Exclusively vegetative reproduction in Pennisetum clandestinum (Kikuyu grass) in Caifornia

Reproduction in kikuyu grass in coastal central California appers to be largely vegetative. In years of searching for flowering plants, I have never seen anything other than vegetative growth. The California Invasive Plant Council website treatment of this taxon notes that it can be spread via rhizome and stolon fragments. An amplification on what constitutes the invasocore unit of dispersal is in order: Pennisetum clandestinum produces swollen nodes which can also support dormant roots within the leaf sheaths. The entire nodal structure is the unit of dispersal, not in my observation the stolon fragments. Stolons are about 8 mm diameter or so, but when fragmented, the internodal segments do not seem to take.

The unit of dispersal might be termed a nodochore.

This coarse grass is a major invader of the coast side of the fairways at Pebble Beach, where its abundance vs. inland locations as opposed to Festuca rubra, indicates a significant degree of tolerance of salt spray.

Oak catkins and the carbon cycle

Accounting for pathways in the carbon cycle is now much like the state of cosmology before big telescopes: Hubble saw something in data, and, a few twists and turns later, PRESTO – the Big Bang Theory. Much if is not most of Earth's biosphere carbon stores reside in forests, either above ground or in soil. Being that I live in a forest (Sequoia sempervirens, Psedostugs menziesii, Quercus sheevei), and being that I attempt (vainly, perhaps) to manage organic matter accumulation on my roof (failed, miserably) and yard (difficult, but manageable), I can offer up a pathway observation which might be of note in illustrating the difficulty of modeling the carbon cycle. Acorn cups, acorn shells, and male catkins.

In the context I wish to broadcast, these four pathway compartments hold small stores of carbon, but the residence time therein is considerable, and thus in a model may be of sufficient magnitude to influence model verification. Oak acorns get eaten: the shells (pericarp) last for years. Their abundance is not minimal in some instances, but their decay rate seems glacial.

A modeler might not want to dwell on the problem of stored carbon contained in spent oak inflorescences, assuming the matter trivial. They, however, do not decay rapidly, they certainly last for more than a given year because in spring, when the oaks flower, for a period one can find last yr inflorescences scattered about after a big blow. Inflorescence parts are retained in the canopy for more than a single growing season.

Acorn cups of Q. shrevei seem to have a half-life that exceeds that of the acorn shells: perhaps by a year.

In redwood forest, the female cones of Sequoia sempervirens also behave much like Q. shrevei acorns: they are small, but last for years.

These little vignettes are just that – vignettes particular to a particular forest type. But the problem of vignettes is just that: in accounting for the carbon budget of forests, are little seemingly trivial stores such as acorn cups, female cones, and inflorescence remnants trivial, or do they warrant sampling. In my view, sampling the trivial pathways to demonstrate they are in fact trivial is not trivial.

 

 

 

 

 

Finding Subularia aquatic L. Awlwort taking a bath!

Finding Subularia aquatic L. Awlwort taking a bath!

At two Sierran locations this little aquatic has been collected flowering under water:

DWT #20352 Dog Lake, Tuolumne County, Yosemite National Park 40-70 cm of water Monday, August 18, 2008

DWT#20698 Johnson Lake, Madera County, Yosemite National Park, in waters to 2 meters deep, Wednesday, July 29, 2009

The southerly distribution station is East Lake, Tulare County:

John Thomas Howell wrote in the 1940 Base Camp Botany (Sierra Club outings section annual:

East Lake (15940). Some plants are found most unexpectedly. This particular plant was found when the botanist was taking a bath! When it first sprouts it is a submerged aquatic, but it doesn't bloom or fruit until the water recedes enough to leave it exposed to the air on the damp strand. While splashing around in the relatively warm (!) water for which East Lake is noted, the botanist noticed tiny plants which he had loosed from the bottom and which floated to the surface. These plants had no flowers but he lost little time in exploring the lake-shore in the vicinity and found there stranded plants in bloom. This inconspicuous plant is a circumpolarite localities chiefly north of East Lake. Since most botanists pass through life without ever seeing this intriguing little plant alive, aren't we glad we took a bath!

 

 

 

Franciscan Manzanita buried viable seed mitigation

The rediscovery of Arctostaphylos franciscana Eastw. [A. hookeri G. Don ssp. franciscana (Eastwood) Munz ] right in the path of a critical highway project and news reports of what is planned to mitigate the problem have not mentioned one critical factor: buried viable seed. Buried seeds are genetic individuals, and take under the endangered species act can be extended to include any removal of individuals from the gene pool. If we mitigate the problem only by propagation, and later planting ex situ, a take will occur because unique genotypes that exist only as buried viable seed will not be provided for.

