ISSN 1188-603X

No. 437 May 31, 2011 Victoria, B.C.
Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2


From: William A Weber [Bill.Weber@Colorado.EDU]

Dear Adolf,

I don't recall if I told you that I am back in the herbarium after the ten years exile. The move was made while I was away in February on a trip to the Antarctic. Also, our fourth edition of the two-volume Colorado [vascular] Flora is in press; I have just seen the cover design, so we are expecting publication later this year. This has been a very challenging revision. We have had to decide which FNA changes we are willing to accept and what to reject. It is good to see that our continued use of paraphyletic groups as genera is gaining support elsewhere if not by FNA. Rydberg and I are no longer the pariahs they made of us.


William A. Weber
Emeritus Professor and Curator
University of Colorado Herbarium (COLO)
350 UCB
Boulder, CO 80309

P.S. What can we expect from the new Colorado Flora? But I would appreciate it if you could announce that the University Press of Colorado is publishing, in September we hope, of the fourth edition the two-volume Colorado Flora, east slope and west slope (Weber & R. C. Wittmann). We have worked our guts off deciding what to do with the clashing notions of the DNA/cladistics boys, and have put in a lot of interesting reading and references. One special feature is that we will be adding Don Farrar's up-till-now unpublished treatment of the moonworts, covering all of the Rocky Mountain states. We will also have an additional introduction outlining the history of this book series starting in the 1940s. It will be a very useful summary of my work over the years, and quite unusual for a field guide!


From: Kem Luther []

On April 30, 2011, about half a dozen Yellow Montane Violets (Viola praemorsa Dougl. ex Lindl.) were found in Devonian Regional Park by a survey team that was participating in the 1st ever Metchosin BioBlitz. The plants were initially discovered by a birder, Ian Cruickshank. Ian showed the plants to Gerry and Wendy Ansell, who confirmed Ian's identification and took photographs. Matt Fairbarns has viewed the stand and submitted the record to Conservation Data Centre, Victoria. This is the first confirmed appearance of the violet in Metchosin. Its status is Endangered (COSEWIC, SARA) and Red-listed in British Columbia (G5T3T5-S2).


From: Frank Lomer, Honourary Research Associate, UBC Herbarium, Vancouver, B.C. e-mail:

Megalodonta beckii (Torr. ex Spreng.) Greene - Asteraceae

A widespread aquatic in southern BC, it is known in the Fraser Valley only from Devil's Lake, Errock Lake (V: Ceska & Mitchell 1193) and Deer Lake (UBC: Warrington 608) in the eastern Fraser Valley. It rarely flowers in our area, but the opposite divided filiform leaves are unlike any other aquatic species here.

Muhlenbergia glomerata (Willd.) Trin. - Poaceae

Although this grass was collected by John Macoun from "damp places", Agassiz in 1889 [CAN: Macoun (22) 29,396], I had assumed this was a label mix-up as this species is not otherwise known west of the Coast Mts in BC. Surprisingly, in 2010 I discovered a population in a wetland east of Agassiz. It appears there is some calcareous influence from what looks to be a limestone patch on the mountain slope above the site.

Muhlenbergia glomerata occurs extensively in calcareous sites throughout eastern and central BC as well as the extreme north. So it is no longer of conservation concern in BC, though this west coast site is remarkable.

Myriophyllum hippuroides Nutt. ex Torr. & A. Gray - Haloragaceae

In BC this species is known only from the Fraser Valley, mainly on the north side of the Fraser from Pitt Meadows (UBC: Brink & McHale s.n.) to Mission, but also east to Harrison Mills (V: Ceska et al. C019). It can form dense stands in quiet water a meter or so deep and thrives in deep ditch sloughs and stagnant tidal backwaters. It is not as yet, on the whole, threatened by any development pressures.

Myriophyllum pinnatum (Walt.) Britton, Sterns & Poggenb. - Haloragaceae

A very local species of wet shores, boggy pools and ditches, and pools in emergent tidal flats. Known in BC only from a relatively small area along the Pitt River from Port Coquitlam (Minnekhada Regional Park - see Ceska & al. 1997) to Pitt Lake (UBC: Ceska 30362) and east of Lake Errock (Ceska & Ceska 30367). Also known from Washington (WTU: Zika 20196) and Oregon (V: Ceska & Ceska 26898; WTU: Zika 23482).


Ceska, A., O. Ceska & F. Lomer. 1997.
Myriophyllum pinnatum, a new species for British Columbia. BEN # 171 July 30, 1997

Myriophyllum ussuriense (Regel) Maxim. - Haloragaceae

This species has an unusual range. It is native to Asia and occurs in North America only in the Pacific Northwest; the main part of its range being in S BC and the Columbia River in the US (Ceska et al. 1986; Christy et al. 2000a, 2000b). It is restricted to emergent muddy and sandy shores where pools ollect at least for part of the summer.

