Ecology of the Canyon
by Bruce Moreira, Reed '97
The following article was published in the 1995 Green Board Audit. Copyright ©1995 Reed College
This article is being published as a historical reference. Some information may no longer be current.
Transecting the middle of the Reed College Campus property, the Reed Canyon is fed by at least two springs which come from the Portland Terraces. It drains into Crystal Springs through the Rhododendron Gardens and then to Johnson Creek and eventually the Willamette, Columbia and finally the Pacific. Before housing development east of the college campus, it is believed to have reached up 41st Ave. The body of water in the canyon predates Reed. Since the development of the College, it has become more sedimented and less of a river than a lake. It has been the subject of many studies and most recently a Natural Sciences course lab series. In 1938, Una V. Davies described it as "little cultivated or parked" but far from being a native ecosystem it is a wild "garden" which consists primarily of native species yet is infested with introduced species from the campus cultivated areas and from neighboring houses.
The canyon is currently characterized by the presence of a host of introduced species as well as native ones. Much of the tree life consists of Red alder (Alnus rubra), Douglas fir (Pseudotsuga menziesii), Bigleaf maple (Acer macrophyllum), and Western red cedar (Thuja plicata). On the south side of the canyon much of the undegrowth consists of English ivy (Hedera helix), Sword fern (Polystichum munitum), and a diverse array of bushes, grasses, and herbs, such as Indian plum (Oemleria cerasiformis) and Black hawthorn (Crataegus douglasii). On the north side, there are more grasses, areas of heavy Himalayan blackberry (Rubus discolor) coverage as well as some Ivy covered areas. The north-side has much less tree coverage then the south. There is a moderate diversity of flowering herbs, such as Honesty (Lunaria annua) and the Spring beauty (Dentaria tenella). Also there is a diversity of ferns including a tiny population of the small and less common Golden-back fern (Pityogramma triangularis). Many of the species found, such as English ivy, are clearly present because of intentional introduction by the college or by escape from the surrounding area. Some of these, however have interesting stories behind them, like the Kalopanax pictus, a large yet nondescript tree just behind the Chemistry building native to eastern Asia which was planted by Dr. Bert Brehm to commemorate the Arnold Arboretum Centennial Celebration in 1972.
Much of the ecological change of the canyon described in this paper is based on a thesis completed in 1938 by Ms. Una V. Davies entitled "Vascular Plants of the Reed College campus." Many of the species she cites as being in the "canyon" are still abundant, like Trilliums (Trillium Ovatum), Sword ferns and Douglas firs. Others have apparently disappeared, like the Triangular Wood fern (Dyropteris apinulase), and Smith's fairybells (Disporum smithii). The most striking change however are the species which were not present, or very limited in 1938, but are widespread now, most significantly; English ivy (Hedera helix), Himalayan blackberry (Rubus discolor), Wild clematis (Clematis ligusticifolis) and English holly (Ilex aquifolium), and two decorative garden flowers, Honesty (Lunaria annua) and English wood hyacinth. Both the Ivy and the Holly are listed in Davies' thesis but she indicates that they are limited to a few locations on campus as cultivated species. The Himalayan blackberry receives no mention in her thesis, and judging by her rigorous and systematic search, it is safe to assume that it was not present. All five are now among the most common and widespread flora of the canyon, English Ivy being the most prominent, though the blackberry is a far greater nuisance because of its thorns and density. Both the Ivy and the blackberry have been targets of significant clearing efforts by the College Physical Plant and volunteer students. Honesty and the English wood hyacinths are obvious examples of "escapes" from the surrounding house's gardens, as they are strictly found in peripheral parts of the canyon in dense columns leading back to the yards of houses abutting the canyon. In on case, the English wood hyacinth can actually been seen in the garden of the house. These two flowering plants are very different than the ivy, holly, and blackberry in that by the standards of many students and other users of the canyon, their attractive and showy pink and purple flowers provide a beautiful bloom in the spring (which is of course why they came from gardens). No suggestion has been made to clear these species out, like the blackberry, or ivy and there is little evidence that they are shading out other species.
Though this assessment is admittedly biased towards flora to the canyon, there are also a large number of birds, a few mammals, and one species of amphibian. The most heavily studied species of the canyon is the terrestrial Oregon salamander (Ensatina eschscholtzi oregonesis). This small orange bellied salamander can be found by anyone wiling to forage through damp underbrush on the southeast side of the canyon and has been the subject of numerous thesis under Dr. Bob Kaplan, and even more smaller independent projects for Dr. Kaplan's Population Biology lab. However, according to Dr. Kaplan, there are no other species of amphibian in the canyon. It is unknown what type of aquatic life is present in the lake, but great blue herons and kingfishers have been seen foraging in the canyon which would imply the presence of fish. Dr. Tom Dunne has seen fish in the water and Nik Manoukis, a biology student, recently caught Sticklebacks (Gasterosteus spp.) for an upcoming summer project.
