’s work, UH is also promoting gardening and farming as a career, connecting local workers with local jobs on local farms.  One way to introduce new and young farmers to the business is through the “Gardener’s Corner”, a part of the Houston Farmer’s Market where space can be rented for $2 per $30 sold. 

Mr. Bowen sees great encouragement in kids’ vision for the future, and how it incorporates gardens and nature.  He showed a drawing that a child did of the Benavidez Elementary School, located in the poor and high-density Gulfton neighborhood, yet hosting a vital garden full of produce and people.

Questions and Answers - Mark Bowen

Q: How many people attend the Farmer’s Market?  Mr. Bowen said that 1500-3000 attended a Saturday Market, visiting three double rows of stands.

Q: Are soils tested at garden sites?  Mr. Bowen said that the soil is tested for lead and hydrocarbons if the site is near a highway, road, body shop or dry cleaning establishment.  But, he added that it is generally not a major concern, since the gardens use raised beds, and do not involve tilling the underlying soil. 

Q: Does Urban Harvest hold special Earth Day events?  Mr. Bowen said that yes, they did have a “Spring Fling” event at Discovery Green downtown, and had sold over 6000 fruit trees on one Saturday.

Plants and Ecology - Damon Waitt

Damon Waitt spoke afterward.  He is a senior botanist at the Lady Bird Johnson National Wildflower Center, the author of Texas Wildflowers, the originator of the “Pulling Together” initiative for controlling invasive plants, and board president of the Texas Invasive Plant and Pest Council.

Dr. Waitt started with a brief history of the LBJ National Wildflower Center, explaining that it was founded by Lady Bird Johnson and Helen Hayes in 1982.  It moved to its current Hill Country location southwest of Austin in 1997, and was absorbed by the University of Texas in 2006.  In addition to its traditional interest in native landscapes and environmental education (they endorse the idea of No Child Left Inside!), the Center is part of the Kew Gardens Millennium Seed Bank, the National Plant Network for native plant information, and a cooperator in developing LEED standards for sustainable landscape.

In connection with the Center’s interest in native landscapes, botanists there have long been concerned about the invasion of exotic plants (or as Lady Bird termed them, “plants with no socially redeeming value”), and recently started the “Pulling Together Initiative” to monitor and control these exotics.  They recognize that exotics can be seen differently by the horticulture industry, which may consider an invasive plant a robust and profitable product.  Nevertheless, the threat to native ecosystems is serious.  E.O. Wilson said that the two great destroyers of biodiversity are, first, habitat destruction, and second, invasion by exotic species.  Recent studies have found that 50% of rare and endangered species are in fact at risk due to invasives.  While importation of exotic plants has been a long tradition, their introduction has accelerated with the rise in global trade and Internet sales.

Texas examples of exotic invasives include Cogongrass, Giant Salvinia, Giant Cane, Tamarisk, Chinese privet, Old World Bluestem, Water Hyacinth, Kudzu, Alligator Weed, and Chinese Tallow, Chinese Wisteria, and Buffelgrass.  The problems with these plants vary.  For example, Cogongrass burns at a different frequency than forest trees, making it difficult for the two to coexist.  Giant Salvinia shades out native competitors in such places as Caddo Lake, and when the Salvinia dies back seasonally, its vegetation rots and lowers the dissolved oxygen to a level that kills fish.  Giant cane is a concern because it is aggressively invasive, and the biofuel industry has unfortunately chosen it as a biomass source.  Tamarisk, or Salt Cedar, lines many western streams such as the Rio Grande and Pecos, and is literally sucking these river dry.  Chinese Privet, or Ligustrum, is an example of how a plant’s spread can be delayed, and then be exponential (it was introduced to the U.S. in the 1890s, but its rapid expansion did not start until the 1960s).  Throughout the Texas coastal prairie, Old World Bluestem, particularly KR Bluestem, is supplanting many native grasses that provide superior forage.  Water Hyacinth covers many southern bodies of water, and in fact, coats the entirety of the lower Rio Grande, blocking it from reaching the Gulf.  Kudzu, the poster child of invasive plants, was brought to the U.S. as forage and erosion control by the USDA in the 1940s, but soon became known as the “plant that ate the South”.

