This report was prepared for Reed College by ecologists Dennis O'Connor and Kendra Smith on November 19, 1999. Information about the current status of canyon restoration may be outdated.
Canyon Restoration Enhancement Strategy
Reed Canyon, within the Reed College campus and the headwaters of Crystal Springs, is in dire need of invasive species management and enhancement. The extraordinary water quality bubbling up from the springs around the canyon is in stark contrast to the ailing plant community complexes that dominate the system. The native trees and shrubs that form the overstory of the Canyon are at risk of being eliminated from the system, if the non-natives are left to spread unchecked.
This document, in conjunction with the graphic plans, outlines a management strategy for restoring and enhancing the canyon to a self-sustaining, ecologically balanced condition.
Management Units
Enhancement of Reed Canyon will be a slow methodical process of invasive species control and native revegetation. Segmenting the effort into several smaller projects will help the College move systematically through the enhancement process and remain ahead of the removal needs. It will also make the project more cost-effective and manageable.
Four management units were defined for the Canyon:
Location:Crystal springs canyon extends from the access road/ dam to the downstream edge of the property. The area is approximately 300,000 sq ft.
Condition:This area is a heavily used floodplain of crystal springs. The spring is piped under the road and extends 200' downstream, past a swimming pool before returning to the streambed. The culvert is impassable for fish. The riparian edge lacks vegetation and the southern side slope is dominated by an ivy understory. The theater extends out over the stream and there is heavy impact around the building footings, including erosion of the banks. There is little to no large woody debris in the stream, but spawning gravels are present and silt free. The trail needs further definition in some areas along the floodplain to reduce impact.
Vision:The southern slope supports a headwater forest community. The floodplain area to the north of the stream could be a mix of riparian edge community and forested wetlands. The pipe under the road and near the swimming pool could be pulled back and reconfigured to allow for fish passage and restoration of some channel bed. Riparian edge plantings could be used to direct specific access to the stream and reduce impacts to its banks.
Location:The Lower Lake extends from the pedestrian footbridge to the maintenance access road / lake dam. The area of enhancement is approximately 30,000 sq ft.
Condition:This area contains good native tree and shrub cover on the south side, with more sparse vegetation on the north side. The area contains the commons area on the south and dorm open space with lawn to the north. The level of invasive species invasion is similar to that of the middle lake, although the area is dominated by ivy in the understory and some non-native hawthorn. There is an area of potential emergent marsh directly across the lake from the commons area that is dominated by reed canarygrass. The trail in this area is in need of re-routing on the south side.
Vision:The southern side slopes support a headwater forest plant community that could be fully recovered with enhancement by extraction of natives and some revegetation. View corridors could be provided from the commons across the lake to an enhanced emergent marsh area on the north side. The grass area on the north side needs native plant revegetation to establish a more diverse buffer along the waters edge.
Location:The Middle Lake extends from the sanitary sewer line that crosses the Lake to the pedestrian footbridge. The area of enhancement is approximately 122,500 sq ft
Condition:This area contains good native tree and shrub cover, but the understory of ivy hinders the health of the area. Ivy covers the soil surface, out-competing native species and preventing them from establishing. Many of the ivy, as well as clematis vines extend high into the trees and may ultimately weaken and kill the trees. The flowering vines spread their seed throughout the area and down canyon. The trail is in need of upgrading, predominantly on the ground (rather than boardwalk). The middle lake offers a good chance of restoration success with persistence and relatively low cost. This area is visible from the bridge and appears to have moderate foot traffic.
Vision:The side slopes support a headwater forest plant community that could be fully recovered with enhancement by extraction of invasives. The first 10' closest to the water could support a riparian edge plant community that would adequately feed the beaver and protect the larger trees on site.
Location:The Upper Lake extends for the headwater headwater springs in the northeast and southeast end of the site, down to the sanitary sewer line that crosses the lake. The area is approximately 463,000 sq ft of upland with an additional 180,000 sq ft of open water / emergent marsh.
Condition:This area is dominated by reed canarygrass, nightshade and morning glory in the wetter portions of the site. Clematis, blackberry, and ivy dominate the upland areas. The upper lake will be the greatest challenge in invasive species management, and will require a variety of approaches. However the area is most critical, since wind and water will spread exotic seeds down canyon. The eastern and northern edge of the area is in need of buffering / screening from neighboring residents. The trail that goes around this area is in need of upgrading to elevated boardwalks to reduce pedestrian impact to water quality and risk of injury by those using the trail. This is the most isolated portion of the site, offering increased opportunity for the visitor to experience wildlife and solitude.
