HomeMy WebLinkAboutPresettlement Vegetation/Lithia PRE-SETTLEMENT VEGETATION
of
LITHIA PARK
' by
Donn Todt
January 1994- Updated
CONTENTS
Page
Acknowledgements
Introduction
Riparian Vegetation ............................................. 1
Upland Vegetation .............................................. 3
B road leaf Trees
Oregon White Oak (Quercus garryana)
California Black Oak (Quercus kelloggii)
Madrone (Arbutus menziesii)
Coniferous Trees
Douglas-Fir (Pseudotsuga menziesii)
Ponderosa Pine (Pinus ponderosa)
Incense-Cedar (Calocedrus decurrens)
" Chaparral and Upland Shrubs .................................... 9
Forbs and Grasses
Summary .................................................... 12
References
APPENDICES
Appendix I ................................................... i
Checklist of Pre-settlement Native Vegetation Presently or Recently Occuring in
Lithia Park
Appendix II
Tolerance to Moisture Stress of Important Trees and Shrubs Native to Lithia Park
Appendix III
Tolerance to Shade of Important Trees and Shrubs Native to Lithia Park
Appendix IV
Fire Adaptations - Important Trees and Shrubs Native to Lithia Park
INTRODUCTION
Lithia Park is situated along Ashland Creek where the creek makes its transition from. the
foothills of the Siskiyou Mountains to the Bear Creek arm of the Rogue Valley. The
elevation is slightly above 2,000 feet. The slopes immediately above the creek are
relatively gentle to the west and steeper to the east. The soil is' derived from a bedrock of
"granite" and is generally coarse and fast draining. It has either formed in place or has
been deposited as alluvium along the creek's small floodplains. The land that comprises
Lithia Park was settled in the early 1850's (O'Harra, 1986) and the vegetation has been
greatly modified since that time, including the introduction of non-native plants. Today,
hundreds of non-native species flourish within the park. This paper seeks to identify the
major pre-settlement species - the native vegetation - and suggests how these species
might have interacted prior to the time of settlement.~
The pre-settlement time, considered in this paper, covers the period during which
indigenous people migh~ have used this area as a resource base. This timeframe includes
the late Pleistocene, the warmer interval following the Pleistocene (Xerothermic), and the
more recent and moderate, though variable, climatic regime.
Hopefully, Lithia Park lands will never become so developed that the original vegetation
is totally eclipsed. Each year, however, the landscape does changes, becoming further
removed from its pre-settlement state. Even ecological changes within the strictly native
components of the vegetation serve to obscure 'early patterns. Although we can never be
sure of the exact pi.ant associations existing during prehistoric times, this paper Will list
most of the main components of that vegetational mosaic. It will also rough in some of
the distributions and spacial ecological relationships.
'The area covered by this paper includes only about 100 acres. For the Ashland area as a whole,
see Hickman 1975. For some aspects of the Rogue Valley vegetation, see Detling 1961. For an analysis
of vegetational distribution in the Eastern Siskiyous, see Waring 1969.
ACKNOWLEDGEMENTS
I would especially like to thank Nan Hannon and Richard Olmo for encouraging me to
write this paper. Thanks to Frank/ang, Tom Atzet, Vern Crawford, Marty Main and
Wayne Rolle for reviewing the first and second drafts and making many helpful
suggestions. Thanks to Ann Benedict, Stella Gardiner and Patricia Fine for transforming
my roughly written paper into a clear and orderly form.
p. 1
!""
RIPARIAN VEGETATION
....
The native vegetation may conveniently be divided into riparian and upland species.2
The upland species may be found within the riparian zone as well, but the riparian
species are often restricted to only that particular zone. Riparian species require more
water than non-riparian species and often benefit from the greater water holding capacity
of a deeper alluvial soil. The primary trees comprising the riparian flora are white alder
(Alnus rhombifolia), bigleaf maple (Acer macrophyllum) and Oregon ash (Fraxinus
latifolia). Occasional black cottonwoods (Populus balsamifera ssp. trichocarpa)3 and
willows (Salix spp.) extend upstream into the park from riparian areas along the valley
floor. Smaller riparian trees include Douglas hawthorn (Crataegus douglasii), western
dogwood (Corn us nuttalii) and Pacific yew (Taxus brevifolia).
The primary environmental feature affecting riparian vegetation in Lithia Park is flooding.
At irregular intervals, Ashland Creek experiences major floods that create currents swift
enough to wash out riparian vegetation adjacent to the creek.4 The newly scoured
banks are the ideal habitat for the seedlings of white alder, bigleaf maple, and Oregon
ash. Of the three, white alders seem best adapted to take advantage of the scoured
banks. They grow rapidly in even aged stands, overtopping the competing vegetation.s
However, they do not reproduce well within their own shade, so the understory
eventually becomes dominated by more shade tolerant species. Within 80 to 100 years,
the alders become senescent and subject to oak-root fungus (Armellaria mellia). As the
older alders succumb, they are replaced by more shade tolerant. species such as bigleaf
maple, black oak, Douglas-fir, and incense-cedar. With time, however, the inevitable
flood occurs, vegetation is uprooted, and the cycle begins again.6Prior to settlement, the
riparian vegetation immediately along Ashland Creek in the vicinity of Lithia Park was
dominated by white alders [See photo. O'Harra 1981 :94]. The degree of dominance arid
age class representation for white alder is dependent upon the flood interval and
severity. During periods of time when floods were intense and recurred after relatively
short intervals, white alder dominated the vegetation [See Miller and Jm1nson 1973r~--~n
lThis physical division, though not absolute, may reflect, to some degree, a difference in
biogeographic origins. The creekside vegetation may have its origin in the "areta-tertiary geoflora"
while the upland species may be largely derived from the "madra-tertiary geoflora" (Raven and Axelrod
1978. See also Holstein 1984; Robichaux 1977).
3Although a large Fremont cottonwood (Populus fremontii) grows along the creek in Lithia Park it was
probably introduced.
