SAGINA CAESPITOSA (ALSINACEAE) IN COLORADO, U.S.A

2009·2.5 MB·

by  A E Porsild

COLORADO,
SAGINA CAESPITOSA (ALSINACEAE)
IN
U.S.A.
WA
Weber
and Wittmann
Porsildt
A.E. R.C.
Museum Museum
Canada
National of University of Colorado
CANADA
UCB USA.
Ottawa, Ontario, 265, Boulder, Colorado 80309,
edu
weber@colorado.
bill.
we
In this note, report Sagina caespitosa Vahl) Lange in HJ. Rink for Colorado and the United States.
(J.
Nu-
North America Newfoundland,
Otherwise, occurs in in Greenland, Manitoba, Labrador,
caespitosa
S.
and Quebec (Crow
navut, 2005).
According to the Flora of North America (Crow 2005), two species of Sagina occur in Colorado, namely
many we common
saginoides and procumbens. For years, assumed that our only native species was the
5.
S.
saginoides. Erling Porsild visited in 1950 and the senior author took him, as he has Eilif Dahl, Eric Hulten
S.
Mount many
and European on
other botanists, excursions 14000-foot Evans, the of significant
field to site
(Weber have
alpine or arctic disjuncts 1965, 1991). Since then, the authors repeatedly collected Sagina there
Wendy me
and
at similar Recently, Dathan, Porsild's biographer (manuscript in preparation), sent a
sites.
how
copy of the page in his field notebook where he mentioned collecting Sagina caespitosa and thrilled
Hudson
he was, since he had not seen since Bay and Greenland. To Porsild should go the credit for the
it
discovery.
Sagina caespitosa has been considered an Amphiatlantic species; however, in Colorado locally
is
it
abundant on high mountain summits from 12000-13500 (3700-4100 m) on and
altitude, frost boils
ft
known
well-developed gravelly moss tundra. Throughout the remainder of range, caespitosa not to
its S. is
grow
than 1500
elevations greater (450 m).
at
ft
A
(Lindblom) from Colorado by Rydberg was overlooked
report of Fries (1906, 130) until
nivalis
S. p.
recently. Rydberg's report was erroneous, based on a Harry Patterson collection which here assigned to
is
being species of the American might also be expected in Colorado, but thus
caespitosa. a arctic,
S. S. nivalis,
far has not been detected; however, nivalis does occur in a few localities in Montana.
S.
it
In the Flora North America (Crow 2005), Sagina saginoides H. Karsten was described as "Plants
(L.)
of
and
perennial, tufted or becoming caespitose in alpine habitats." This is incorrect all collections of S. caespitosa
COLO
Herbarium were by
at annotated as S. saginoides. In the field, S. caespitosa is easily distinguished its
by by
tightly massed, button-like form. Plants are also characterized short shoots lacking internodes,
stiffly
erect pedicels, by plump, purplish sepals, and by petals equaling or slightly exceeding the calyx. occurs
It
make
on mature gravelly tundra usually at very high altitudes. The shoots can hardly be separated to less
bulky herbarium
specimens.
Sagina (Lindblom) Fries might be expected occur in Colorado, since a western American
nivalis to is
it
arctic species that reaches northern Montana. differs from caespitosa by being 4-merous with petals
It S.
shorter than the and by not being densely caespitose because of the lack of secondary shoots.
sepals,
Sagina Fenzl very weak, often somewhat procumbent plant with obvious internodes,
saginoides a
(L.) is
mud,
and on wet sand and
filiform pedicels pale white sepals. habitat not special, occurring or gener-
Its is
it
occurs lower
ally altitudes.
at
Journal of the Botanical Research Institute of Texas 3(2)
dbyRydberg(1906)] [out
i
ACKNOWLEDGMENTS
We
thank Crow and Wendy Dathan Del Wiens kindly reviewed the ms.
Garrett for assistance.
REFERENCES
2005. Sagina. of North America Committee, eds. Flora of North America North of
Crow, Flora Editorial
G.E.
In:
5:140-147.
Mexico.
estimated.The Reindeer Manuscript preparation.
Dathan, P.W. 201 Botanist: Alf Erling Porsiid. in
Mount Guidebook one-day
Weber, W.A. 965. Evans, concentration point for Pleistocene relict plants. for field
1
conferences, Boulder Area, Colorado. International Association for Quaternary Research, Vllth Congress. Pp.
10-12.
Mount
Summit
W.A. 991. The alpine of Lake, Evans, Colorado. 15(4):3— 15.
Weber, flora
1