The Chemistry Department's assessment of the canyon showed that it is basically clean and healthy but may be in danger of silting up or possibly even running dry. Dr. Tom Dunne's chief concern about the canyon is that it could run dry in dry years because of pumping from local wells. It is unclear how much water is being pulled out of the springs which feed the canyon, but the flow rate dropped by 75% during a period in which the city had limited municipal water distribution. Here is a quick break-down of the numbers produced by Dr. Dunne and his Natural Sciences class.
|Reed Lake Statistics|
|Phostphate content:||0.08 mg*P/L (average)|
|Nitrate content:||5.45 mg*N/L (average) (well below EPA standards)|
|Oxygen content:||saturated at surface, 69% saturation at 1.5 meters|
|Mineral content:||87 mg*CaCO3/L (hard)|
More information and details on the canyon's chemistry will be available in a paper to be produced by Dr. Dunne this summer. [Web Publisher's note: The papers produced by the Nat Sci classes in 1994 and 1995 are now available on the web.]
Geography: The canyon is crossed by a network of trails and makeshift bridges as well as the large cement walking bridge which connects the dormitories on the north-side of the campus to the south-side of the campus. At the wide east end, the canyon covers half the breadth of the campus and is mostly undeveloped. The soil in this area is very soft and moist and the land flat. Much of this area is a semi-flooded swamp with a networks of streams. Along the edges of the canyon, the walls steepen and gain up to 40 feet before hitting development from the College. They never get steep enough for sheer drops, however. These areas, as well as the rest of the canyon, are heavily covered with trees and shrubs. At the west end, just below the physical plant the canyon is transected by a College-built land bridge with a small culvert which diverts the canyon about 50 yards to the west where is continues unobstructed until it passes under 28th Avenue at the west border of the campus.
The canyon lake is extremely silted and more accurately termed a swamp at the east end. In the past, the west end was used as a "swimming hole" but that activity has ceased. It has been prone to Algal blooms during times of drought. After it passes through the culvert by the Physical Plant, it takes the form of a small rapidly moving stream.
The listings below must be qualified with these reminders. No effort was made to systematically identify any non-plant organism in the canyon, and all identifications were made when performing the flora census , during other activities, or through other references which cited the species' presence. Little effort was made to identify monocot grasses, moses and other bryophytes, late budding trees and flowers, and a few extremely difficult to key species because of time constraints. All the bird species sighted were supplied by Dr. Johnny Powell and by myself and are simply the birds we happened to have seen in the canyon. In short, these are extremely incomplete lists and are not meant to be the last word about what is in the canyon and may contain some incorrect indentifications.
If anyone reading these pages has any information to add to these lists, I welcome it. You can contact me via email (firstname.lastname@example.org) or leave messages in box 993. In the future, these lists will be expanded to be more complete and accurate.
FLORA OF THE REED CANYON
Red Alder (Alnus rubra) CR
Douglas Fir (Pseudotsuga menziesii) AR
Big Leaf Maple(Acer macrophyllum) CE
Western Red Cedar (Thuja plicata) CE
English Ivy (Hedera helix) AE I
English Holly (Ilex aquifolium)AE I
Black Hawthorn (Crataegus douglasii) CE
Himalayan Blackberry (Rubus discolor) AR I
Pennsylvania Bittercress (Cardamine pensylvanica) CE I
Fringecup (Tellima grandiflora) CE
Dandilions (Taraxacum officinale) CE
White Weedy Mustard AE I
Sword Ferns (Polystichum munitum) AE
Lady Fern (Athyrium filix-femina) AE I
Common or Field Horsetail (Equisetum arvense ) AG
Bedstraw (Galium trifolium) AE
|Region A: Northwest Shore
|Region B: Northeast Shore
|Region C: East-End Marsh
|Region D: Southeast Shore
|Region E: Southwest Shore
|Region F: West-end StreamBanks
Frequency: A=Abundant C=Common S=Scarce
Distribution: E=Evenly G= Grouped R=Regionally
Notes: I = Recent Colonizer
FAUNA OF THE REED CANYON
Beavers (4 at last count)
Nutria (occasional from Rhododendron gardens)
Oregon Salamander (Ensatina escholtzi oregonesis)
Wood Duck (Aix sponsa)
Mallards (Anas platyrhynchos)
Hood Merganser (Lophodytes cucullatus)
Common Merganser (Mergus merganser)
Bufflehead (Bucephalla albeola)
Ruddy Duck (Oxyura jammaicensis)
Green Winged Teal (Anas crecca)
American Widgeon (Anas americana)
American Coot (Fulica americana) suspected
Canada Geese (Branta canadensis)
Belted King Fisher (Ceryle alcyon)
Great Blue Heron (Ardea herodias)
Green-Backed Heron (Butorides striatus)
Hairy Woodpecker (Picoides villosus)
Northern Flicker (Colaptes auratus)
Western Wood Pewee (Contopus sordidulus)
Barn Swallows (Hirundo rustica)
Violet-green Swallows (Tachycineta thalassina)
Northwestern Crow (Corvus caurinus)
Scrub Jay (Aphelocoma coerulescens) ??