.See photographs. The Daily Tidings; Jan. 17, 1974 and Jan. 19, 1984.
SMost of the young alders in the park date back to the 1974 flood. Many of the oldest alders, of which
there are very few left standing, are around 100 years, perhaps dating back to the flood of 1890.
6Judging from the vegetational evidence, stand replacement floods, under the current climatic regime, may
occur at least two times in a one-hundred year period.
"I'
p. 2
During times when flooding was less frequent, other species, such as bigleaf maple,
Douglas-fir and incense-cedar would predominate in the matrix. .
Within Lithia Park are a number of shrubs which, while not strictly riparian, are generally
found growing within the relatively mesic environment along and just above the creek.
These species are mostly deciduous and have higher water requirements than the more
drought adapted upland species. The most common of these creekside shrubs is
snowberry (Symphorocarpos albus). It is one of the first to leaf out in the spring and in
winter its white fruits are conspicuous on fine-textured, bare branches. Other important
shrubs growing along the creek include hazel, (Corylus corn uta), native blackberry
(Rubus vitifolius), mock orange (Philadelphus lewisii), ocean spray, (Holodiscus discolor),
two species of rose (Rosa californica and Rosa gymnocarpa), chokecherry (Prunus
virginiana), and, Oregon boxwood (Pachystima myrsinites).7 Most of these shrubs are
characterized by having a considerable degree of shade tolerance.
.;
Vines within the riparian zone include western clematis (Clematis ligusticifolia), and
greenbriar (Smilax californica).8 The native ferns along the stream course are swordfern
(Polystichum munitum) and licorice fern (Polypodium glycyrrhiza). Other notable, and
more strictly riparian, plants include horsetail (Equisetum arvense), scouring rush
(Equisetum hyemale), coltsfoot (Petasites frigid us) and rush (Juncus sp.).
lMany of these shrubs are found in more mesic non-riparian areas within the Ashland area as well. [See
O.E. Hickman 1975, map and p.7] Within the vicinity of Lithia Park, however, they are most abundant along
and adjacent to the stream channel area.
6possibly introduced.
.....'
p. 3
UPLAND VEGETATION
..:. ....
Above the mesic zone, on either side of the creek, is the drier upland zone. This area is
not subject to periodic flooding from Ashland Creek, but, in some cases, the vegetation
still benefits from sub-surface water moving downslope toward the riparian zone. This is
especially true on the western side of the creek where the slopes are more gentle and
the watershed is more extensive.
The vegetation of this zone is a complex assemblage of generally drought tolerant
species characteristic of the lower foothills of the Siskiyous. The predominant tree
species include California black oak (Quercus kelloggii), Oregon white oak (Quercus
garryana), madrone (Arbutus menziesii), ponderosa pine (Pinus ponderosa), incense-cedar
(Calocedrus decurrens) and Douglas-fir (Pseudotsuga menziesii). Common shrubs include
. whiteleaf manzanita (Arctostaphylos viscida), deer brush ceanothus (Ceanothus
integerrimus), snowberry (Symphoricarpos albus), Klamath plum (Prunus subcordata),
wild rose (Rosa gymnocarpa) and birch leaf mountain mahogany (Cercocarpus
montanus). Each of these species has different tolerances to drought and shading.
Prior to settlement, a major environmental influence affecting Jhis vegetation complex
was fire. Therefore, a discussion' of the more important species and their relationships to
drought, shading and fire is appropriate. The relationships between climate, shade
tolerance and fire frequency are very complex. An increase in fire frequency, for
example, could offset the effects of a decrease in temperature. The speculative
suggestions in this paper will, therefore, be very general and only preliminary
approxi mations.
Broadleaf Trees
III
Oregon white..Q<<k.(QuefEtlS ~p'an.a)
Oregon white oak is the most drought tolerant of the major tree species native to Lithia
Park [Franklin and Dyrness 1973:131]. It is currently uncommon within the lands~aped
portion of park. This may be partially due tothe presence of oak root fungus (Armellaria
mellia) associated with longterm summer irrigation practices. It is also quite likely that
white oak was uncommon along the creek during pre-settlement times as well. On the
drier west-facing slopes above the landscaped portions of the park, Oregon white oak
becomes much more common. Usually, in the immediate vicinity of Lithia Park, it mixes
with ponderosa pine, Douglas-fir and California black oak. In a few locations, generally
characterized by shallow, droughty soils which preclude other tree species, it occurs in
nearly pure stands that are more characteristic of the species [Thielnius 1968]. Most of
the Oregon white oaks on the hillside have a fairly small diameter (5 to 9 in. DBH) and
are probably younger than 125 years. Scattered across the west-facing slope, however,
are a few old savanna-form specimens having a significantly larger trunk diameter than
the rest of the oaks. These might possibly be remnants of a prehistoric stand and might
be indicative of the more open conditions maintained by fire in the past.
r -~.
p.4
Oregon white oak has several adaptations to fire. Thick bark protects the cambium,
especially of older trees, from light burning. These oaks readily sprout from the base after
the top portion is ki lied by a hot fire. There is ,a tendency for Oregon white oak to form
open stands under a regime of periodic fires. When fires are suppressed, the stands
become more closed. In the absence of fire, these closed stands are often overtopped by
more shade tolerant and faster growing species.9 Within the park, in the absence of fire,
Oregon white oak is being overtopped by Douglas-fir, California black oak and incense-
cedar.
Prehistorically, we might expect that in the immediate vicinity of Lithia Park, larger white
oaks would be comparatively more common under a regime of burning. Burns associated
with steep slopes and/or manzanita species, however, might have been hot enough to
severely damage oak stands. This is especially true on the ridge lines and on southwest-
facing slopes.
Under a drier climatic regime, white oak might have been more common above the
riparian zone along the creek since it is the most drought tolerant of the major tree
species in this area.10 With a wetter or cooler climate, white oak might have, decreased
in abundance in Lithia Park. The relative shade intolerance of white oaks would allow
other species better adapted to more moist, shady conditions to overtop and suppress
them. If ailburning regime prevailed, however, white oaks might maintain their
dominance on more gentle slopes as they did in the Willamette Valley. This would take
place even with significantly more precipitation and cooler temperatures than are
presently characteristic of the Rogue Valley.