Vision:The spring fed portions of the site could easily support, an emergent marsh system with snags and basking logs in the open water areas. Along the edges of the marsh and in defined spring channels, a riparian edge plant community could be established. The uplands have the opportunity to support a headwater forest community, with understory and climbing vine invasive species control. There are also a few wetter areas that would support a forested wetland community.
Non-Native Species Management
Non-native species control in the Reed Canyon will require the use of an adaptive management strategy. Past impacts and surrounding landscaping have favored the dominance of invasive non-native species. Long-term management of these non-native plants will be necessary to restrict their spread into new areas and to reduce the existing populations. Revegetating areas with native plants will help to keep the invasive species from recolonizing bare areas.
By monitoring the success of each technique applied, Reed College staff will be able to scientifically assess when, where, why, and how additional efforts will be applied and managed. Maintenance of newly cleared or planted areas will also be necessary to ensure eradication and revegetation success.
The current site conditions (size, slope steepness, water quality conditions) dictate that an aggressive hand and mechanical removal program, combined with limited herbicide applications should be tried first. In the lake, mechanical removal of invasives will save time and energy. The steep bank areas with overstory will require the use of hand labor, by both professional and community stewards. Again, the key to success will be regular monitoring and maintenance of site conditions to ensure efforts will not be quickly undone by the undesirable species. The use of fire, solarization, biological controls and more intensive herbicide treatments are management measures of last resort for this site.
This section details information on the preferred management strategy for the different non-native invasive species found on site. Access for removal activities would include 37th Ave at the east end of the site and the pathways and maintenance access near the maintenance operations building. Management recommendations for the removal of specific non-native species from the Reed Canyon site are outlined below.
Both short and long term control measures should prioritize the following target species:
An introduced Eurasian species, Himalayan blackberry (Rubus discolor) is a weak-stemmed shrub often climbs over other vegetation, eventually crushing or smothering weaker species and forming formidable thickets. Along streams, the weight of the plant also causes erosion by pulling the bank down. Leaves are palmately compound, generally with five toothed leaflets. Sharp, flattened thorns are present on the leaves as well as stems. Flowers are white to pale pink, approximately an inch across, and bloom throughout the season. Berries are edible and tasty for humans, but few native birds / mammals forage the berries, diminishing its habitat value. The shrub reproduces both vegetatively by sending out runners and rhizomes, and by seed.
Reed Canyon and adjacent properties support extensive stands of Himalayan blackberry, which typically colonizes disturbed areas. They have formed patches in hummocks (low gradient islands) surrounded by water, and in drier portions of the site. Their canes and prolific berry production will continue to spread the plant throughout the site where conditions are favorable.
Recommended Management Strategy:
Physically remove large accessible plant masses (root and stock) with mechanized equipment in the summer, prior to berry production. Inaccessible areas and blackberry close to native plants can have canes removed anytime (early summer is most convenient).
Hand remove remaining stocks and roots in late winter. Repeat hand removal of new shoots in spring and late fall (after rains) annually. Properly dispose off site or burn dried canes on site. Roots must be removed from site.
Spot application of herbicide to remaining stocks to kill root over the winter (only in areas away from water and native vegetation). Rodeo or Vantage with a surfactant is recommended. Follow manufacturer's recommendation regarding application rate. Hand remove new shoots and roots in spring and fall.
Overseed cleared areas with sterile wheat or "Re-Green" to help reduce erosion of disturbed soil. Continue shoot removal until density is reduced to one shoot per 5 sq feet, or less.
Conduct annual monitoring and maintenance in early spring, summer and fall; hand pull new shoots and remove from site.
English ivy (Hedera helix) is an evergreen woody vine with thick, typically lobed leaves. Mature plants will eventually produce round clusters of small greenish flowers followed by black berries. The vines can cling to nearly any vertical surface using aerial rootlets that extend out from the stems. The plant's rapid growth upward into trees can ultimately shade the supporting tree to the extent that photosynthesis is affected, resulting in hampered growth. In addition, the increasing weight of the vines can eventually topple a tree that has been otherwise weakened by stresses such as root rot. The roots of the ivy tap into the cambium layer of some trees, depriving them of water and ultimately killing the tree. This characteristic makes it difficult to remove as the rooting can occur many feet above the ground surface.