In all, the Texas Department of Agriculture lists 33 species on its noxious plant list.  However, botanists had originally submitted a list of 200, most of which were deleted by horticulture representatives who were concerned about losing profitable plants.  The Texas nursery industry has also lobbied successfully for the Texas list to take precedence over any local ordinances that might be more restrictive. 

Concerned about this political trend, and the lack of information about Texas exotics, statewide invasive species conferences were convened in 2005 and 2007.  As result of these conferences, a website to disseminate information about the threat and control of invasives was mounted at www.texasinvasives.org.  The Wildflower Center’s main website, www.wildflower.org, has also provided an “Ask Mr. Smarty Plants” section, which has had 2.6 million users, 21.3 million page views, and fielded 165,000 questions in the year 2008 alone.  The Center also launched the Invaders of Texas Citizen Science effort to collect GPS information and photographs of various exotics throughout the state, presenting the information through Google Maps.  Also, a state non-profit, the Texas Invasive Plant and Pest Council, was organized in the fall of 2008 to spearhead exotic plant monitoring and control.

Dr. Waitt stressed that there are other groups that are active in the area as well.  The National Park Service estimates that 2.6 million acres of parkland are contaminated with exotics, and to try to stem this tide, the Service has posted a website, www.beplantwise.org.  The website urges users to know their plants, use non-invasives, watch out for hitchhiker plants, use weed-free soil, mulch, and seed, remove berries from invasive plants, and dispose of invasive plants carefully (think of all the Chinaberry wreathes that may go to the landfill full of berries).  The Garden Club of America has launched a program called Plantwise Plant Awareness to help gardeners come up to speed.  New state Invasive Plant Councils, like those in Texas, California, and most states east of the Mississippi, have sprouted since 2007 in Oklahoma, Washington, Oregon and Louisiana.  The Brooklyn Botanical Garden has offered native options for 148 invasive plant species found in the U.S.

Nevertheless, there is still more outreach and persuasion to be done.  Wal Mart, Home Depot, and Loew’s continue to sell invasive exotic plants, and there is concern that they will create a homogenized landscape, lacking the regional identity that Lady Bird Johnson valued so.

Comments, Questions and Answers - Damon Waitt

Q: Has there been any successful contact with developers?  Dr. Waitt said, yes, that the developers of the old Muehler airport in Austin had been receptive, but many other developers still lean toward “Trash Ash” and Bradford Pears because they establish easily and quickly.

Q: What is the connection between LEED standards and native plant use?  Dr. Waitt confirmed that use of native plants would be a core part of LEED landscaping standards.

Comment:  Exotics have an attraction for two reasons.  For sellers, hybrids and cultivars can be copywritten or patented, securing future profits, while natives cannot.  As buyers, the gardening public can tire of natives, and seek out new plants to use, even if they carry invasive risks.

Comment:  Dr. Waitt said that there is some encouraging news on efforts to control exotics.  Mark Simmons has been researching this at the Center, in a project called “Bullying the Bullies”.  He’s found that overseeding Bastard Cabbage with dense plantings of wildflowers can allow the native forbs to outcompete.  Also, he’s discovered that hot summer prescribed burns can reduce KR Bluestem from 60-80% dominance to a 5-10% presence.

Comment:  Dr. Waitt sees encouragement too from the Invaders of Texas citizen science program.  Started in 2006, the program has conducted 24 workshops and established 21 satellite groups (in Midland, Dallas, Fort Worth, Lubbock, Austin, San Antonio, Houston, Brownsville and elsewhere).  358 volunteers have made over 5300 observations, finding 140 nonnative species.  After identification, control efforts begin. The Center hopes to expand this model nationwide.  Some critics have questioned the validity of lay data, but exotics tend to be common and easily identified, so Dr. Waitt thinks that the information should be pretty robust.

Comment:  Judy Boyce reported that the Harris County Flood Control Task Force had sought to discourage the Flood Control department’s use of Bermudagrass, but the agency had claimed that there were no reasonably-priced, available natives.  Dr. Waitt said that was the experience with the highway department and state forest service too, but that there were promising possibilities of a turf grass made of a mix of five native species.

Q: Is it possible to sterilize exotics to limit their spread?  Dr. Waitt said that non-bearing varieties of nandina had been developed, but generally it is difficult to propagate plants if they are sterile.

Comment: Dr. Waitt was encouraged to work more with the land grant schools, and urge them to focus more on natives.