California Black Oak (Quercus kelloggii)
A few old, savanna-form .California black oaks currently grace Lithia Park. These
originally developed without competition and, consequently, have straight main trunks
and relatively wide-spreading branches. They range in age from around 150 to 200
years. Today, these older trees are far outnumbered by younger, more closely grown
trees having smaller canopies. The younger trees main branches curve and reach for
exposure to more sunlight.
Black oak ranges from the riparian zone near the creek, up both the east and west
slopes, mingling with white oak, ponderosa pine, madrone, Douglas-fir and incense-
cedar. It is more characteristically associated with coniferous forest species than is white
oak and is less apt to be found in pure or nearly pure stands. The black oaks, in this
landscape, become larger than the white oaks and so are capable of overtopping them
on deeper soils and cooler sites, such as occur in the lower portion of the park.
9For a'more complete discussion of Quercus garryana forests in the Willamette Valley see Thilenius, 1968.
lOpresently, in the more xeric sections of the Rogue Valley, white oak tends to be restricted to the banks of
small stream courses.
T"""
p. 5
Black oak seems to be somewhat more shade tolerant than white oak. Saplings and small
t'Pees may often be seen in the shade of ponderosa pines and other species. If the .
overstory species die, the oaks can then appropriate their locations. Black oaks appear to
be more competitive than the white oaks under a mixed forest situation. Black oaks are,
however, susceptible to severe damage by even low intensity fires [Plum 1979:211 l.
During warmer, drier periods, and/or periods of time having a high fire frequency, black
oak may have become less common than the more drought and fire resistant white oak
except in areas adjacent to the riparian zone."
Pacific madrone (Arbutus menziesij)
Pacific madrone ranges throughout Lithia Park wherever the soil is not too heavily
irrigated. Frequent summer irrigation makes the trees susceptible to root rot. Madrone is
especially common along the creek, upstream from Pioneer Street, where it forms almost
pure stands in several locations. The trees range up the hillside on both sides of the
creek. On the slopes, they usually occur in mixed stands with other species.
With regard to moisture stress, Pacific madrone is less tolerant than the oaks and seems
to be more tolerant than Douglas-fir. Although it is evergreen, the previous year's leaves
are shed in the early summer to help conserve moisture. Madrone has a moderate
tolerance to shade and co-exists with other taller species. Like the oaks, most 'of the
madrones in the park have narrow crowns due to close spacing and competition for
light. A few large, open-grown specimens exist on the west-facing hillside above the
landscaped portion of the park.
The Pacific madrone, like several other plants discussed later in this paper, tends to
create conditions that favor fire. Its peeling bark and litter of small branches result in a
rapid accumulation of fine and easily ignitable fuels. Its presence is usually indicative of
prior fire disturbance [Atzet and Wheeler 1982; Appendix B]. Many stump-sprouted
madrones may be observed on the hillsides west of Ashland Creek where a fire burned
in 1959 [O'Harra 1986: 158].
In the past, during periods of more xeric climate and/or high fire frequency, the
abundance of madrone may have been reduced on the drier sites relative to manzanita
and other chaparral species even better adapted to drought and frequent fires. During
wetter and cooler phases, they may have been overtopped by larger coniferous species,
becoming more common with disturbance by fire.12
l11n 1988, after three years of below average precipitation, some older California black oaks died on the
west-facing hillside above the developed section of the park. Although leaf scorch occurs on white oaks, no
mortality has yet been noted.
12The seed 'of madrone is often spread by birds. In the winter of 1986-87, there was a heavy concentration
of robins and thrushes in the park. They were probably feeding in madrones west of the park during the day
and roosting in the park at night. In the spring of 1987, we noticed that madrones were sprouting nearly as
thickly as grass below the roosting areas.
r
p. 6
Coniferous Trees
.
Douglas-fir (Pseudotsuga menziesii)
Douglas-fir is, today, the most common conifer species in Lithia Park. It ranges from
above the stream course up the east and west hillsides. Some of the largest specimens
are found adjacent to the creek where air and soil moisture are adequate for rapid
growth. Other large specimens grow adjacent to lawn areas. Many of the Douglas-firs in
the lower section of the park were brought in from further up the canyon and planted
about 1915 [Scripter 1965:6]. It is likely that the lower riparian and near-riparian sections
of the park supported some Douglas-fir in prehistoric times as well. On the west-facing
hillside, above the landscaped section of Lithia Park, Douglas-fir is near the limits of its
environmental tolerance. Steep slopes, granitic soils, hot exposures, periodic scant
rainfall and competition all combine to make conditions difficult for the trees.13
During climatically favorable periods, Douglas-firs form thick stands, only to be stressed
later by drought and/or competition with each other. These stressed stands are then
targets for the Douglas-fir bark beetle (Pseudohylesinus nebulosus) and the flat-headed
Douglas-fir borer {Melanophilla drummondi).14
Douglas-fir has a moderate tolerance to shade [Franklin & Dyrness 1973:130-131]. It can
often regenerate in the shade of such associates as California black oak, Oregon white
oak, or ponderosa pine. Were it not for moisture stress, Douglas fir would probably be
far more common on the hillside above the park than it is today.
In terms of fire ecology, young Douglas-firs are quite susceptible to burning. Older trees
develop a thick corky bark that helps protect the cambium from injury. In addition, they
self-prune their lower limbs which makes fires less likely to crown and kill whole trees.
Self-pruning, however, adds to the fine litter accumulation on the forest floor. Thus, the
Douglas-fir "tends to produce conditions that favor fire wherever it occurs" [Atzet and
Wheeler 1982]. The ash and exposed mineral soil left after a fire is a preferred seedbed
for the species [Atzet and Wheeler 1982: Appendix B].
