Botrychium hesperium in the Wallowa Mountains of Oregon

2 Pages·2002·1.2 MB·English

by  Peter F Zika

American Fern Journal 92(3):239-246 (2002}
Shorter Notes
—
Botrychium hesperium in the Wallowa Mountains of Oregon. The
Wallowa Mountains of northeastern Oregon boast the greatest fern diversity
We
in the reported 47 taxa in the range (Zika & Alverson, Amer. Fern
state.
A
which number
61-64. included 14 taxa of Botrychium. of
86: 1996}, ele-
J,
ments from Rocky Mountains found Wallowa County, which
the are in to
we can now include Botrychium hesperium (Maxon & R. T. Clausen) W.H.
Wagner & an addition the Oregon (Wagner & Wagner, Ophio-
Lellinger, to flora
glossaceae in Flora North America, Vol. Oxford Univ. Press, 1993).
of 2,
Botrychium hesperium Wallowa Mountains narrow
restricted in the to a
is
band between 1535-1660
elevational in the Lostine River drainage, meters,
where steep canyon walls shade the valley floor from direct sunlight early
meadows
and late in the day. It is found in mesic or forest edges, in full sun
or partial shade, at all aspects, but only on gentle slopes or flats on the valley
The
floor. has yet to be located on steep slopes at higher elevations. forests
It
are primarily Pinus contorta Dougl. ex Loud., with low wet areas dominated
by Picea engelmannii Parry ex Engelm. Associated herbs include: Achillea
millefolium Agoseris aurontiaca (Hook.) Greene, Antennario rosea Greene,
L.,
Calamagrostis rubescens Buckl., Carex concinnoides Mack., C. geyeri Boott,
hoodii Boott, Elymus glaucus Buckl., Erigeron compositus Pursh, Festuca
C.
Duchesne, Gentiana amarella
occidentalis Hook., Fragaria virginiana L.,
Sedum
Hieracium Hook., Linnaea borealis stenopetalum Pursh
albiflorum L.,
subsp. stenopetalum, Senecio pseudaureus Rydb., and Viola adunca Sm.
It
grows with Botrychium lanceolatum (Gmel.) Angstr. subsp. lanceolatum,,
paradoxum W. Wagner, pedunculosum
B. minganense Victorin, B. H. B.
W. H. Wagner, and B. pinnatum St. John. The sites are valley bottom Quater-
nary reworked by the Lostine River or small tributar-
surficial deposits, locally
Hurwal
Adjacent slopes are sedimentary bedrock in the Triassic/Jurassic
ies.
Canyon and
Formation. In places the upper west wall of Lostine is granite,
the east wall pure limestone of the Martin Bridge Formation. It is possible
is
most Botrychium populations influenced by basic or
that or of the are cir-
all
morai-
cumneutral groundwater percolating through calcareous glacial or
till
may and
nal be no coincidence that the richest diversity greatest
debris.
It
canyons
abundance of Botrychium species are found in the calcareous of the
Wallowa Mountains, rather than in the granitic or volcanic basins.
We
aware populations of Botrychium hesperium in the
are of four extant
km
Wallowas. The Oregon range of the species is included in ca. 5.5 of river
and
valley. The total known number of plants at this time is less than 100,
they from suppression, pack animal grazing, wood-cutting,
face threats
fire
most
and despite the that or plants
recreation-associated activities, fact all
are within the Lostine River Wild and Scenic River corridor, a part of the
Wallowa-Whitman
Eagle Cap Ranger District of the National Forest.
AMERICAN FERN VOLUME NUMBER
240 JOURNAL:
92
3 (2002)
Collections oi Botrychium hesperium were made in 1981 [W. H. Wagner
first
81130 MICH), with WTU),
later collections in 1991 {Zika Alverson 11295
Er
1992 [Zika Alverson 11794 WTU), 1993 {Wagner 93047 MICH) and
Er et
al.
&
We
1996 [Zika Alverson 12908 OSC). were puzzled by
these plants
for
many
and
years, thought they might represent an undescribed
taxon, related
to B. hesperium, but with slightly angular upper pinnae and
shorter basal
pinnae. This was
a false impression, based in part on the large Wallowas
growing
plants in sheltered or partly shaded sites, and based on a limited
sample of B. hesperium from Oregon and elsewhere. To
get a better idea of
we
variation in B. hesperium, studied large living populations Montana,
in
Arizona and we
Colorado. Finally, as saw more Oregon plants, we con-
cluded they were
part of the natural variation of B. hesperium, united by
their grayish-green color, exaggerated and asymmetrical basal pinnae, broad
rounded upper pinnae, and ample
sporophores.
We
are pleased acknowledge our funding
to sources
for fieldwork: the
Native
Plant Society of Oregon, the Oregon Natural Heritage Program, and
We
Wallowa-Whitman
the National
Forest. are grateful specimens and
for
discussions of B. hesperium, provided by Peter Root, Peter Lesica, Kathy
and Don
Ahlenslager, Farrar.—Peter Zika and Edward
F. Alverson,
R.
Herbarium,
Dept. of Botany and Plant Pathology, Oregon
State University,
OR
Corvallis, 97331, and Warren H. Wagner [deceased) and Florence
S.
Wagner, Department
of Ecology and Evolutionary
Biology, University
of
Ann
MI
Michigan,
Arbor. 48109.
A
Binomial for the Hybrid Polypodium of Eastern North America.—Two
Polypodium
species of [Polypodiaceae) occur
in eastern North America,
the
appaJachianum Windham
diploid P. Haufler & and
the tetraploid
P. virginia-
num
These
L. species hybridize, producing
a sterile triploid recognized by
and
abortive spores intermediate morphology. The
its between
differences
these three taxa are well Wang
(Amer.
Bot.
J.
78:624-629. 1991) and Haufler and Windham
(Amer. Fern
81:7-23.
1991),
J.
The
triploid hybrid so far has been found only on the Appalachian
Plateau
where appalachianum
and
P. virginianum
P. are sympatric. The hybrid
has been documented
so far in Ontario, Canada and New
eight
states:
New
Hampshire,
North
Jersey, Carolina, Ohio,
Pennsylvania,
Tennessee,
Mono
technic and
Inst, State Univ., Blacksburg, VA. 117-146.
&
pp. 1970; Haufler
Wang. Mont
OD.
cit-
West
Virginia can be added
to this distribution, based upon specimens OS
and
at
WVU
and
provinces may
as well. Indeed,
the triploid prove
rather
frequent, as
Mont
above.