 

It might seem a little fishy that the prior known sites for A. h. ssp. franciscana were on serpentine on Mt. Davidson, while the Doyal Drive site is (probably) on stabilized dunes (?), but both A. hookeri ssp. franciscana and A. h. ssp. ravenii Wells were once sympatric on Mt. Davidson (Roof, 1976 Four Seasons Vol. 5) whereas now both are reduced to single remnant individuals on non-ultramatic substrata. The substrate character of the Arctostaphylos hookeri ssp. franciscana site is relevant: buried viable seed might be well distributed both horizontally and vertically over a considerable distance about the newly discovered single bush if in fact the soils there are loose or sandy, and even if the soils are not sand, buried seed is someplace out there and vulnerable.

 

In order to fully mitigate potential impacts to Arctostaphylos hookeri ssp. franciscana, a program of salvage intended to capture buried viable seed will be required. Yes, it sounds nuts, but soil excavation and processing should be conducted. Volumes of soil excavated from the site need to be trucked to a experimental site, aliquots inspected directly for seeds, while the bulk needs to be processed to induce germination. How to do this: conduct research. Should the soil be cold stored until the research indicated how to proceed? Should the soil be mechanically scarified? Fire simulated? Again, conduct research.

 

A billion dollar highway project is not likely to be halted in spite of the rediscovery of an 'extinct' plant, but a fraction of the cost needs to be diverted to the conservation of the Franciscan Manzanita. A stimulus plan to gain a better understanding of manzanita biology is needed.

Epilobium oreganum – absent from the Sierra Nevada

It is my opinion that the name Epilobium oreganum Greene has been misapplied to plants of E. glandulosum ssp. glandulosum in the Sierra Nevada; plants with true 4-branched styles (topmost photo) have not been collected from the region. Presently, California Dept. of Fish and Game 'Rarefind' records have been corrected to reflect the absence of Epilobium oreganum in the Sierra, but the California Native Plant Society Inventory has not.

The problem arises because the key in Munz and Keck 1959 would direct long styled plants of E. glandulosum var. glandulosum to the name E. exaltatum E. Drew, which had a stated range in their Manual from the Sierra north to Oregon and Montana etc. Epilobium exaltatum E. Drew is a straight synonym of E. oreganum Greene, so the Munz & Keck application of that name was incorrect.

Several specimens were cited in older versions of NDDB as E. oreganum Greene from the Sierra:

JEPS72727 (EO#30) has not been annotated. I have inspected the specimen, but did not annotate it. My opinion is that the specimen is E. glandulosum var. glandulosum.

JEPS89974 (EO#36, Tulare County) is E. oregonense not E. oreganum.

UC1187138 (EO#39) is a specimen of E. oregonense

EO#40 & 41, 42, & 43 are records based on Gordon True's Nevada County Plant List, which in the list (my edition is 1973 mimeographed version) are records for E. exaltatum Drew, so again are E. glandulosum var. glandulosum

NDDB EO#29 is a report by Ledyard Stebbins from Wrights Lake. In his Wright's Lake Flora, Ledyard applied the name, probably Epilobium exaltatum via Munz's key, to this collection. Ledyard and Jack Major shared a cabin at Wrights Lake, and as their student, I was there many times. The plants grow in the meadow north of the cabin, and I have revisited and recollected the material, which is clearly E. glandulosum var. glandulosum (see the lowermost photo above). I suspect Ledyard's uncertainty is owing to the fact that c&nSNH plants of E. glandulosum var. glandulosum have occasional outgrowths of the stigmatic surface, which if not carefully inspected as high magnification [and particularly if the style is loaded with pollen] can appear as style branches.

Epilobium oreganum has truly 4-branched styles (see topmost photo above) and slightly zygomorphic flowers, features which you can readily see in the photo. My photo in Calphotos (0000 0000 0704 0293 (2004-07-11), the lowermost photo above, is E.glandulosum var. glandulosum: these plants had styles which are truly clavate with non-zygomorphic flowers, but the styles have warty outgrowths that could be confused with style branches. The 4-branched style condition in Epilobium shared only by other very distinctive species (E. luteum, E. niveum E. obcordatum, key couplet 14. in the Jepson Key).

So, it is my position that Oregon fireweed (Epilobium oreganum) does not occur in the Sierra Nevada, and that it is possible to mistake plants of E. glandulosum var. glandulosum that have warty outgrowths on the style as having branched styles, and thus misapply the name Epilobium oreganum.

Epilobium oreganum is a narrow endemic of the Klamath Region in Del Norte Glenn, Humboldt, Mendocino, Shasta, Siskiyou, Tehama and Trinity counites in California, and Josaphine, Jackson and Douglas counites, Oregon.

Pseudo-vivipary in Sisyrinchium bellum

Vivipary is defined as the precocious and continuous growth of the offspring when still attached to the maternal parent; in the case of plants, it would pertain by definition to the continual growth of the embryo, essentially germination before it ought to occur. Mangroves are viviparous. Ordinarily, plant embryos undergo a period of quiescence, the genes which code for molecular cascades that govern embryo dormancy and subsequent release to growth are still not well known. and perhaps I don't want to know all of their little quaint molecules anyways.