Prehistorically, Douglas-fir would have been a more important species during slightly
cooler, wetter climatic r~gim~s. During drier periods, such as the xerothermic, it seems
likely that Douglas-fir would have been eliminated from Lithia Park except for, perhaps,
IlBetween 1987 and 1992, 90% of the Douglas fir stand on the west- facing hillside was eliminated by
borer beetles. Some 6 to l.4-inch DBH individuals were found to be as much as 100+ years old. Beetle killed
trees, felled in 1989, averaged lS-inches in diameter with 83 growth rings.
14prehistoricaly, the primary influence of bark beetles and borers may have been to eliminate trees
weakened by fire or competition, Perhaps, during periods of greater fire frequency, Douglas-fir stands would
have been thinned out enough to lessen competition between closely spaced trees which consequently would
have lessened their susceptibility to massive beetle or borer attack. .
~
p.7.
immediately adjacent to the creek where higher humidity, deeper soil and an adequate
water supply might have permitted its survival.
,. '"
Ponderosa Pine (Pinus ponderosa)
Scattered along Ashland Creek, as it flows through Lithia Park, are some magnificent
specimens of ponderosa pine. Many are older than 80 years, which is approximately the
age at which they begin to show cinnamon-colored bark. Most of these older trees date
prior to the establishment of the park and some date to well before the time the region
was first settled.15 Their presence is indicative of more open conditions in the past. The
ponderosa pine is quite shade intolerant, consequently few young trees are presently
found in the shady lower creekside section of the park. In the absence of fire, or other.
major disturbance, the ponderosa pines will most likely be replaced by more shade
tolerant species.
On the west-facing hillside, above the developed section of the park, are a few trees of a
size comparable to those down below, and many smaller trees as well. Because a good
number of these trees are located in stressful locations, they are often older than their
size would normally indicate. On these dry exposures, ponderosa pin~ co-exists with
black and white oak, while in more mesic locations it is interspersed with, and
sometimes replaced by, Douglas-fir. Prior to the early 1990's, on the west-facing hillside,
Douglas-firs outnumbered ponderosa pines. However, due to the yearly attrition of
Douglas-firs from bark beetle and flat-headed borer attack, and the lessened incidence of
insect problems with ponderosa pine, the balance seems to be shifting in favor of
pine.16 Although there are both young and older pines in the stand, it is mostly even-
aged, probably dating back to the late 1800's.
Ponderosa pines are fire-adapted in several important respects. On older trees, a thitk
bark often prevents fire from severely burning the cambium. When burned, ponderosa
pines have a well-developed ability to compartmentalize wounds. Younger trees are also
better adapted to withstand fire than many common associates [Frallklin and Dyrness
1973: 180]. Ponderosa pines tend to self-prune lower limbs, thus making it less likely that
fires would spread into the crowns of the trees. Pine also prefers a mineral soil for good
seed germination [Atzet and Wheeler 1982: Appendix B] and fire is the agent that
traditionally exposes these soils.
Ponderosa pine has probably been a common component of the vegetation since at least
the beginning of the xerothermic. As drought increased during the xerothermic,
ponderosa pine likely became more abundant. During the wetter, cooler periods,
species better adapted to shade and moisture, such as Douglas-fir and white fir (Abies
concolor), may have been relatively more common in the matrix. Judging from early
150ne beetle-kill Ponderosa pine felled in 1993 had at least 200 rings.
'6prior to 1988-89 there was little or no recent incidence of beetle attack on ponderosa pine in Lithia Park.
Attrition began that year and has continued through the drought years of the early 1990's eliminating about half
of the stand, especially those growing in close proximity to one another.
,.-
p. 8
.....~
' .-:..
_._'_.'~'.c....
jA ._._.,
-=--.- . -;. . ...:
photographs of Lithia Park, ponderosa pine was the predominant co~iferous species
during the late pre-settlement period and early settlement times.'?
Incense-Cedar (Ca/ocedrus decurrens)
Largeincense-cedars are relatively abundant throughout the lower creekside section of
Lithia Park. On the hillside, there are very few older specimens, but, where a seed
source is nearby, they became, until the late 1980's, increasingly common in the
understory. Incense cedar seeds are able to germinate in a duff layer and they are quite
shade tolerant (Atzet and Wheeler 1982: Appendix B). Although the recent absence of
fire from the hillside has created conditions favorable for the reproduction of this species,
periodic drought seems to have served as a population check.'8
Perhaps a greater fire frequency in the past has kept incense- cedar from becoming a
more important species in what is now Lithia Park. Although older incense-cedars are
quite fire adapted, their initial slow growth rate puts them at a disadvantage where the
fire frequency is short.'9 Prehistorically, incense-cedar may have been a more important
component of the vegetation when fires were uncommon. During times when the fire
frequency was high, incense-cedar would tend to be restricted to areas least likely to
burn, i.e., along the creek.
17Photographs are available for viewing at the Ashland Parks and Recreation Department office and at the
Southern Oregon Historical Society Museum.
180ne of the few larger DBH trees on the hillside recently died (1989). It had a trunk diameter of 20-inches
and was about 115 years old with probable fire scar rings. During the drought years of the late 1980's and early
1990's, many smaller diameter incense cedar died on the west-facing hillside.
190n the dry, west-facing slope above the developed section of Lithia Park, three-foot high trees are often
more than 10-years old.
