While the Water Action Team has collaborated with the Marys Peak Group of the Sierra Club and other local organizations on six schoolyard native arboretums, we will focus this page on the first collaborative schoolyard native arboretum.
Crescent Valley Native Arboretum Project
Goal
The native arboretum creates an outdoor research laboratory for high school students to study and appreciate Willamette Valley native trees, shrubs and herbaceous plants. Students can also study the interaction of the arboretum with Jackson Creek and the local environment. The arboretum improves the health and functionality of Jackson Creek and the local ecological system. Watch the narrated slide show below for an overview of the Crescent Valley Native Arboretum.
Background
The arboretum, sited on a former turf field to the west of Crescent Valley High School and adjacent to Jackson Creek, is now shaded with native trees, shrubs and perennials. Wood chip walking paths, trail signs, interpretive displays, benches and a welcome sign invite visitors.
Site Background
There are no records or clear indications how the site was used during Kalapuya settlement over many thousands of years. There is little question, however, that this site was in a water-logged valley teeming with beaver, cutthroat trout, Pacific lamprey and hundreds of other species existing in prolific numbers. Following the slaughter of the beaver in the early 1800s, an 1850s-era vegetative survey recorded the site was an Ash marshland. The site was part of a riparian wetland of a tributary draining down to Jackson Creek from what is now Chip Ross Park.
An OSU Oral History archived at the Valley Library indicates that the site was farmed in 1906, but that there were still vestiges of native flowers in the agricultural field.
Crescent Valley High School Campus was built and opened in 1971. The site was elevated out of the floodplain and wetland with construction-grade (poor soil health) fill material. The Arboretum site was then covered with turf grass, mowed and left mostly unused for decades.
Two site uses between 1971 and 2010 include:
- The northwest side was a vegetable garden with fruit trees, initiated and maintained by a faculty member from the 1990s and first few years of the 2000s. The garden was abandoned in the early 2000s and deteriorated to weeds and turf.
- The southeast portion of the site was originally a beach sand volleyball court, but it also fell into disuse and was covered with turf grass in the late 1990s. The beach sand was still in place and in pristine condition, just inches below the turf grass when the Arboretum was initiated in 2010. When we dug up the pure beach sand and wondered why it was there, one long-time employee remembered the volleyball court and could explain this strange phenomenon.
Project Initiation
The native arboretum project was initiated by the Marys Peak Group (MPG) of the Sierra Club, with support from the Corvallis Oddfellows Fraternal Order and other local groups. The MPG offered their services to the Corvallis School District to create and install native arboretums at each of the school campuses. The school district agreed to collaborate. Crescent Valley High School was chosen as the initial site due to its abundance of unused open space adjacent to a creek. The preparation and approval process were initiated and planned in 2009. Implementation began in 2010. See video above for construction and planting details. Many organizations provided funding to kickstart the project. By 2015, the Corvallis Sustainability Coalition Water Action Team stepped forward to take the maintenance lead in collaboration with the MPG and the High School Student Environmental Action (SEA) Team.
Soil Regeneration
In 2010, Republic Services trucked in tons of rich compost, Stalford Farms donated about 100 bales of straw, wood chips were delivered by Limbwalkers and Buena Vista Tree Company, and Grocery Outlet donated bales of cardboard. All of this organic matter was layered into a form of sheet mulching to ultimately create a rich soil mix on top of the existing degraded soil. The intent was that the nutrients from the sheet mulching would leach during rains into the deeper soil and provide the appropriate soil environment for the intended young woodland. Tim Brewer Arborists donated and placed the logs outlining the arboretum. Tim Brewer Arborists donated and placed the logs outlining the arboretum. The system worked and we now have a nutrient-rich, regenerated living soil that is supporting a healthy arboretum.
Native Species
A diverse variety of mid-Willamette Valley native trees, shrubs and perennials were purchased from Sevenoaks Native Nursery with private funding and planted in November 2010 by High School students, teachers and volunteers from the MPG and Oddfellows. Professor Ed Jensen and David Zahler of OSU School of Forestry provided gratis consulting on tree species and planting considerations. Trees included: Oregon white oak, bigleaf maple, vine maple, Pacific madrone, white alder, red alder, cascara, Oregon ash, American hawthorn, and Willamette Valley ponderosa pine. Shrubs included osoberry, mock orange, California hazel, coyote bush, viburnum, ocean spray, blue elderberry, salal, ninebark, western spiraea, snowberry, Oregon grape, red-osier dogwood and red-flowering currant. Perennials and ferns included milkweed, fringecup, red columbine and sword fern. Following the initial planting in 2010, students have planted additional native species with our financial and mentoring support each year to fill in the rapidly growing arboretum.
Interpretive displays
Displays are located throughout the arboretum. A welcome sign, designed by Brad Johnson in the Crescent Valley High School colors and font, greets visitors on the south side of the arboretum facing the student parking lot. Other displays by Element Graphics illustrate ecosystem functions of riparian and oak woodlands in the Willamette Valley, the values of native plants, and how these natural functions and systems have been lost in Benton County since the 1850s. Additional interpretive displays accompany each plant species. Students in various classes study the growth rates, carbon sequestration, general condition, behavior, and fauna habitat value of each plant. They also analyze the evolution of the soil and interpret the impact of the growing woodlands on the surrounding environment. Humanities classes use the woodlands for pertinent studies and creative exercises. Most importantly, students and teachers develop a greater appreciation of our local environment and the impact it has upon their lives. The arboretum is a special place to be on campus.
Current Arboretum Conditions
The trees and shrubs are now in early adolescent phases. The trees range from 15 to 25 feet in height, and the shrubs range from 3 to 15 feet in height. Trees now shade significant portions of the arboretum, and the early succession weeds and grasses are no longer the biggest bullies on the site. The native plants are taking back their land. The soils are fertile and hold moisture. Even during the severe droughts of the past two years, no watering was required for the plants. The shaded paths and benches are now refreshing retreats on the campus. The next ten years of growth should bring the plants to a maturity level that will turn the arboretum into a fully shaded woodland.
The years of annual replenishing of wood chip trails are paying off with a soft matting for walking.
The one area that needs constant attention is the cultural relevancy of the arboretum in the school environment. The high turnover of students, faculty and administration requires the team to keep the arboretum relevant to the high-paced and structured school practices. Inspiring the faculty to understand the value of the arboretum for educational purposes takes a renewed series of actions with every new school year. The continued existence of the school SEA Club is the one constant that provides a solid link between the arboretum and the school culture.
2022 Work Plan
- Prune the rapidly growing trees and shrubs to stimulate upward growth, minimize interspecies competition and allow easy and comfortable human access along all of the paths
- Prohibit invasion of thistle, Armenian blackberry, dock and other invasive, exotic plant species
- Replace dying native plants with native species not currently growing in the arboretum
- Refinish the four benches
- Develop a plan with the SEA Club to further inspire students and faculty to use the native arboretum for educational, cultural and recreational activities
Resources
- Home | Sevenoaks Native Nursery
- Trees to Know in Oregon by Ed Jensen
- Shrubs to Know in Oregon by Ed Jensen
- Bessie Gragg Murphy. Botanizing in Benton County, 1900-1991. Soap Creek Valley History Project Oral Histories, 1978-2009 (oregonstate.edu)