Hydrophytic vegetation of the San Joaquin Delta

With the revival of quasi-dormant debate over the Peripheral Canal/Tunnel,  I point out our poor understanding of Delta flora and vegetation in relation to salinity gradients.  Marsh salinity in the Delta region is suspected to have undergone a strong, directional increase associated with anthropogenic hydrologic modification.  I have not yet found a comprehensive analysis of existing vegetation salinity gradient relationships, and consequently wonder if any such study has been undertaken.  Predicting future vectors of marsh ecosystem change, and any but feeble hope for restoration, needs to account for pre-settlement flora and vegetation conditions in the Delta.

On July 17, 1896 Willis Jepson collected yellow pond lily (Nuphar polysepala) at Stockton.  Nuphar polysepala is a scattered, important member of the hydrophytic flora of Sierran lakes, mainly at about 7000 ft.  Nuphar does occur at low elevations, such as in Marin County, and other coastal lakes.  The occurrence of N. polysepala in the deltaic Great Valley is significant because this taxon is a indicator of water salinity: it is salt intolerant (1). 

Nuphar polysepala was still extant near Stockton at least until the early 1970s.  In the mid-1960s, it was still present in Pixley Slough.  In the 1970s, it was present near Snodgrass Slough near Locke, although this latter site was not recorded by Bowcutt (2).   Very probably, if salt water intrusion has taken its toll on the Delta hydrophyte flora, Nuphar would now be extirpated.  Is it? 

Several other hydrophytes are known from >60-100 yr old historical records in the Delta: Carex comosa near Holt in 1928, Meneyanthes trifoliata (3), Potamogeton nodosus in 1928, P. zosteriformis in 1949 etc etc.  Lycopus americanus, another non-saline hydrophyte, is apparently still present as of 2002. 

These non-saline hydrophytes are indicators of delta water quality and their local distribution, and their placement in a data-based gradient analysis of Delta marsh vegetation is needed.  

I poist that saline intolerant hydrophytes have been eliminated from much of the Delta region associated with the inland intrusion of brackish or saline waters.  If these non-halophytic halophytes persist today, their communities become a model for restoration.  Where might this persistent, original hydrophytic vegetation remnants be ?

1.  Padget, D. et al. 1999. American Journal of Botany 86(9): 1316–1324.

2.  Bowcutt, F.  1996. Madrono Vol. 43, no. 3, pp. 417-431.

3.  Mason, H.  1957. Flora of the Marshes of California. UC Press

Northern distributional limit of Juniperus californica

Over expansive portions of North America, juniper dominated vegetation is afforded ‘formation’ status: that is, a dominant, zonal ecosystem characterized by a single species (dominant in biomass and of trophic cascades), extensive, climatically-correlated vegetation type on a continent-wide scale.  In California, a Juniperus californica community has not been recognized at the higher-syntaxon level: in southerly California, Thorne (1) did not distinguish a Juniperus californica vegetation type where it is most abundant.  Certainly at lower syntaxonomic levels (associations), J. california communities are of ecological interest. California juniper rarely forms extensive stands in the northerly part of its geographic range.

The geographic range of J. californica has been little discussed in classical conifer synchorological literature: Jim Griffin and Bill Critchfield did not map Junperus california (2) probably because these foresters considered it to be 'not a tree'.  Conifer distribution maps offered up by Little (3), using his characteristic method whereby a radius envelope was drawn encircling each known site, shows the range of J. californica becoming more discontinuous  northward in California.  The range map in Adams (4) is generalized.

I will leave aside the fact that southerly Junipers related to J. californica should probably be afforded taxonomic segregation (perhaps as subspecies):  J. cedrociana on Cedros Island;  J. ‘californica’ on Guadalupe Island, which is considered extirpated; might be distinct, given the density of unique endemics in that flora.  Others in far south Baja?

Of considerable interest is the single specimen attributed to J. californica from the Klamath River canyon, Siskiyou County (SD51279), fully 100 miles north of Ash Creek.  What species is this?  A Juniper plexus-nexus might be indicated in the Klamath-Siskiyou ‘knot’ which perhaps still has some untying to do: Juniperus californica var. klamathensis L.F. Henderson, described from near Mt. Ashland, and considered a synonym of J. occidentalis (4), is at the far westerly extent of that arid, cold-interior tree.  Also of note is a disjunct outlier also being called J. occidentalis (2) in Trinity County.  All of these, again, indicate a Klamath-knot that merits study to untie; Vasek (6) found some of these westerly outliers to be chemically distinct.