In FNA Vol. 26 vivipary is attributed to blue-eye grass (Sisyrinchium) with the statement "White flowers may occur in otherwise blue-flowered species, and vivipary occasionally occurs". My observation of Sisyrinchium bellum suggests that the purported yivipary is not vivipary per se, but is rather considered pseudovivipary.

In Sisyrinchium bellum, the inflorescence nodes develop subsidiary vegetative axes which initiate and develop well after flowering; resulting in vegetative reproduction. The inflorescence axis in large, perennial races of S. bellum arch downwards, and the nodes are often in contact with the soil, resulting in vegetative expansion, but hardly is this vivipary in the strict sense. This feature is variable in nature, and rarely have I seen it in grassland settings. However, Sisyrinchium bellum is also a weed-of-sorts in forested-setting gardens like mine in the Santa Cruz Mountains of California.

The pseudo-vivipary feature can be clearly seen it the photo of the voucher specimen, JEPS109033.

Mt. Dana Lupine – Lupinus danaus

Lupinus danaus was described from a collection made by Henry N. Bolander (#5087) labeled as "12,500 ft" on Mt. Dana [see the image of the isotype US321123 above, oriented as in nature]. In the Jepson Manual, the taxon is not treated. Munz & Keck (1959) treated it as a variety of L. lyallii. Variation in the Lupinus lepidus group is complex: Barneby (Intermountain Flora Vol. 3B 1989) offered a classification that placed these dwarf perennial lupines in context, but did not deal directly with the var. danaus since it is considered exclusively Sierran.

This summer I observed Lupinus danaus in vegetation sampling many times. The holotype and the plants in the field share the feature of having prostrate, very sparsely leafy peduncles that arch upwards only distally, such that the inflorescence is displayed upright at a short 1-3 inch distance from the actual rosette, which is very sparsely leafy indeed. This feature is not one that I have seen in photos of Lupinus lepidus var. lobbii, and it in fact may be a feature equal to those which Barneby used to recognize other variants of Lupinus lepidus, and hence the combination Lupinus lepidus var. danaus might be indicated. Thus, at least as the plants appear in the field, they differ consistently from var. lobbii, which has relatively shorter erect peduncles [Barneby's "development and attitude of peduncles"] or perhaps also "spatial relationship between foliage and raceme".

Whether or not the peduncle feature of the putative var. danaus is under genetic control is the central question.

Munz & Keck (1959) gave the range of Lupinus danaus as "Sierra Nevada north to Warner Mtns, w. Nev." [the latter would be Mount Rose, NV].

below I have scanned Barneby's comments verbatum [ my emphasis added] from Intermountain Flora p. 257 for consideration of the problem:

Dwarf perennial lupines are far less numerous in the Intermountain region than the teeming multitudes of L. argenteus, but they are almost as difficult to classify and consequently have acquired similarly extensive literature and synonymy. The characters that contribute to the individuality of an individual plant, to a population of similar plants, or to a conceptually idealized taxon are almost all quantitative and without exception independently variable. The most obvious are the degree of caulescence and mode of branching, the length and orientation of hairs, the size of leaves, the development and attitude of peduncles, the spatial relationship between foliage and raceme, the average length of raceme and density of flowers along its axis, and the size of petals. From early times these have been the external markers by which taxonomists have attempted to discover comprehensible order in this vexatiously difficult group. Detling's analysis of L. lepidus and kindred forms (1951) demonstrated the continuity of variation in all observed character states, and his conservative taxonomy, strongly conditioned by facts of dispersal and ecology, was adapted by Hitchcock (1961) to the dwarf lupines of the Northwestern flora and best harmonizes with standards accepted elsewhere in Fabaceae. It cannot be denied that a measure of undesirable simplification is inherent in this approach to Lupinus. Indefinitely numerous individual populations of dwarf lupines or small groups of such adapted to a particular habitat or confined to a particular region certainly do possess an idiosyncratic facies derived from a particular syndrome of characters. They are especially marked among geographically disjunct alpine or subalpine races of the aggregate L. lepidus var.lobbii and among the races of var. aridus remotely scattered in austere valley habitats over eastern Nevada and southeastern Oregon, no two of which seem exactly alike at all points. Undue emphasis on differences between these minor races leads inexorably to the quick sands that ultimately engulfed Charles Piper Smith. On the other hand wider, more comprehensive specific and infraspecific concepts suffer progressively from lack of definition. Most varieties of L. lepidus are truly dwarf lupines, with low tufted or diffusely matted foliage and stems reduced to a few short internodes or to columnar caudex-branches sheathed in stipules. The vars. confertus and ramosus however, have well developed primary stems sometimes giving rise to axillary fertile branchlets and therefore resemble in habit forms of L. argenteus. The dorsally glabrous banner and persistent floral bracts either singly or together distinguish these taller varieties of L. lepidus from all of L. argenteus.