This non-native vine has spread throughout the site over time, probably introduced as site landscaping or by berries from nearby residential landscaping. The ivy has developed into the dominant ground cover in most upland places and is infesting numerous trees as well.
Recommended Management Strategy:
Physically hand remove ivy from the ground and trees by cutting and pulling when the soil is soft enough to pull roots up. Carefully pull the roots and try to minimize breakage, otherwise the remaining root can re-sprout. Large vines that have climbed up in trees should be cut at the base and pulled from the tree once the ivy has died. If vines have rooted into the tree, use a ladder to climb the tree and break free the vine. If conducted during the winter, the vine can be pulled immediately without damaging the tree. Properly dispose of vines off-site or burn dried vines and roots on site.
Overseed cleared areas with sterile wheat or "Re-Green" to help reduce erosion. Rake disturbed areas smooth before re-seeding. Continue vine removal until density is reduced to one shoot per 5 sq feet or less.
If necessary, a broadcast spray of herbicide may be applied after the leaves have been string line trimmed and raked out, but only in areas where there are no native species. Breaking the leaf edges allows for a better application of herbicide. Spot apply until eradication is complete. Herbicide is not effective on leaves that have not been cut opened. It is best used to kill the roots and new shoots.
Conduct annual monitoring and maintenance in early spring; hand pull new sprouts.
English hawthorn (Crataegus monogyna) is a small deciduous tree that has 1.5" deeply lobed leaves that resemble tiny oak leaves, and thorns on its bark. It produces an abundance of red berries in the late summer that the birds help to transport. It can form dense thickets and out compete other small native trees. The native black hawthorn has similar form, but its leaves are oblanceolate with serrated edges rather than lobed.
There are several scattered locations at Reed Canyon where this species is found. Removing it from the site now will help prevent problems with their management in the future.
Recommended Management Strategy:
Hand remove by clipping the stock to 6". Grub out the roots or treat the remaining stock with a brush on herbicide to kill the roots. Properly dispose of plant off-site or burn stocks on-site.
Hand pull any new growth in treated areas when found in spring. Do not allow plant to seed.
Clematis (Clematis vitalba) is a woody, deciduous, semi-shade tolerant perennial vine. It is particularly common in disturbed open canopy areas of riparian and deciduous woodlands. Its rapid growth (up to 20 feet per year) tends to smother the ground and the plants it has attached itself to. When the vine extends up into trees and shrubs, it produces an abundance of wispy flowers that eventually seed and spread the plant downwind. The heavy weight of the vines eventually damage or fall the trees and shrubs from which it hangs.
Clematis in the Canyon is found throughout, but is heavily concentrated in the upper lake and on the northern slopes, within the trees. The plant is also on adjacent landowner trees.
Recommended Management Strategy:
Initial efforts should focus on removal of mature flowering vines from the trees. Plants should be cut close to the ground, and removed once the tree has gone into dormancy for the winter. Roots of the vine around the trees should also be pulled when the soil is moist and properly disposed of off-site or burned on-site. The use of herbicide should be avoided due to potential damage to the native trees and shrubs with the use of herbicide.
Hand pull any new shoots and remove from site.
Work with neighbors to remove plants from trees bordering the Reed Canyon property.
Nightshade (Solanum sp.) and morning glory (Ipomoea sp.) occupy similar environments and are similar in form. They are rhizomatous perennial non-natives with a persistent woody base. Introduced from Asia and Europe respectively, these plants prefer the moist habitat along the edges of wetlands, ditches and riparian corridors (morning glory likes it slightly drier). Nightshade has dark green heart-shaped leaves that often have one to several leaflets at the base. It has a star-shaped purple flower with a yellow center that is followed by a bright red berry that contains abundant tiny seeds. Morning glory has lighter heart-shaped leaves and a large white tulip-like flower.
Both these species are found in abundance throughout the upper lake area both in the wetland areas and upland fringes.
Recommended Management Strategy:
Repeated cutting via flail mowing or string line trimming followed by raking of remaining plant material is recommended. Debris should be picked up and burned or otherwise disposed of off-site, since stems easily propagate from cuttings. Cutting should be carried out before the plants flower to reduce the spread of seed.