Sudworth (5) reported J. occidentalis from the Canyon Creek Lakes watershed in the Trinity Alps: Griffin & Critchfield (2) guessed this report to be Juniperus communis (of Sect. Juniperus):  this report needs field survey, as the Canyon Creek watershed obviously has its own entangled ‘Klamath knot” in the guise of Bochera serpenticola, Sedum paradisum and other narrow endemics which grow there.

Northern Limit at Ash Creek

The northerly distributional limit of J. californica is at the very head of the Sacramento Valley,  specifically at Ash Creek, east of Anderson, which is tributary to the Sacramento River just north of the Tehama County line.  The colony of J. californica is scattered within a foothill savannah matrix of Quercus douglasii and Pinus sabiniana on very shallow, stony, volcanic-derived ‘soils’.   Specimens attributed to another Ash Creek (specifically CAS349187) are incorrectly mapped.  Other far N specimens are mis-labeled (CAS515186), these are J. occidentalis.

The Juniperus californica stand can be seen along the county road (Ash Creek Road) for several miles beginning at the low hills that begin just east of the Sacramento River crossing at Balls Ferry.   The site has not burned in recent times, and many trees are large ‘bushes’ – that is, about 3-4 meters tall and multi-trunked. 

References

1. Thorne, R.F.  1976.  pp. 1-31 in Vegetation of Southern California.  Calif. Native Plant Soc.

2.  Griffin, J.R. & W.B. Critchfield. 1976 (supplement).  USDA Forest Service Res. Paper PSW-82

3.  Little, E.L.  1971.  Atlas of United States Trees. Vol. 1. USDA Forest Service Misc. Pub. 1146

4.  Adams, R.P.  2011.  Junipers of the World: the genus Juniperus.  3^rd ed.

5.  Sudworth, G.B.  1901.  Forest trees of the Pacific slope.  USDA.

6.  Vasek, F.C.  1966.  The distribution and taxonomy of three western Junipers.  Brittonia 18:350-372.

The biogeographically correct eastern border of California's Klamath bioregion

In formulating the now well known Jepson bioregions for California, Jim Hickman made one significant error: he mis-mapped the geographic setting that differentiates the Klamath Ranges (KR) region from the Cascade Ranges (CaR) region.  Hickman’s boundary concept was correctly formulated: the Cascade region he characterized as “this volcanic region..” which contrasted with the Klamath Range region geologically,  which is also correlated with strong biogeographic pattern (along an aridity gradient from toward the interior).  However, in the 1989 edition (Hickman 1989), the map depicts the border that, in the color map and text in the 1993 Jepson Manual (Hickamn 1993), is “...more or less along of Interstate 5”. 

This border is geologically and biogeographically wrong.

Both geologically and biogeographically, the Klamath Ranges region includes about 250,000 acres of non-volcanic mountainous terrain comprising the McCloud arm, Squaw Creek arm, Pit River arm of Shasta reservoir, including the highest peaks in the reigon Grizzly Peak (6252 ft) and Bald Mountain (5536 ft), a region of metamorphic rocks.  The vegetation of the region has more in common with the Klamath Ranges than the Cascade Ranges, being forests largely dominated by Douglas-fir.  The region in question is home to two endemics I have described: Shasta boneset (Agartina shastensis) and Shasta Snow-wreath (Neviusia cliftonii), both with high fidelity for calcareous, not volcanic rocks.

The first figure shows the proposed, corrected border between the KR and CaR regions (red line) imposed on the map that appears in the inside front cover of both editions of the Jepson Manual.

Essentially, the border I suggest is exactly coincident with the extent of the Eastern Klamath terrane (Irwin 1994), which to the east is bordered by Quaternary and Tertiary volcanic rocks of the true Cascade ranges (yellow eastern border of the second figure).

References:

Hickman, J.C. 1989.  Introduction to the Jepson Manual.  Jepson Herbarium, University of California, Berkeley.

Hickman, J.C.  [Ed.].  1993.  The Jepson Manual, Higher Plants of California.  University of California Press.

Irwin, W.  1994.  Geologic Map of the Klamath Mountains, California and Oregon.  USGS Map I-2148.

Poison Oak (Toxicodendron diversilobum) is a fighter.  This post is short: and has a simple point.  Cant get rid of it at my house.

My house in coastal central CA [40 inches mean ppt, frost rare] had an undeveloped, adjacent lot when, in 1986, I moved in.  Hack, Hack, Hack again later, clearing trees, grubbing stumps, planting a garden later, one would presume that any plant I had overtly targeted for eradication would now be toast, 26 yr afterwards. 