Stellar's Jay (Cyyanocitta stelleri) ??
Black-capped Chickadee (Parus atricapillus)
Chestnut Backed Chickadee (Parus rufescens)
Bushtits (Psaltriparus minimus)
House Wren (Troglodytes aedon)
Bewicks Wren (Thryomanes bewickii)
Ruby-Crowned Kinglet (Regulus calendula)
Robin (Turdus migratorius)
Varied Thrush (Ixoreus naaevius)
Orange Crowned Warlbers (Vermivora celata)
Song Sparrows (Melospiza melodia)
House Sparrows (Passer domesticus)
Rufous-sided Towhee (Pipilo crissalis)
Dark-eyed Junco (Junco hyemalis)
House Finch (Carpoodacus mexincanus)
Evening Grossbeak (Coccothraustes vespertina)
American Goldfinch (Caarduelis tristis)
Starling (Sturnus vulgaris)
Kildeer (Charadrius vociferus)
Western Gull (Larus occidentalis)
Glaucous Gull (Larus hyperboreus)
Glaucous-winged Gull (Larus glausescens)
American Kestrel (Falco sparveris)
Owl (exact spp. unknown)
Sharp-shinned Hawk (Accipiter striatus)
Turkey Vulture (Cathartes aura)
Since this Audit's survey was only conducted during the months of March and April, many of the species which Una Davies indicated to be present have not begun their seasonal growth nor flowered and thus went unnoticed. Indeed, every time another tour of the canyon was conducted to confirm the presence of certain species, at least one more flowering herb was found. In an attempt to be more complete, I have decided to err on the side of overrepresentation and include the following list which is taken directly from Davies' thesis. I also included all the grasses, sedges and rushes since I did not attempt to identify them independently.
These plants are those which she listed as present in the "canyon" portion of her survey and have not been confirmed for fifty-seven years. All of the species in the previous list were present in her survey unless marked as "recent colonizers". In the upcoming year, an attempt will be made to more completely confirm the presence of the species listed below. Some of the species listed in her thesis have since changed names and I have listed them under their most recent names as listed in Hitchcock and Cronquist.
Other Possible Flora of Canyon (from Davies, 1938)
Grasses, Sedges and Rushes
Common Cattail (Typha latifolia)
Wheat Grass (Agropyron caninum)
Quackgrass (Agropyron repens)
Ripgut Grass (Bromus rigidus)
Drooping Wood Reed (Cinna latifolia)
Western Fuscue (Festucs occidentalis)??
Tall Manna Grass (Glyceria elata)??
Velvet Grass (Holocus lanatus)
Italian Rye (Lolium multiflorum)
Perennial Rey Grass (Lolium perenne)
Alaska Onion Grass (Melica subulata)??
Fowl Blue Grass (Poa palustris)
Nodding Tristem (Tristem cernuum)??
Awl Fruited Sedge (Carex stipata)
Sedge (Carex spp.)
Duckweed (Lemna minor)
Common Wood Rush (Luzula campestre)
Small flowered Wood Rush (Luzula parviflorum)
Rush (Juncus spp.)
Fairy Bells (Disporum oreganum)
Smith's Fairy Bells (Disporum Smithii) ?
Wild Lilly of the Valley (Maianthemum bifolinm) ?
Slim Solomon's Seal (Smilacina sessilifolia) ?
Fat Solomon's Seal (Smilacina amplexicaulis) ?