Grubbing of the roots by hand is difficult due to the rhizomes nature, so mechanical (backhoe) removal of the soil, where possible should be attempted. Solarization of the ground around the infestation should be attempted where mechanical removal of the root mass is not possible.
Herbicide treatment is not recommended for these plants due to the close proximity of their roots to native trees and shrubs, and water. The herbicide may be translocated to the native plants or impact water quality.
Hand pull any new shoots and remove from site.
Reed canarygrass (Phalaris arundinacea)forms a dense mat of grass that can tower as high as 7 feet high in both wetland and moist upland areas. This perennial grass spreads by rhizomes as well as by seed. This grass is common throughout the upper reaches of Reed Lake, but has yet to spread to the lower lake and crystal springs canyon. It is believed that the reed canarygrass requires the formation of islands of sediment to successfully establish in open water environments. The clear waters of Crystal Springs carry very little sediment, making the formation of sediment hummocks in the middle and lower reaches of the lake slower than expected.
Reed canarygrass is dominant in the aquatic portion of the upper lake and in limited areas on the fringes of the lower lake.
Recommended Management Strategy:
Small patches may be controlled by string trimming in the early spring prior to the plant setting seed. As the plant is weakened, it may be dug out of the ground.
Large infestations require mechanical removal in order to remove the mat. For this site, it would be best to conduct the aquatic component in the winter with the use of an aquatic weed harvester. The level of the water would need to be elevated to approximately 3' depth to use such equipment, but it offers a promising result with limited impact to water quality or the bottom sediments of the Lake. The removal may need to be repeated to significantly reduce the infestation. The edge areas would need a small backhoe and should be removed in the summer. The stocks should be string trimmed to eliminate the seed head production, prior to the mat removal later in the summer.
Spot application of herbicides may be done in non-wetland areas during the summer months. Rodeo and vantage are recommended in the non-wetland areas at the manufacturer's recommended application rate. In wetland areas, new shoots should be dug out and removed from site.
The reed canarygrass mat should be hauled up to a dewatering area, and then properly disposed of off-site.
Teasel (Dipsacus fullonum) and thistle (Cirsium sp., Carduus sp.)are rapid spreading colony forming herbaceous weeds that use wind and pollinators to spread their seeds. Teasel has a 4-6' tall armored stalk with a cone-like purple flower and seed head that turns brown in late summer and is persistent throughout the winter. Thistle is 2-3' tall with needle-like armor and a seed/flower head that looks like a purple upside down cap. Both species are limited on site, but should be controlled early to avoid greater levels of infestation. They quickly invade disturbed soil and prefer drier conditions.
Recommended Management Strategy:
String trim stalks in early summer when the plants are in between flower bud and seed stage. Carefully remove stalks and burn or dispose off-site.
Apply wick application of herbicide to the remaining rosette.
Native Plant Revegetation
When the management of invasive vegetation in a given area is under control, enhancement by addition of native plant materials can begin. Where proposed, habitat creation in the form of snags and downed large woody debris should be created or imported prior to planting so that access to the site is clear. The following is a list of enhancement elements to be considered, followed by specific plant community lists for revegetation of Reed Canyon.
Soil preparation will be based on what is found following the removal of invasive species. Some areas may require minor soil amendments, but it is likely only in limited circumstances.
Recommended Management Strategy:
Upon completion of invasive species removal determine the levels of soil amendments needed, if any.
Use only weed-free soil additives such as mature leaf compost, to reduce further invasive species contamination of the site.
Use gypsum if dense soils need to be amended for better drainage of water.
Creating additional habitat at the site will require the import or movement of large woody debris. Habitat features should be added once invasive species are under control and before native planting are added.
Recommended Management Strategy:
Maintain standing and downed woody debris on site for cavity nesters and as basking logs for turtles.
Add bat and bird boxes throughout the site, on the edge of transition habitat areas.
Import additional large woody debris if available and as needed.
Planting of the different management zones will occur as areas are cleared of invasive species and appropriately prepared. Successful revegetation of the site will require proper propagation, installation, maintenance and monitoring of the existing and newly installed plant material.
Recommended Management Strategy:
Planting is best during the late fall, winter, and early spring. Seed during the late summer/early fall or early spring.