Despite grubbing, despite Roundup, T. diversilobum continues to re-appear here and there.  The indication I take away is that the rhizome system is very much like that of a vagile invader such as Convolvulus arvensis; in which, when fragmented, tiny little fragments maintain, then gain, and continue demographic existence, as if awaiting a relaxation of control.  In my neighborhood, T. diversilobum assumed the two known growth forms: 1) lianas which grow via attachment roots (cf. Hedera, Araliaceae) to 100 feet in the crown of old-growth Sequoia sempervirens, or 2) bushy, highly branched ‘shrubs’.  The overall indication I intend with this post is that the phenotypic plasticity of  T. diversilobum seems to be under genetic control.   General purpose genotype?

Merits study with molecular methods.

Marble in Plumas County

Substrate controlled endemism IS the California flora: in one word; serpentine!  A secondary “hot spot” in our flora is limestone and/or marble.  Be it a big white flowered shrub, Neviusia, or a Heterotheca monarchensis, calcareous substrata are invariably worthy of exploration for new novelties or new records. 

In the Sierra, limestone and or marble occurs as isolated, small rock masses, often these do not get mapped at the 1:250,000 scale of the state geologic maps.  A systematic survey of these 'islands' is needed.

A calcareous site worthy of visitation is Marble Cone, in the Middle Fork Feather River.  At least based on CCH specimen records with coordinates, no collector has been in the vicinity.  Access seems, from the topographic maps at least, is uncertain, but 4WD roads get within about a mile upcanyon, or a trail about the same distance downcanyon. 

Someone, go yonder.

Lomatium ravenii, Hunzinger Flat, Lassen County, California?

NDDB EO#32 Lomatium ravenii at this site was reported in first in 2003, without citation of a voucher specimen, and without any subsequent revisits.  On June 6, 2012 I visited the site, and having also visited the type locality for L. ravenii (1 mile S of Ravendale) and nearby sites, am uncertain of the taxon of Lomatium present at NDDB EO#32 (1/4 mile N Hunzinger Flat, Lassen County, 41.09199 - 120.78617)

Lomatium ravenii was described by Mathias & Constance (1959).  It was treated as distinct by Constance (1993).  Cronquist (1997), however, did not recognize L. ravenii: rather, he submerged it within a wholesale variable and geographically widespread L. nevadense (with a geographic range over most of the northern Great Basin).

At the type locality of L. ravenii, and at nearby reported sites on the Madeline Plains, Lassen County, plants answering to L. ravenii have leaves that are subtly but distinctly different from the plants at  NDDB EO#32, being more finely dissected [that is, upon morphometric analysis, cf.  Carlson et al. 2011, would a) show a greater bifurcation ratio, and b) would have linear, fewer lobed terminal leaflet segments as compared to topotype material of L. ravenii).  Published manuals use flower color to distinguish taxa of Lomatium, and because these plants flower very early (often before regional road networks are passable and snowfree) flower color is often not evident on herbarium specimens.  The plants at NDDB EO#32 did not have purple flowers, but because flower color fades quickly in the yellow flowered taxa, such that spent flowers of both yellow and white flowered taxa appear similar in senescence, flower color of NDDB EO#32 was not evident on my visit. (I will also comment here than central Nevada material at NY attributed does not match the type of L. ravenii, and is probably undescribed)

Taxonomy of Great Basin Lomatium allied to L. nevadense is not resolved.  Lomatium ravenii has been attributed to a range across most of the central Great Basin (Constance & Weatherwax 2012).  However, plants allied to this group from eastern Oregon have been shown to be a distinct species, L. bentonitum (Carlson et al. 2011).

My specimen of NDDB EO#32 is more similar in leaf morphology to L. foeniculaceum var. macdougalii, as treated in TJM2 (Constance & Weatherwax 2012), at least compared to material attributed to this taxon from near Alturas, and material from central Oregon.  There is a unprocessed record for L. ravenii for the Lane Reservoir quadrangle, and if a second site is known, would be important to voucher if appropriate.  Notable in this regard that many reported occurrences of L. foeniculaceum var. macdougalii and L. ravenii from Modoc and Lassen counties are not vouchered.

A salient habitat difference pertaining to site occupancy for L. foeniculaceum var. macdougalii versus L. ravenii is related to substrate.  Lomatium ravenii, at least the type population, and other populations on the Madeline Plains, occur on fine, clay and silt, subalkaline lacustrine and aeolian deposits that form deep soils on sites that are seasonally flooded in the exceptional, infrequent wet year (see photo on Calphotos).  By contrast, L. foeniculaceum var. macdougalii occurs on tehpra deposits (material that falls out of the air associated with explosive vulcanism events).  At NDDB EO#32 the deposit is a volcaniclastic tephra that was entrained within a mudflow,  which subsequently set.  The parent material at the site has weathered sufficiently to have a high clay component in the soil.  However, the site is not subalkaline, but rather the soils are slightly acidic.   By contrast, the soil pH at sites I visited for L. ravenii ranged from 7.5 to 8.1 .  This habitat contract is suggestive that the plants at EO#32 are L. foeniculaceum var. macdougalii rather than L. ravenii.