.......
p. 9
Chaparral and Upland Shrub Species
The upland shrub species include both evergreen and deciduous forms. Poison oak (Rhus
diversiloba) is perhaps the most common species on the hillside, growing as an
understory beneath oak, pine, and Douglas fir. Mountain mahogany (Cercocarpus
montanus) is especially abundant on the north-facing slope above .the plaza and below
Glenview Drive, north of the city cinder storage yard. Klamath plum (Prunus subcordata)
occurs in scattered stands on the west-facing hillside.20
Scattered along the hillside, and especially abundant in the draws and toward the top of
the slope, are stands of whiteleaf manzanita (Arctostaphylos viscida). Many of these
stands are old and decadent and are being overtopped and replaced by various tree
species. These stands probably date to 80 or 100 years ago when the last major fires
burned on the hillside. Although this species of manzanita doesn't stump sprout [Atzet
and Wheeler 1982; 10], it has many fire-adapted characteristics. In fact, the species might
be said to create conditions that favor fire and the shrubs consequent decimation and
rejuvenation. It has an abundance of fine twigs which, when they are shaded, die and
become dry, hot burning fuels. When a manzanita is burned, it releases gasses which
make the fire burn even hotter. Its seeds readily and quickly germinate in the soil left
after a burn. Even if manzanita is overtopped and killed by later successional species, the
seeds lie dormant in the soil, waiting for the next fire to create conditions which favor its
perpetuation.
Prehistorically, because of frequent burning, whiteleaf manzanita stands were younger
and more abundant. Stands were probably frequently renewed by fire before they were
overtopped and shaded out by competing species. During the Xerothermic period,
because of its drought tolerance and adaptation to fire and shallow soils, whiteleaf
manzanita was possibly a dominant species on the hillside. After this period, its degree
of dominance would have been related to the frequency and intensity of fires. Prior to
the Xerothermic, other species, better adapted to cooler, moister conditions, would likely
have existed where manzanita is found today.
Oeerbrush (Ceanothus integerrimus) grows as scattered individuals on the west-facing
hillsides above the riparian zone. It is semi-deciduous and seems to have more tolerance
of shade than manzanita. It is an important browse plant for deer. Oeerbrush stump
sprouts readily after being burned [Atzet and Wheeler 1982: Appendix B]; consequently,
an increased fire frequency would likely result in more deer browse available from this
speCIes.
10, have noticed very little fruit production from these stands. They seem to be .subject to a fungus
(Monolinia sp.) every spring. This fungus develops most readily in mild,.moist conditions; perhaps thus
inhibiting the fruit production of Klamath plums. That these stands are not reproducing by seed may indicate
that they are remnants from a more favorable climatic period. Alternatively, the lack of fruit may be a result of
the introduction of this fungus into the region.
'"r"'
p. 10
Another ceanothus, buckbrush or wedgeleaf ceanothus (Ceanothus cuneatus), is rarely
found on the west-facing hillside above the developed portion of Lithia Park. It is,
however, -more common- in the foothills west of the park. Detling [1961 :84] notes that it
is the most drought tolerant of the common shrubs in this area. It is an important
component of the northern California chaparral association. Detling [19611 believes that
during the Xerothermic, this species, and some of its common associates, spread
northward from California into Oregon. Its adaptatio~s to fire are comparable to those of
white/eaf manzanita. .
Hairy honeysuckle (lonicera hispidula), a vine, is common in the understory, especially
under conifers on the hillside portion of the park. It is most prevalent, and forms a nearly
continuous ground cover, on the steep hillside just above the southern boundary of
Lithia Park.21 Its presence is usually indicative of a hot, dry site [Atzet & Wheeler 1982:
Appendix B].
21Most of the Douglas-firs that once served as an overstory for this species were killed by flat-head borer
during the 1988-89 season.
-,-
p. 11
FORBS and GRASSES
A wide variety of herbaceous species are found on the hillsides of Lithia Park. These are
especially prominent in the spring and seem to be more common under deciduous oaks
and scattered ponderosa pines than under Douglas-firs. The most noticeable include
balsam root (Balsamorhiza deltoidea), Hounds tongue (Cynoglossum grande),
Henderson's fawn lily (Erythronium hendersonii), shooting star (Dodecatheon
hendersonii), Menzies' larkspur (Delphinium menziesii), and scarlet fritillary (Fritillaria
recurva). All are presumed to have been present during pre-settlement times. Many of the
native wildflowers are currently being encroached upon and suppressed and will
eventually be excluded by the introduction of Scotch Broom (Cytisus scoparius),
periwinkle (Vinca major) and English Ivy (Hedera helix).
Most of the grasses in the lower part of Lithia Park have been replaced by ornamental
turf species. On the hillside, prior to the late 1980's, grasses were suppressed by a nearly
continuous cover of trees and shrubs. The increase in light intensity, afforded by the
decimation of the Douglas fir stands, has recently resulted in an increase in grass
coverage. However, many of these grasses are the non-native, annual species which have
displaced the native perennial bunch grasses. Hickman [1975] lists Idaho fescue (Festuca
idahoensis), western fescue (Festuca occidental is), dunegrass (Koeleria cristata), pine
bluegrass (Poa scabrella) and California brome (Bromus carinatus) as occurring in pre-
settlement associations in the vicinity of Lithia Park. California Oatgrass (Oanthonia
California) may well have existed in the vicinity of Lithia Park as well. Prehistorically,
many forbs, grasses, and especially geophytes would have been favored by an increased
fire frequency resulting in reduced coverage by trees and shrubs Uohannessen et al.
1971].
,...'
p. 12
SUMMARY
Although we can never be sure of the exact plant associations that existed during
prehistoric times, we can, nevertheless, make an analysis based upon the ecological
requirements and preferences of species present in the area today. The following
speculative suggestions should be treated as first approximations which might be refined
in light of additional information.
Vegetation at the Time of Settlement
At the time of settlement, in the 1850's, the native vegetation immediately adjacent to
Ashland Creek in Lithia Park likely included many of the same species that grow there
today. White alder predominated along flood scoured banks. Bigleaf maple and Oregon
ash also grew along the creek edge as well as on moist less disturbed sites. The existence
of large ponderosa pines near the creek indicates that the canopy during late pre-
settlement times was much more open than it is today.
On the hillside, ponderosa pine was the most abundant coniferous species, with
Douglas-fir and incense-cedar probably existi.ng as minor components of the oV(~rstory
vegetation. Black oak was more common on the deeper soils close to the creek, while
white oak predominated on the more shallow soils of the hillside. Manzanita was mOI_
common and in more youthful stands than it is today. Frequent fires gave fire-adapted
species an advantage over non-fire-adapted species, though the mix would depend on
fire frequency.22 The hillsides were generally more open with grasslands more
prominent than at present. White oaks may have existed in a savanna situation along
some of the slope.