In the Fraser Valley it grows from the Fraser delta to Harrison Lake. In Greater Vancouver it is known from about 20 sites along the Fraser and Pitt Rivers from Richmond to Pitt Lake to Barnston Island. The bulk of the Lower Fraser Valley plants are male. Female plants have been rarely seen in the Pitt River populations, but occur more commonly in the central and upper valley. Populations in the Fraser Valley are fairly secure because the habitat (muddy tidal flats) is not yet under development pressure. This will likely change in the future.


Ceska, O., A. Ceska, & P.D. Warrington. 1986.
_Myriophyllum quitense and Myriophyllum ussuriense (Haloragaceae) In British Columbia, Canada. Brittonia 38: 73-81.
Christy J.A., O. Ceska & A. Ceska. 2000a.
Noteworthy collections - Oregon. Myriophyllum ussuriense (Regel) Maxim. new in Oregon. Madroño 47: 212.
Christy J.A., O. Ceska & A. Ceska. 2000b.
Noteworthy collections - Washington. Myriophyllum ussuriense (Regel) Maxim. new in Washington. Madroño 47: 212-213.

Persicaria hydropiperoides (Michx.) Small - Polygonaceae

A locally abundant species of sloughs, wet ditches, boggy pools, emergent lakeshores and ponds in the Fraser Valley from Vancouver to Popkum. Known from 11 sites in Greater Vancouver, it is especially frequent in the central

valley around Chilliwack (UBC: Penny & Hartwell 186). It forms loose mats in shallow water with a muddy substrate, often covering whole shorelines. It does well in the deep ditches bordering agricultural fields, often Fringing a dense border of Phalaris arundinacea L. It is recommended for removal from the British Columbia rare plant tracking list.

Persicaria punctata (Elliott) Small - Polygonaceae

This annual or perennial species is much like Persicaria hydropiper (L.) Spach, but is much less common. Ripe achenes are the best way to tell these two apart. Persicaria punctata is known from moist sites that are often disturbed. It is known from 8 sites in Greater Vancouver (UBC: Lomer 90-109), as well as an historic collection from Agassiz. It appears not to be threatened because of its ability to spread during disturbance, though its wetland habitat is often under threat. Populations are sporadic from year to year, but appear to be stable overall.

Pleuropogon refractus (A. Gray) Benth. ex Vasey - Poaceae

A very rare grass in the Fraser lowlands. Populations are known higher into the mountains on the north shore of the river. It grows in shaded wet sites usually by clear flowing streams and freshwater seeps. The nearest sites in the Fraser Valley are on the Seymour River (UBC: Lomer 97-67) and into the mountains in Coquitlam.

Potamogeton nodosus Poir. - Potamogetonaceae

This red-listed aquatic has proven to be quite rare in BC. The only sites recorded in BC so far are Burnaby (UBC: Lomer 89-199), Hatzic Lake (V: Nijman & Soar 2864), Fort Langley (V: Ceska et al. 1549), Pitt River (V: Mitchell 1675), Seabird Island (V: Nijman & Baillie 4696); Mission (V: Ceska et al. s.n.) in the Fraser Valley, and in the North and South Okanagan. Much more searching is needed to determine the full extent of its range in the Fraser Valley.

Potamogeton oakesianus J. W. Robins. - Potamogetonaceae

Not much is known of this aquatic species. It is known from near Mission (Ceska & Ceska 1980) and is to be expected in other lakes in the Fraser Valley, but so far new sites have not been found.


Ceska A. & O. Ceska. 1980.
Additions to the flora of British Columbia. Canadian Field-Naturalist 94: 69-74.

Potamogeton strictifolius Benn. - Potamogetonaceae

Not much is known of this aquatic species. In British Columbia it was first collected in Windermere Lake in 1972 (V: Newroth 2757). In 1977 it was collected in Kawkawa Lake near Hope (V: Warrington 4836) and reported by Ceska & Ceska 1980. It is to be expected in other lakes in the Fraser Valley, but so far new sites have not been found.


Ceska A. & O. Ceska. 1980.
Additions to the flora of British Columbia. Canadian Field-Naturalist 94: 69-74.

Pyrola elliptica Nutt. - Pyrolaceae

Usually a species of montane forests, this rather widespread evergreen herb occurs on islands in the Fraser near Agassiz (UBC: Lomer 6400). It is known from higher elevations in the Chilliwack Valley and there is an old collectionfrom Port Haney (Maple Ridge) in 1897 (UBC: Henry 26). It is to be sought in shaded coniferous forests in the area.

Rupertia physodes (Dougl. ex Hook.) J. Grimes - Fabaceae

This is an unexpected species in the Fraser Valley, but there is a small population still extant in south Surrey near the Langley border (UBC: A. Guppy s.n.). I would not expect it to occur elsewhere in the Fraser Valley, Though there may be other sites in the vicinity. It is associated with Salal in well drained gravelly sites and can spread into disturbed areas.