Heal-in plant material to site for several weeks prior to planting by placing it in the area in which it will be planted; propagate plant material on-site if there is interest in doing so.
Provide topsoil mix in planting hole if soil conditions are poor; topdress all plantings with mature leaf compost to provide nutrients and protect from dry out (particularly in sunny locations).
If beavers are an issue, surround plants with welded wire guards to keep them from damaging new plantings or larger existing trees.
Provide erosion control as needed by seeding ground with sterile wheat or re-green or the native seed recommended. Some areas may require soil bioengineering techniques.
Deep water plant material 5-8 times per summer for the first two to three years, or longer if needed.
Weed around new plantings at least twice a year, and place additional mature leaf compost.
The following is a list of suggested plants by their community type. To see photos, habitat requirements, and taxonomic information for the plants listed below, please visit theCalFloradatabase.
Open Water / Aquatic Zones Wapato (Sagittaria latifolia) American water plantain (Alisma plantago-aquatica) Watershield (Brasenia schreberi) Water smartweed (Polygonum amphibium) Yellow pond lily (Nuphar lutea ssp polysepala) Marsh cinquefoil (Potentilla palustris)
Headwater Riparian Forest Zone Red alder (Alnus rubra) Western Red Cedar (Thuja plicata) Western hemlock (Tsuga heterophylla) Big leaf maple (Acer macrophyllum) Douglas Fir (Pseudotsuga menziesii) Cascara (Rhamnus purshiana) Pacific dogwood (Cornus nattallii) Vine Maple (Acer circinatum) Red elderberry (Sambucus racemosa) Red-osier dogwood (Cornus stoniferia) Indian plum (Oemleris cerasiformis) Baldhip rose (Rosa gymnocarpa) Snowberry (Symphoricarpos albus) Salmonberry (Rubus spectabilis) Sword fern (Polystichum munitum) Cascade Oregon Grape (Mahonia nervosa) Tall Oregon Grape (Mahonia aquifolium) Salal (Gaultheria shallon) Thimbleberry (Rubus pariflorus) Woods Rose (Rosa woodsii) Serviceberry (Almelanchier alnifolia) Wood strawberry (Fragaria vesca) Blue Wildrye (Elymus glaucus) Skunk cabbage (Lysichitum americanum) Idaho or Oregon bentgrass (Agrostis idahensis or oregonensis)
Special Areas
There are several areas at Reed Lake Canyon that warrant special attention and more specific plan implementation than just invasive species management and revegetation. They are outlined below and graphically depicted in the plans.
This area is located in the northeastern most edge of the site, at the start of one of Crystal springs. A berm was installed to create a pond, and has since been breached by the water. A deep gully has formed and a small makeshift bridge goes across the gully
Recommended Management Strategy:
Following the removal of the invasive species from the area, re-grade the berm, to re-create a shallow pond on the eastern edge.
Repair the gully by creating a decorative rock waterfall feature that will cascade the water out of the pond.
Install a bridge over to top of the waterfall feature to re-establish safe pedestrian passage through the area.
The upper lake has several areas along its eastern and northern boundary that are in need of buffering. Non-native plants from private residential sites need to be blocked and not allowed to migrate on site.
Recommended Management Strategy:
Work with neighbors on the northern property boundary to re-establish a headwater forest slope, and reduce the invasion of non-native plants from their yards on to college property. Establish a 10-foot wide thicket of native vegetation to buffer the area from the neighboring property.
Establish a 30-foot wide thicket of willow, and black cottonwood along the eastern boundary in the wetland areas, to block migration of invasive species from the private residence with the pond.
The commons area along the south side of the lower lake overlooks the lake towards the north and is a focal point for gatherings. The plant material on the south side should not obstruct the view of the lake. The northern bank of the lake is in need of enhancement to beautify the views.
Recommended Management Strategy:
Use only native shrubs and groundcover in the commons area, so as not to eliminate views of the lake. Choose plant species that offer a variety of color and texture, especially in the fall.
Remove reed canarygrass from wetland edge on the north side and reestablish an emergent marsh environment. Choose plant species that offer a variety of color and are attractive to wildlife.