Pre-settlement Vegetation
(about 4,500 b.p. to the 1850'5)
.
The climate for, the previous 4,500 years was similar to that at settlement, though it was
variable, with both long and short term fluctuation between warmer to cooler and wetter
to drier periods. Fluctuations during this period of time were probably not 50 great as to
exclude any of the more common species, though species abundance did vary according
to the prevailing regime.
As changes took place, the existing species distributed seeds covering the full range of
environmental tolerance. The weather extremes for each given year would have selected
22Historical and archaeological evidence of a pre-historic Shasta Indian village in what is now the front
section of Lithia Park would indicate a higher fire frequency for the area than would have been caused by
lightning alone (see Lewis, 1973).
......'
p.13
those individuals that would survive, resulting in a dynamic interaction between species
abundance and c1imate.23 Since Lithia Park is near the margin of drought tolerance for
trees such as Douglas-fir and incense-cedar, even relatively moderate climatic
fluctuations would likely have had a pronounced effect on the mix of species. The
vegetation was probably consistantly in some state of flux.
During this period of timet aboriginal hunters and gatherers occupied the area to a
greater or lesser extent. Their presence, populations densities, and the precise location of
their villages would have influenced the vegetational mosaic by affecting the fire
frequency and intensity (see Lewis, 1973). When population densities were low, or
villages were far removed from the area, fire frequency would have approached the
normal, erratic background of lightning caused fires. When villages were nearby, or
population densities were high in the area, more frequent and lower intensity fires would
have selected for species adapted to that regime (see Appendix IV).
Vegetation in the Xerothermic Period
(about 8/000 ? to 4,500 b.p.)
As we look back into the past, the first major break in the continuity of the pre-
settlement plant distribution patterns occurs during the Xerothermic, a major warm and
dry period which began not long after the end of the Pleistocene.
During this interval of time, the riparian zone probably contracted to a very narrow
margin along the creek. If flood frequency and intensity were less than it is today,
species other than white alder may well have predominated along this margin.
Pdnderosa pine may have been a common species near the creek, existing there, as it
does today, along creeks running through otherwise i!lhospit(!ble terrain in eastern
Oregon. Even Oregon white oak may have encroached upon the margins of the riparian
zone.
._.~.-. During the Xerothermic, less drought tolerant species, s'uch as incense-cedar, Douglas-fir,
.. ~- western dogwood and hazel, were probably eliminated from the mix. Drought and fire-
adapted species, such as buckbrush and manzanita, were likely more common, as they
are today in the northern California chaparral associations. Additional woody species, not
present in the later pre-settlement time, might have included yerba santa (Eriodictyon
californicum) and three-leaf sumac (Rhus trilobata). The whole vicinity was much more
open and grasses were a much more important component of the vegetation than they
are today.
231 am indebted to Tom Atzet for this analysis of the interaction between climate and vegetation.
r
.....
p. 14
.
Vegetation in the Late Pleistocene
It is only a relatively short step in time from the 'xerothermic interval to the late
Pleistocene (ending about 10,000 b.p.); however, the change in the landscape of what is
now Lithia Park was probably extraordinary. Drought and fire-adapted chaparral species,
such a whiteleaf manzanita and buckbrush, would probably not yet have become
common in this region (Detling, 1961). Species adapted to more moist conditions,
shade, and cold air drainage probably predominated in the mix (see Appendix II & III).
Those species characteristic of the riparian zone, such as western dogwood and bigleaf
maple, probably had ranges extending wefl beyond where they are found today in Lithia
Park. Douglas-fir and incense-cedar were likely to have been common components of the
mix. Sugar pine, white fir, salal (Gaultheria shallon'" vine maple (Acer circinatum),
western rhododendron (Rhododendron macrophyllum) and Engelmann spruce (Picea
engelmanii) may well have been common in what is now Lithia Park. Large browsing or
grazing mammals such as mammoths, horses, camels and bison may have influenced the
distribution and abundance of some species. When these large herbivores became
extinct, there was probably a corresponding response in the vegetation.
The landscape that comprises what is now Lithia Park has seen many changes since the
late Pleistocene. Species appeared, disappeared, or changed abundance in response to
climatic changes and the proximity and density of aboriginal populations. The greatest
changes in the landscape, however, began to take place in the 1850's when the region
was settled. Logging, grazing, farming, mining, the intentional and unintentional
introductions of exotic plants, irrigation, and the elimination of fire from the ecosystem
have all had an effect on native vegetation. All have helped to shape the landscape that
exists today.
.
..,....'
p. 15
REFERENCES
Atzet, Thomas and D. L. Wheeler
1982. Historical and Ecological Perspectives on Fire Activity in the Klamath
Geological Province of the Rogue River and Siskiyou National Forests.
USDA - For. Serv., PNW Region, Portland.
Barbour, Michael G. and J. Major
1977-88. Terrestrial Vegetation of California. Calif. Native Plant Society, pub. no. 9.
Davis, Calif.
Crawford, Vern .
1984. Lithia Park Woodland Trail: Guide to Trees and Shrubs. Ashland Parks and
Recreation Department, Ashland, Oregon.
Detl i ng, LeRoy E.
1961. The Chaparral Formation of Southwestern Oregon, with considerations of its
postglacial history. Ecology 42: 348-357.
Franklin, Jerry F. and C. T. Dyrness
1973. Natural Vegetation of Oregon and Washington. USDA For. Servo Gen. Tech.
Rept. PNW-8. US Govt. Print. Off, Washington.
Hickman, Eugene O.
1975. Potential Native (Original) Vegetation of the Ashland, Oregon Area. Soil
Conservation Service, USDA. Map and Report.
Holstein, Glen
1984. California Riparian Forests: Deciduous Islands in an Evergreen Sea. In
California Riparian Systems, pp. 2-22, U.c., Berkeley.