It should be noted here that the revised Jepson Manual treatment attributed to Lincoln Constance was not extensively changed from his 1993 treatment (since he was not active by 1999 and died in 2001).  That fact posits the problem that some California endemic taxa would benefit from additional study, which, along with the recent description of other novel, narrowly endemic, rare taxa of Lomatium from the arid western U.S. (Helliwell 2010, Darrach & Wagner 2011, Darrach et al. 2011),  suggests further study of the entire genus is suggested, and that determination of the distribution and occurrence of rare taxon of Lomatium in northeastern California is far from resolved (cf. Soltis & Novak 1997, Gitzendanner & Soltis 2001).

Constance, L. and M. Weatherwax. 2012.  Apiaceae, in B.G. Baldwin et al. [Eds.], The Jepson Manual, Vascular Plants of California .  Univ. California Press.

Constance, L. 1993.  Apiaceae, in J.C. Hickman [Ed.], The Jepson Manual, Vascular Plants of California .  Univ. California Press.

Cronquist, A.  1997.  Lomatium, pp. 394-420 in A. Cronquist, N.H. Holmgren & P.K. Holmgren.  Intermountain Flora Vol. 3A.  New York Botanical Garden.

Carlson, K.M., D.H. Mansfield & J.F. Smith.  2011.  A new species in the Lomatium foeniculaceum (Apiaceae) clade revealed through combined morphometric and phylogenetic analysis.  Systematic Botany 36(2):495-507.

Darrach, M., K.K. Theib, B.L. Wilson, R.E. Brainerd and N. Otting.  2011.  Lomatium tamanitchii (Apiaceae), a new species from Oregon and Washington state, U.S.A.  Madrono Vol. 58.

Darrach, M. & D.H. Wagner. 2011.  Lomatium pastoralis (Apiaceae), a new narrow endemic species from Northeast Oregon.  J. Bot. Research Institute Texas 5(2):427-435.

Gitzendanner, M.A. and P.S. Soltis.  2001.  Genetic variation in rare and widespread Lomatium species (Apiaceae): A comparison of AFLP and SSCP data.  Edinburgh Journal of Botany 58:347-356.

Mathias, M.E. & L. Constance.  1959.  New North American Umbelliferae – III.  Bull. Torrey Botanical Club 86:374-382.

Soltis, P.S. & S.J. Novak.  1997.  Polyphylly of the tuberout Lomatiums (Apiaceae): cpDNA evidence for morphological convergence.  Systematic Botany 22:99-112.

Fimbriate desert-parsley (Lomatium foeniculaceum var. fimbriatum) near Alturas, Modoc County?

In California, Lomatium foeniculaceum is represented by 3 of the five races treated by Theobold (Brittonia 18:1-18. 1966) and Holmgren (Intermountain Flora Vol. 3A. 1997).  Records attribute all of the Modoc Plateau occurrences as Lomatium foeniculaceum var. macdougalii, CNPS List 2.2, a rare plant.

Holmgren and TJM2 keys respectively distinguish var. fimbriatum on the basis of “petals ciliolate margined (unique in the species)” and “petal margin minutely ciliate”.

Plants of the population of Lomatium foeniculaceum on the southerly outskirts of Alturas were in flower this year on May 16^th.  Plants in this occurrence have petals that are NOT glabrous on the surface nor on the petal margin, making them similar to the circumscription of var. fimbriatum.  The EO#10 plants do not have the very regular, minutely ciliate petal margins with glabrous petal faces illustrated in Intermountain Flora Vol. 3A p. 407.  Rather, they are have irregular, dense trichomes over both the petal surface and irregularly along the petal margin.

Many of the Modoc County locations of Lomatium foeniculaceum lack a voucher specimen, making determination of the petal glabrous/pubescent feature uncertain.   Lomatium foeniculaceum var. fimbriatum was described from a White Mountain, Inyo County type attributed to deposition at LA.  The holotype was not cited as seen by Holmgren (Intermountain Flora Vol. 3A. 1997) nor are any isotypes in any of the major herbaria databases (NY, MO, US, UC).   In the CNPS Inventory the statement is made "Lassen County plants may be undescribed".  Indeed, perhaps there is a 6th infrataxon of Lomatium foeniculaceum, one in which the petals are pubescent but regularly fimbriate as in var. fimbriatum.

The relatively poor photo shows a magnified image of the flowers and their abundant petal trichomes (red arrows show examples)