At the present time, the riparian corridors along the central campus show the effects of both long term lack of ecological management and heavy use. Overall, there has been a drastic reduction in both animal life as well as the ecological integrity and diversity of these riparian areas. Many exotic (non-native) species have been introduced into areas that were once exemplars of native vegetation. In addition, manicured institutional landscape management techniques have been previously applied to the natural areas resulting in the disturbance of these ecosystems. Although an urban campus cannot be expected to maintain truly wild settings, there is a need and use for natural areas for instructional, aesthetic, and ecological reasons. In their present condition, the riparian areas have not fulfilled their potential as a valuable teaching/learning or ecological resource.
In 1969, the University permanently established the Goodspeed, Grinnell, and Wickson "natural areas" along Strawberry Creek on the central campus (Figure 22). These three areas were dedicated to preserve "green space" on an increasingly urbanized campus and to protect and satisfy instructional needs in the natural sciences. In 1970, the Landscape Architecture Advisory Subcommittee (LAAS) renamed the central campus natural areas "nature areas" in recognition of the fact that these areas were not at all "natural." These nature areas may also be referred to as "ecological study areas."
In 1970, the LAAS recognized that a management policy of almost total neglect was neither appropriate or accomplishing the original objectives, and subsequently formulated recommendations for management appropriate to the nature areas. Their goal was to structure a program that would preserve wildlife habitat while enhancing the ecological integrity of the plant communities. However, these guidelines were never implemented because no funds were allocated and their recommendations faded into obscurity after the LAAS was phased out in the mid-1970's. Subsequently, the Committee on Conservation and Environmental Quality (CCEQ) formulated management recommendations which have remained in draft form to the present time. The following recommendations pertaining to the central campus nature areas are based upon the original LAAS Task Force recommendations and subsequent CCEQ management guidelines.
The following general guidelines should be considered in the management of the nature areas:
- Nature areas should be clearly defined and accorded the same stature as other teaching and research facilities.
- A faculty advisory committee should be formed to oversee long-term management and enforcement of guidelines.
- A detailed management plan that includes a public education program should be formulated for each nature area
- Emphasis should be on replacing exotic (non-native) vegetation with indigenous plants over an extended period
- Exotics could then be cut out gradually. Stripping of vegetation should be avoided. Some introduced native vegetation (such as redwoods) will have to be thinned or removed in appropriate areas to open up the understory for the establishment of a more di verse natural habitat
- Restoration of native vegetation should be limited to the species listed in Appendix C.
- Native plant communities should be enhanced by the planting of appropriate understory and groundcover species as indicated in Appendix C. Concerns over security in these areas can be accommodated by the use of low-growing vegetation such as herbs and forbs in the redwood stands. In addition, discrete and skilled management along with barrier plantings should mitigate any concerns over safety.
- Biotechnical streambank stabilization methods as outlined in Section 5.1.2 should be used where appropriate rather than structural methods.
- A system of informational signs should be provided to inform the public of the management techniques and for species identification.
- The UC Botanical Garden and campus nursery should be utilized to propagate native vegetation.
- Detrital material such as dead trees and decaying ground cover should be left in place unless it poses a safety hazard to enhance wildlife habitat and allow for the study of natural processes.
- Diversity of vegetation should be maximized within the limits of appropriate native plants.
- No spraying should be allowed except as absolutely necessary.
- Appropriate paths should be laid out to reduce disturbance and compaction.
- Plants, animals, or other materials should not be removed from the nature areas without permission of the faculty committee.
- Rock clusters should be introduced in certain areas for habitat diversity.
- Groundskeepers should be trained in ecological management techniques and supervised by the campus Landscape Architect or another person trained in natural landscape management.
- A walking tour of the central campus should be established for public education and enjoyment of the nature areas.
- A review mechanism should be provided to assess the impacts of proposed campus development or other changes in the natural landscape.
The following recommendations pertain to the specific nature areas:
Goodspeed Nature Area
- This nature area lies in the heart of a formally landscaped, heavily used portion of the campus so this area will need to be compromised between a natural and more formally developed landscape more so than the other nature areas.
- Area west of Church footbridge is basically cultivated and should remain so.
- Dead limbs and shrubs should be removed in the area west of Church Bridge and thinning performed as plants become overcrowded and overshaded. The arrangement and trimming of plant material in this area should permit views of the creek and environs over the groundstory planting and under the tree canopy.
- Understory west of Church Bridge should be enhanced with redwood associates due to the stand of mature redwocxis present here.
- The rhodcxiendrons and azaleas east of Church Bridge are nearing the end of their life span. These shrubs and other invasive understory vegetation should be phased out and replaced with native plants. The various non-invasive understory plants should be preserved for botanical and aesthetic variety.
- Middlestory plantings east of Church Bridge should remain high (10 feet or more) to preserve the backdrop and privacy of Faculty Glade.
- Diseased and declining trees east of Church Bridge should be phased out and replaced with native riparian species.
- Streamside border plants such as sedges, horsetail, and water parsley should be preserved and enhanced as they rarely grow downstream due to scouring of the channel.
Grinnell Nature Area
- The Eucalyptus Grove should be enhanced through tree maintenance and replacement.
- Fallen trees should be left alone and vegetation remain thick to provide a solid border to the Eucalyptus Grove and creek.
- The LeConte Pine Grove area should remain in an uncultivated condition. A few dead pines and oaks should be left both for visual interest and educational purposes unless they pose a safety hazard or interfere with healthy growth.
- Invasive species and diseased shrubs should be removed form the Pine Grove area. Overcrowded and overshaded vegetation should be thinned in favor of the pines and oaks. Native grasses should be planted here as this is one of the only amenable habitats on the central campus for grasslands.
- The Oak Grove south of LSB should be enhanced by tree maintenance and replacement. The Grove and oak leaf mulch ground layer should remain as is. Additional varieties of beech could be planted north of this Grove for teaching purposes and to extend the life of the Oak Grove.
- Creekside planting should be cleared of invasive species which are dead, diseased, or interfering with more important native species. Shrubs should be kept solid but trimmed to prevent overcrowding or interference with specimen native vegetation.
Wickson Nature Area
- In the area between Wickson Road and the University House footbridge by Haviland Hall invasive species should be phased out and replaced with redwood associates.
- All trees and shrubs south of the footbridge should be pruned to allow light penetration for understory growth. Weak specimens that have been overcrowded or overshaded should be removed.
- The variety of plant species south of the footbridge should be preserved and the various specimen trees enhanced by careful trimming of the plants around them.
- The creek south of the footbridge should be about 50% visible, and shrubs should not be higher than eight feet.
- The area between the footbridge and North Gate has a less cultivated appearance and should remain this way.
- Diseased trees and overcrowded specimens north of the footbridge should be removed. Important trees should be pruned and encroaching plants trimmed.
In creek areas outside the nature areas, exotic vegetation should be permitted to maximize the diversity of the campus landscape. These areas already contain a number of exotic species which serve to attract birds and other wildlife that would not ordinarily inhabit these areas. Exotics may be planted along the North Fork from University Drive to the West Circle and along the South Fork from Cross Campus Road to Stephens Hall. Aging and stagnant plantings should be renewed to enhance the appearance and functionality of these areas.