The lake is maintained by an earthen dam across the canyon, with an access road crossing over the top. A long culvert extends from the lake to the creek below, past the swimming pool that is placed within the filled zone. Fish cannot pass through the culvert due to its slope and the vertical drop from the concrete pipe spillway to the creek bed. A desire to restore fish passage through this area has been expressed and may soon be required under the Endangered Species Act.
Recommended Management Strategy:
Conduct a detailed survey of site conditions (fill type, elevations, and location of the pipe)
Develop a plan to cut back the pipe or replace it with a box culvert
Excavate a narrow canyon to the north of the swimming pool to recreate a stream channel with step-pool sequencing, so that the fish can migrate up into the lake. The total channel enhancement is approximately 250 ft.
Revegetated the canyon / new stream channel with riparian forest plantings
Move the access trail down to the floodplain area to the north, so as not to conflict with the stream rehabilitation.
The school theater was built over Crystal Springs Creek. There is a fair amount of erosion of the stream bank near the pilings of the building as well as underneath it. Heavy pedestrian traffic in the area has compacted soils throughout the area.
Recommended Management Strategy:
Stabilize the stream banks using bioengineering techniques (willow and dogwood pole cuttings)
Cut-off access underneath the building structure by planting Nootka rose, willow and red-osier dogwood
Excavate the banks under the structure down to a level where the soil remains saturated. Stake pre-planted mats of small fruited bulrush and slough sedge into these excavated areas
Add large woody debris throughout this stream reach to restore in-stream habitat complexity
Add a second stream crossing on the downstream side of the theater to provide access to the trail that goes up to the entry road
There are both soft and hard surface trails throughout the campus. The current trail around the lake and into the stream canyon area is in need of repair and relocation in some instances.
Recommended Management Strategy:
Survey trail location and identify new routs that are more environmentally appropriate. Re-route the trail a minimum of 15 feet from the edge of the lake or stream where possible
Create trails that are a minimum of 3 feet wide and relatively flat in grade and cross slope.
Install elevated boardwalks in wet areas (3 feet wide minimum) to reduce impacts to water quality and species migration, and provide for safe pedestrian passage
Maintenance, Monitoring, and Stewardship
The site will need continuous monitoring and maintenance as the enhancement activities are underway. Several areas at the site are conducive to stewardship opportunities, but a majority of the effort will ultimately be the responsibility of the Physical Plant department. Due to the size of the site and level of enhancement needed, dedicating at least one staff member to keeping the enhancement activities on task will be necessary. Without dedicated site staff, the implementation of this management plan and the long-term maintenance and monitoring will not be timely or adequate. Promotion and encouragement of stewardship is an ongoing and timely activity that requires consistency in staffing.
Secure an endowment fund for Reed Canyon that includes long-term maintenance and monitoring needs.
Allow native plant revegetation per the management zone species list, only when invasives are under control.
Establish a set of digital photo points within each management zone; take photos before, and each year after for three years to monitor progress of enhancement activities. Store site locations on a digital / GIS map and record data information in excel spreadsheet.
Prepare a yearly update of progress, with before and after photos and a schedule of upcoming events, in order to keep people informed and engaged, and for continued funding support.
Revisit enhanced areas on a regular basis to track progress and keep ahead of any re-infestation by non-native species. Keep information in a database with dates and conditions.
Establish success criteria such as: 80% revegetation survival of natives; 90% presence of native plants and less than 10% invasive species presence in a given enhanced area.
Inform all participants of the proper removal techniques prior to commencing work.
Limit activities to those that are safe for appropriate individuals to participate. The appropriate labor force for each area is dependent on topography, time of year, and diligence of the people to protect native plantings. Limit hand removal of invasive species by untrained individuals to flat / moderately sloped areas. Allow trained students and hired crews/professionals to conduct removal on more difficult terrain.
Develop a web site or link for the Reed Canyon to publicize events and activities, keeping neighbors and students informed and active.
Maintain a list of volunteers that participate in site activities in an Access database. Send direct mailers to those volunteers when an event is scheduled.
Allow committed volunteer groups to adopt certain enhancement areas. Request that they sign a commitment form for two years to help reduce turnover.
Participate annually in SOLV programs to gather off site assistance with the effort
Encourage the development of a "Friends" group for the Canyon that includes current students and Alumni. Hold an annual "ivy pull".
Enlist professors and their students to assist with monitoring efforts as part of class curriculum. Expand their efforts to maintenance as appropriate.