Johannessen, Carl L.
1971. The Vegetation of the Willamette Valley. Ann. Assoc. Am. Geog. 61 (2):286-
302.
Lewis, H. T.
1973.
Patterns of Indian Burning in California; Ecology and Ethnohistory. Ballena.
Press, Ramona, Cal if.
Miller, T. B.
1977.
Ecology of Riparian Communities dominated by White Alder in Western
Idaho. In Proceedings on the Symposium on Terrestrial and Aquatic
Ecological Studies. R.D. Andres et al. (Eds) E.W.S.C. Press, Cheney, Wash.
(Avail. SOSC Lib.)
...-
p. 16
References
con't.
O'Harra, Marjorie
1986. lithia Park. Ashland Parks and Recreation Department, Ashland, Oregon.
O'Harra, Marjorie
1981. Ashland: The First 130 Years. Southern Oregon Historical Society,
Jacksonville, Oregon.
Plum, Tim R.
1979. Response of Oaks to Fire. Proceedings of the Symposium on the Ecology,
Management, and Utilization of California Oaks. Claremont, California. U.S.
For. Serv., Gen. Tech. Rpt. PSW-44.
Raven, Peter H. and D. I. Axelrod
1978. Origin and Relationships of the California Flora.
U.c. Press, Berkeley.
Robichaux, Robert
1977. Geologic History of the Riparian Forests of California. In Riparian Forests ir
California: Their Ecology and Conservation. Sands, A. (Ed.) U.c. Press,
Berkeley, 1980. pp. 21-35.
Sands, Anne (Ed.)
1980. Riparian Forests in California: Their Ecology and Conservation. U.c. Press,
Berkeley.
Scriptor, Eldon
The Lithia Park Story. Avail. Ashland Library, Ashland, Oregon.
Thilenius, John F.
1968. The Quercus garryana ,Forests of the Willamette Valley, Oregon. Ecology
49: 1124-1133.
Waring, R. H.
1969. Forest Plants of the Eastern Siskiyous: Their Environmental and Vegetational
Distribution. Northwest Sci. 43: 1-17.
Warner, Richard E. and K.M. Hendrix (Eds.)
1984. California Riparian Systems (Ecology, Conservation, and Productive
Management) U.c. Press, Berkeley 1984.
r
Appendix I
CH ECKLlST
of
PRE-SETTLEMENT NATIVE VEGETATION EXISTING in UTHIA PARK TODAY
TREES
COMMON UNCOMMON RARE
Acer macrophyllum
Alnus rhombifolia
Amelanchier alnifolia
Arbutus menziesii
Crataegus douglasii
Cornus nuttallii
Fraxinus latifolia
Calocedrus decurrens
Pinus ponderosa
Pinuslambertiana'
Populus balsamifera
ssp. trichocarpa
Quercus garryana
Quercus kelloggii
Taxus brevifolia
SHRUBS AND VINES
Big Leaf Maple . . . X
Wh ite Alder . . . . . X
Pacific . . . . . . . . . . . . . . . . . . . X
Serviceberry
Madrone ....... X
Black Hawthorn ............ X
Pacific Dogwood . X
Oregon Ash ..... X
Incense-Cedar . . . . X
Ponderosa Pine. . . X
Sugar Pine ..................... . . . . X
B lack Cottonwood . . . . . . . . . . . X .
Oregon White Oak X
California
B lack Oak ..... X
Western Yew .............. X
Arctostaphylos viscida
Berberis piperiana
Berberis nervosa
Castanopsis chrysophylla
Ceanotbus cuneatus
Ceanothus intergerrimus
Cercocarpus montanus
Clematis ligusticifolia
Whiteleaf . . . . . . . X
Manzan ita
Pipers
Oregon-grape . . . X
Dwarf
Oregon..:grape . . . . . . . . . . . . . X
Shrub Chinquapin. . . . . . . . . . . . . . . . . . . . X
Buckbrush ......................... X
Deerbrush ...... X
Birch Leaf ...... X
Mt. Mahogany
Western Clematis ........... X
'One individual was growing with native species on the west- facing hillside well above the developed
portion of the park. It is presumed not to have been planted. This tree died during the 1988-89 season.
.,....
Appendix I
SHRUBS AND VINES
COMMON UNCOMMON RARE
Cornus glabrata
Coryl us corn uta
Garrya fremontii
Gaultheria shallon
Holodiscus discolor
Lonicera ciliosa
Honeysuckle
Lonicera hispidula
Pachistima myrsinites
Philadelphus lewisii
Phoradendron flavescens
var. villosum
Physocarpus capitatus
Prunus demissa
Prunus subcordata
Rhamnus purshiana
Rhus diversiloba
Ribes divaricatum
Gooseberry
Ribes sanguineum
Current
Rosa californica
Wild Rose
Rosa gymnocarpa
Rubus parviflorus
Rubus vitifolius
Salix (Iasiolepsis?)
Sambucus glauca
Smilax californica
Symphoricarpos albus '
Smooth Dogwood .. . . . . . . . . . . . . . . . . . " X
Hazel ......... X
Fremont Silktassle . . . . . . . . . . . . . . . . . . .. X
Salal ............................. X
Ocean-spray . . . .. X
Orange Flower
........................ X
Hairy Honeysuckle X
Oregon Boxwood X
Mock Orange . . .. X
Oak Mistletoe. . .. X
Ninebark ................. X
Chokecherry . . . .. X
Klamath Plum . . . . . . . . . . . . .. X
Cascara .................. X
Poison Oak ..... X
Straggly
........................ X
Red Flowering
............. ... ... .. . .. X
California
.............. X
Wood Rose ..... X
Thimbleberry .... X
Blackcap ....... X
Willow........................... X
Blue Elderberry. . . . . . . . . . . . . . . . . . . . '.' X
Greenbriar . . . . .. X
Snowberry ...... X
1/
..,....