Water Pepper (Polygonum hydropiperoides)
Lady's Thumb (Polygonum persicaria)
Bitter Dock (Rumex obtusifolius)
Lamb's Quarter (Chenopodium album)
Miner's lettuce (Montia sibirica) different???
Sandwort (Arenaria macrophylla)
Pink Sand Spurry (Spergularia rubra)
Chickweed (Stellaria borealis)
Benneberrry (Actaea spicata)
Woods buttercup (Ranunculus bongardii)
Vanilla Leaf (Achyls tryphlla)
Inside-out flower (Vancouveria hexandra)
Charlock (Brassica arvensis)
Charlock, Jointed (Raphanus raphanistrum)
Water Cress (Rorippa Nasturtuim-aqusticum)
Bishop's Cap, Leafy-stemmed (Mitella caulescens)
Gooseberry, Straggely (Ribes divaricatum)
Coolwort Three-leaved (Tiarella trifoliata)
Youth-on-age (Tolmus mensiesii)
Service Berry (Amelanchier slaifolia)
Wood Strawberry, (Fragaris bracteata)
Large-leafed Arvense (Geum macrophyllum)
Wood Rose (Rosa gymnocarps)
Aliske Clover (Trifolium hybridum)
Vetch (Vicia americana)
Narrow Leaved Vetch (Vicia angustifolia)
Suksdorf's Sorrel (Oxalis suksdorfii) ???
Water Starwort (Callitricha palustria)
St.Johns-wort (Hypericum forosum var. scouleri)
Willow Herb (Epilobium adenocaulon)
Fireweed (Epilobium angustifolium)
Enchanter's Niightshade (Circaea pacifica)
Western Water Hemlock (Circuta douglasii)
Poison Hemlock (Conium maculatum)
Pacific Water-parsley (Oenanthe sarmentosa)
Sweet Cicley (Osmorhiza chilensis)
Starflower (Trientalis arctica)
Dogbane (Apocynum androsaemifolium)
Periwinkle (Vinca major)
Grove Lover (Nemopila parviflora)
Phacelia (Phacelia nemoralis)
Blue Forget-me-not (Myosotis laxa)
Hedge Nettle (Stachys pubens)
American Speedwell (Veronica americana)
English Plantain (Plantago lanceolata)
Bellflower (Camanula scouleri)
Silver-green (Adenoculon bicolor)
Stinking Mayweed (Anthemis cotula)
Nodding Beggar-tick (Bidens cernua)
Bachelor's Button (Centaurea cyanus)
Chichory (Cichorium intybus)
Canada Thistle (Cirsium arvense)
Bull Thistle (Cirsium laneolatum)
Horseweed (Conyza canadensis)
False Dandelion (Hypochoeris radicata)
Prickly Lettuce (Lactuca serriola)
Twinberry (Lonicera involucrata)
Snowberry (Symphoricarpos albus)
Elderberyy, Red (Sambucus racemosa var. callicarpa)
Elderberyy Blue (Sambucus glauca)
Evergreen blackberry (Rubus leucodermia)
Blackcap (Rubus leucodermis)
Trailing Blackberry (Rubus ursinus)
Thimble-berry (Rubus parviflorus)
Hardhack (Spireae douglasii)
Pacific Willow (Salix lucinda ssp. lasiandra)
Scouler Willow (Salix scouleriana)
Sitka Willow (Salix sitchensis)
Pacific Dogwood (Cornus nuttallii)
Red Huckleberry (Vaccinium parviflorum)
Indentifications and scientific names used in this audit are taken from:
Plants of the Pacific Northwest Coast 1994. Ed. J. Pojar and A. MacKinnon. Lone Pine. Richmond, Washington.
Flora of the Pacfifc Northwest 1973. C.L. Hitchcock and A. Cronquist. University of Washington Press, Seattle.
A Field Guide Western Birds 1990. Roger T. Peterson. Houghton Mifflin, Boston.
Special Thanks is given to Una V. Davies for producing her accurate and comprehensive thesis, "Vascular Plants of the Reed College Campus" in 1938 (unpublished. Reed Library). I also thank Dr. Bert Brehm for his insightful and amusing assistance in identifying odd species, Dr. Keith Karoly for his assistance in keying out some of the tougher plants, Dr. Johnny Powell for his help in cataloging the birds of the Canyon, Dr. Bob Kaplan for with help the amphibian life, Dr. Tom Dunne for his information on the chemistry of the canyon, Rae Hafer for her help in indentifying some of the more common and semi-weedy (yet nearly immposible to key out) species, and Jimmy Huang for his help on the history of the canyon.