Salix sessilifolia Nutt. - Salicaceae

It appears this species is restricted to the Fraser Valley in BC. Though of relatively limited distribution, Salix sessilifolia is a dominant species of sandbars and sandy banks of the Fraser from Steveston to Hope, as well as up the Pitt River to Pitt Lake, Harrison River to Harrison Lake, and odd outliers such as at Silver Lake (UBC: Ceska 24171). It covers numerous Fraser River island shores especially in the upper Fraser Valley wherever Sandbars form. Threats are few and it is well adapted to shifting sand and disturbance with its widely spreading root system and ability to sprout up from burial and cutting. It is too abundant and unthreatened to be called rare. Recommended for downlisting after several new sites are reported.

Sanguisorba menziesii Rydb. - Rosaceae

This perennial herb is believed to be derived from hybrids between Sanguisorba officinalis L. and S. canadensis L. Sanguisorba officinalis Is infrequent in sphagnum bogs in the Fraser Valley, mostly on the north shore of the Fraser River, while S. canadensis is found in the mountains on the south side of the Chilliwack Valley. Sanguisorba menziesii looks somewhat intermediate between the two, with heads of purplish flowers with dangling stamens. There is an historic record from Haney in 1949 (UBC: Krajina s.n.). It is expected to still be extant in the bogs on the north side of the Fraser River, but otherwise has gone unreported in recent times.

Sidalcea hendersonii S. Wats. - Malvaceae

This outstanding perennial with the hibiscus-like flowers is rather rare and sometimes threatened in its range outside of British Columbia (Love 2003). It grows along the coast from Oregon north to a recently discovered Population in Alaska (ALA Anderson 622 - V: photo). So new records north of

Vancouver Island are to be expected. For the species, the bulk of the Population resides in the Fraser delta from Iona Island south to Westham Island with scattered sites inland around Boundary Bay in Delta and Surrey (UBC: Prange 19).

I estimate more than 90% of the British Columbia population can be found Along the tidal shores and islands of the south arm of the Fraser River in Richmond and Delta. Indeed, it appears more than 75% of the world's population of Henderson's checker-mallow grows along this 23 km stretch of river. It is common and co-dominant in vast areas of tidal swamp with Carex lyngbyei Hornem. and_Phalaris arundinacea L. It is mainly an estuarine species that grows as far east in the delta only to Surrey, though there is an historical record from Milner in Langley.


Love, R.M. 2003.
Henderson's Checkermallow (Sidalcea hendersonii): Part 2. Summary of what is currently known about the global distribution of Sidalcea hendersonii (Malvaceae). BEN # 306 March 22, 2003

Sphenopholis intermedia (Rydb.) Rydb. - Poaceae

Collected from dredged sand in Surrey, east of Vancouver (UBC: Lomer 93-73). This grass is known from the Thompson River, as well as other sites in BC, so seeds were probably washed down into the Fraser and sprouted in the dredging. In 2010 a single plant was observed on the sandy meadow shore of an island in the Fraser River southwest of Agassiz. So it appears this species can arise naturally from material washed down the Fraser River from interior sites, thus it should be considered native here.

Verbena hastata L. var. scabra Moldenke - Verbenaceae

Local in the Okanagan, very rare elsewhere in BC. This tall, erect, purple-flowered perennial was collected in Vancouver in 1917 (UBC: Perry s.n.), but decades passed before it was noted again in the Fraser Valley, this time near Chilliwack. Surprisingly it is not known from purely natural sites here such as along the Fraser River, but does occur in disturbed ground, wet fields, roadsides and ditches. Presently known from three sites. All populations are endangered by development. A large population by Hwy 1 and Annis Rd., southwest of Rosedale, was lost in 2008 to cornfield expansion, though it survives in the periphery. The Port Coquitlam site has been destroyed by a housing development, though some plants have remained in the disturbed ground fringing the development. A third site near Bridal Falls was discovered during the 2008 CDC survey (UBC: Lomer 6781). It is a small population in disturbed ground and may not persist through succession.

Wolffia borealis (Engelm. ex Hegelm.) Landolt ex Landolt & Wildi - Lemnaceae

Rarely seen in the Fraser Valley (Ceska & Ceska 1980), this miniscule plant looks like nothing more than green scum. It is proving to be more common than first thought, but is rather sporadic from year to year. New sites from Cultus Lake, Vancouver (UBC: Lomer 6754) and Cheam wetlands suggest it occurs from one end of the Fraser Valley to the other, especially in the central valley. It is not endangered as long as there are sloughs and Typha ponds and lakeshores. Easily overlooked, but uncommon nevertheless. It often grows with Lemna and Spirodella and is presumably spread by ducks so it can show up just about anywhere that ducks feed and where water is adequate. It can have explosive exponential growth late in the season, but is so tiny that only several square meters are covered in most instances.


Ceska A. & O. Ceska. 1980.
Additions to the flora of British Columbia. Canadian Field-Naturalist 94: 69-74.

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