Native Plant Rescue
Last week, at the Arizona Conservation Information Sharing Meeting hosted by Tucson Water, we were given a tour of the Pima County Native Plant Nursery by Jessie Byrd, the Nursery Manager. The idea behind the nursery is deceptively simple - remove native vegetation from a landscape before development occurs, relocate them to the nursery where they can grow in conditions that simulate the local environment, and then use them on public works projects such as parks, roadway medians, or stormwater detention basins. The nursery cannot sell plants to the public - they are not allowed to compete with commercial nurseries - but local government gains access to drought-tolerant, native plants at the cost necessary to fund operations at the nursery.
Put in practice, the nursery is able to lower construction and operations costs by a significant margin. According to the U.S. Environmental Protection Agency's WaterSense program, outdoor landscaping can require between 15-30% of total water consumption for institutional buildings (e.g., hospitals, office buildings, or educational facilities). Based upon an evaluation of evapotranspiration rates for typical vegetation, we estimated that native / drought-tolerant landscape design can reduce landscape irrigation by nearly 80% over conventional design. In addition, the use of native landscape can eliminate the installation of automated irrigation systems, lowering up-front irrigation costs. At commercial landscape prices, we estimated a 7-year simple payback for the drought-tolerant design - yet the Pima County Nursery is able to shorten that payback with lower prices, and public institutions are playing the "long game."
The work at the nursery is both challenging and innovative. Baby saguaro cacti end up at the nursery in clumps, and volunteers need to pry the cacti apart from one another into individual pots. Certain plants are put in 4" diameter, 4'-long PVC pipe to promote 3'-long root systems that will survive the Arizona landscape once planted in roadway medians. The staff clearly love their job.
Kudos and thanks to Jennifer Davidson of the City of Scottsdale and Candice Rupprecht of Tucson Water for organizing and hosting a great learning event.