Over the past year the UC Davis Arboretum and Public Garden has managed to cut back water use across campus by over 30% from 2013—that is already well above Governor Brown’s recent 25% water reduction mandate. We are proud of this accomplishment, but we are not planning to stop there. We will continue to seek reductions throughout campus and the Arboretum. In this feature we will give you an insider’s look at how we’ve managed this decrease to date, changes you’ll notice in the near future, and how we are planning for a low-water future which will hopefully give you ideas for how you can do the same.
TARGETED TREE CARE
The benefits of trees are many: they help prevent carbon from being released into the atmosphere, they provide shade, fight erosion, and so much more, but when we reduce water to our lawns that can mean we inadvertently stress the trees living there too. To help alleviate this pressure and maintain tree health we have installed over two hundred slow-release watering bags on young trees throughout campus. Each one of these bags is filled manually from our campus water truck about once a week with approximately 10-15 gallons of water which then seeps slowly from small holes in the botton of the bag into the surrounding soil. This action not only targets young tree roots, it also reduces water run-off and evaporation. Each one of these bags saves about 1000 gallons of water a year per tree. LEARN MORE.
For mature trees, like in our oak grove (see photo top right on page 1), we apply water less frequently, but more deeply. During dry months, arborists recommend watering to a depth of three feet. To assist in this effort, the California Center for Urban Horticulture at UC Davis has developed instructions for how to purchase, assemble and deploy a unique watering device called the tree ring irrigation contraption (TRIC). For more information on gathering the materials necessary to create this device and the process for assembling it, visit http://bit.ly/tric-your-tree.
While most of our main campus landscape irrigation is part of a high-efficiency computerized system, there are still some areas, mostly in the central part of the Arboretum, that require hand watering during the day with hoses and/or spray irrigation. Not only is this method labor intensive—it requires staff who can start, stop, and move it—it’s also inefficient because it often results in overspray and wet guests!
We do have plans to install new irrigation systems in these areas as funding becomes available, however, since installing systems from scratch is very expensive, it will need to be phased in over many years. In the meantime, the university is investing in more efficient, but temporary irrigation systems. These temporary systems will be set up this summer and allow for automated, more precise nighttime watering. As permanent systems are funded and installed, the temporary systems will be removed.
Thanks to the high-efficiency, computerized system that controls watering on most of campus, we can easily target turf for irrigation reductions. Some lawns will even be allowed to go dormant through the summer. However, lawns with high-event use uses like the Quad and fields used for athletics or student recreation will continue to be maintained.
We have also identified lawns for full-scale landscape conversions. Look for this change on the median near the Mondavi Center for Performing Arts. While the trees in the lawn will be maintained, the turf will be replaced with Arboretum All-Stars, California natives, and other regionally-appropriate plants.
When given the option, planting in fall is always our first choice; temperatures are dropping, but the soil is still warm. Those are ideal conditions for root development, plus, with any luck from Mother Nature, seasonal rains should be right around the corner. Plan your new drought-tolerant garden over the summer and visit our plant sales in the fall for a great selection of regionally-appropriate, low-water plants such as Arboretum All-Stars and California natives.
Thank you to “The Best Colleges” website for recognizing the UC Davis Arboretum and Public Garden in their “50 Most Amazing University Botanical Gardens and Arboretums in the U.S.” LEARN MORE.
The article sites that the organizations listed not only beautify their campuses and communities, but also serve as environmental stewards, outdoor classrooms, and living laboratories.
Here is a little bit about what they had to say about the UC Davis Arboretum and Public Garden:
The seventeen gardens that make up UC Davis Arboretum are a beautiful testament to nature’s instruction. Students not only use the 100 acres of sprawling landscape for “peaceful contemplation,” but they can also use the gardens as hands-on learning facilitators in dozens of classes offered by the university. This free resource enables students to get their hands dirty while observing a living textbook or conducting meaningful ecological research. A variety of internships are offered in conjunction with the gardens as well in topics such as sustainable gardening, plant propagation and nursery operations, and Geographical Information Systems (GIS). The arboretum recently received a 4-out-of-4 star accreditation by the Professional Grounds Management Society for outstanding performance in the areas of environmental stewardship, economic performance, and social responsibility.
We appreciate the recognition of our gardens as well as the students and programs that support them.
The Aggie Public Arts Committee, funded in part by ASUCD, commissioned a mural on the sidewalk near the Nelson Gallery, along Arboretum Dive. Conceptually, the mural is based on reimagined landscapes and wildlife, using 3-D illusions of space with an element of fantasy. Next time you are in the Arboretum, we hope you’ll stop by to see it!
Thank you Kari Kiyono for creating such a beautiful mural for us to enjoy.