FORBS2
Achillea lanulosa
Artemissia douglasiana
Balsamorhiza deltoidea
Boschiniakia strobilacea
Calochortus tolmiei
Calypso bulbosa
Campanula scouleri
Castilleja sp.
'Collinsia sp.
Crocidium multicaule
Cynoglossum grande
Delphinium menziesii
Dentaria sp.
Dichelostemma pulchellum
Disporum tachyandrum
Dodecatheon hendersonii
Epilobium angustifolium
Eriophyllum lanatum
Erythronium hendersonii
Equisetum arvense
Equisetum hyemale
Escholtzia cal iforn ica
Fragaria californica
Fritillaria lanceolata
Fritillaria recurva
Calium nuttallii
Gilia capitata
Hieracium albiflorum
Iris chrysophylla
Lithophragma affine
Lomatium californicum
Lomatium dissectum
Montia sp.
Petasites frigidus
Phacelia sp.
Pityrograma triangularis
Polypodium glycyrrhiza
Polystichum munitum
Ranunculus occidental is
Saxifraga sp.
Senecio integerrimus
Yarrow
Sage
Balsam Root
Ground Cone
Pussy Ears
Calypso Orchid (rare)
Scoulers Bellflower
Indian Paintbrush
Collinsia
Spring Gold
Pacific Hound's Tongue
Menzies' Larkspur
T oothwort
Blue Dicks
Fairybells
Henderson Shootingstar
Tall Fireweed (uncommon)
Oregon Sunshine
Henderson Fawn Lilly
Horsetai I
Scouring Rush
California Poppy
Strawberry
Mission Bells
Scarlet Fritillary (uncommon)
Climbing Bedstraw
Blue Cilia
White Hawkweed
Slendertube Iris.
Woodland Star
California Lomatium
Fern-Leaf Lomatium
Miners lettuce
Coltsfoot
Phacelia
Goldbacked Fern (rare)
Licorice Fern
Sword Fern
Buttercup
Saxifrage
Tower Butterweed
2 This is not a complete list, however, it does include most of the obvious and ethnobotanically important
species.
III
..,.... --
Sisyrinchium douglasii
Smilacina racemosa
Grass-Widows Jrare)
Western Larger False
Solomon's Seal
Starry False
Solomon's Seal
Golden rod
Snow Queen
Hendersons Stars
Native vetch
Smilacina stellata
Sol idago canadensis
Synthyris reniformis
Triteleia hendersonii
Vi cia sp.
GRASSES AND GRASSLIKE PLANTS3
Appendix I
,~,r- --
Bromus carinatus
Festuca idahoensis
Festuca occidental is
Juncus sp.
Koeleria cristata
Poa scabrella
California Brome
Idaho Fescue
Western Fescue
Rush
Dunegrass
Pine Bluegrass
.It
. !,~-...'"I'.. .,
JAdapted from Hickman 1975, Appendix III.
..,...'
IV
Append ix II
TOLERANCE TO MOISTURE STRESS
Species
Ceanothus cuneatus
Rhus diversiloba
Arctostaphylos viscida
Lonicera hispidula
Quercus garryana
Cercocarpus betuloides
Quercus kelloggii
Pinus ponderosa
Arbutus menziesii
Rosa gymnocarpa
Calocedrus decurrens
Pseudotsuga menziesii
Rosa californica
Berberis piperiana
Holodiscus discolor
Pinus lambertiana
Philadelphus lewisii
Acer macrophyll u m
Corylus corn uta
Cornus nuttallii
Fraxinus latifolia
Alnus rhombifolia
of Important Trees and Shrubs
Native to lithia Park4
Common Name
Buckbrush
Poison Oak
Whiteleaf Manzanita
Hairy Honeysuckle
Oregon Wh ite Oak
Birchleaf Mt. Mahogany
Calif. Black Oak
Ponderosa Pine
Madrone
Wood Rose
Incense-Cedar
Douglas-Fir
Wi Id Rose
Pipers Oregon-grape
Ocean-spray
Sugar Pine
Mock Orange.
Bigleaf Maple
Hazel
Western Dogwood
Oregon Ash
White Alder
4Adapted from Franklin and Dyrness 1973:130.
T'"' .. -
Tolerance
High
Low
v
Species
Lonicera hispidula
,Berberis piperiana
Rhus diversiloba
Symphoricarpos albus
Cornus nuttallii
Acer macrophyllum
Calocedrus decurrens
Pseudotsuga menziesii
Pinus lambertiana
Arbutus menziesii
Quercus kelloggii
Pinus ponderosa
Quercus garryana
Arctostaphylos viscida
Ceanothus cuneatus
Fraxinus latifolia
Alnus rhombifolia
Appendix III
TOLERANCE TO SHADE
of Important Trees and Shrubs
Native to Lithia Parks
Common Name
Hairy Honeysuckle
Pipers Oregon Grape
Poison Oak
Snowberry
Western Dogwood
Bigleaf Maple
Incense Cedar
Douglas Fir
Sugar Pine
Madrone
Calif. Black Oak
Ponderosa Pine
Oregon White Oak
Whiteleaf Manzanita
Buckbrush
Oregon Ash
White Alder
5 Adapted from Franklin and Dyrness 1973:pp. 130-131.
..,-'
Tolerance
High
Low
VI
Appendix IV
FIRE ADAPTATIONS
of Important Trees and Shrubs
Native to Lithfa Park6
Resistant Produces
Stump to Light Abundant
Species SproutsBurns Fuels
Acer macrophyllum x
Arbutus menziesii x x
Arctostaphylos viscida x
Berberis piperiana x
Ceanothus cuneatus x
Cercocarpus montanus x x
Corylus cornuta x
Fraxinus latifolia x
Calocedrus decurrens x
Lonicera hispidula x
Pinus ponderosa x x
Pseudotsuga menziesii x x
Quercus garryana x x
Quercus kelloggii x
Rhus diversiloba x
Rosa gvmnocarpa x
6 Adapted from Atzet and Wheeler 1982: Appendix B.
VII
.....^
-A
..,......