Thursday, August 29, 2013

Joshua Tree (Yucca brevifolia) and its sister species (Yucca jaegeriana) are vegetative icons of the arid, continental climate region of the southwesterly Mojave Desert floristic region.    By contrast, as iconic are oak woodlands of cismontane inverse – winter wet, maritime climate California.  The two are exactly inverse.

Lenz (Aliso 24:97-104. 2007) admirably shows that there are clearly two species of Joshua Tree – at this juncture neither taxon has been investigated with molecular methods.   The attached map is an approximation drawn from Little (1976) – red is the distribution of Yucca brevifolia Engelmann and green the distribution of Y. jaegeriana (McKelevy) L.W. Lenz.

The photograph is a site in Oak Creek Canyon, Kern County, in the Techachapi Mountains (15 April 2003, ca. 35.03218 -118.39499) where Yucca brevifolia reaches its most mesic incursion into, barely, cismontane California, thus barely within the California Floristic Province sensu stricto.

Might these extreme western-most Joshua trees have something going for them in the genome department?

Little, E.L., Jr., 1976, Atlas of United States trees, volume 3, minor Western hardwoods: U.S. Department of Agriculture Miscellaneous Publication 1314, 13 p., 290 maps.

Friday, August 23, 2013

Asymmetric Burl Sprouting in Wieslander’s manzanita

Arctostaphylos manzanita ssp. roffii is one of 6 recognized races of a common, often dominant, California manzanita.  The 6 tetraploid races of Arctostaphylos manzanita largely have allopatric geographic ranges.   The Roof manzanita is not a listed rare plant: it is a relatively uncommon however, and is narrowly endemic to the Cascade and North Coast ranges, with one central Sierran exception (SBBG50844)

The Ponderosa fire burned about;25,000 acres of Tehama and Shasta County in August, 2012.  Areas where I had seen and collected Arctostaphylos manzanita ssp. wieslanderi before the fire, I had not understood the differences between the two subspecies.  In the Ponderosa Fire, both were burnt to a crisp. In May, 2013 I revisited one site, and observed Arctostaphylos manzanita ssp. roffii resprouting.

In the instance recorded here, resprouting did not occurring over the entire burl.  Rather, the only resprouts were originating from below the soil (as seen at the 4 o’clock position on the photo of the burl).  In the present instance, it appears as if the fire was sufficiently hot so as to completely kill all of the exposed portion of the burl, leaving only the below ground parts viable.

Resprouting dymanics of chaparral shrubs following fire, including genetic signaling pathways and how they become activated, are a fertile subject for study.   Burn baby burn...

Photo: resprouting burl on April 25, 2013; ca. 5 miles E of Manton, Tehama County.

N.B.  on the original post, dated 8/23/2013, I mis-identified these plants as A. manzanita ssp. wieslanderi.  On April 11, 2014 I again visited the Ponderosa Fire region as part of my vegetation characterization studies, and confirmed that both infrataxa occur in the region.  A. manzanita ssp. wieslanderi lacks a basal burl, while A. manzanita ssp. roffii has a huge burl.  A. manzanita ssp. roffii is superficially similar to A. patula, which also lacks a basal burl (but does resprout epicormically after fire), and which occurs at higher elevations in the Battle Creek watershed.

Thursday, August 22, 2013

Post flowering calyx throat closure in monkeyflowers

Once upon a time (not so long ago, 2012, in a certain esteemed tome which costs $125), about 15 species of monkeyflower were submerged under the name "Mimulus guttatus".  Such a broad treatment is equivalent to submerging species of pine as distinct as Monterey Pine (Pinus radiata), knobcone (P. attenuata), and Bishop Pine (P. muricata) into one species.  For these pines, this is the viewpoint circa 1880. Ignorance is not bliss in the realm of biodiversity conservation.   Many monkeyflowers are rare endemics, and our understanding of their distribution and abundance is primitive.

Erythranthe guttata sensu stricto is a perennial with stolons.  Within Section Simiola, most species have a feature of the calyx after pollination that is distinctive.  In flower, the calyx lobes are of two size orders: the upper is longer, the other 4 are about equal.  Following anthesis, in E. guttata, the lower two calyx lobes curve upwards, accompanied by an expansion of the inter-calyx rib tissues.

We have all seen the touch-receptive stigma of a monkeyflower (or if not, ought to...).  The pollination trigger mechanism in this instance involves a set of genetic instructions independent of those related to fruit maturation.    Fertilization triggers more than one genetic regulatory pathway: 1) quick, make seeds, and 2) even quicker, make the calyx differentiate.  How?

Most of the ca. 40 species of  Section Simiola, including E. guttata, have the post-zygotic calyx differentiation feature to variable degrees: eight species do not (E. utahensis, E. glabratus, E. arvensis, E. michiganensis, E. inamoena, E. geyeri, E. regni, E. visibilis).  

Images: above, two flowers, the lower post-zygotic and the upper at anthesis; below, the two same flowers, the lower post-zygotic.

Thursday, August 15, 2013

Not breaking the Federal Listing logjam for the California flora

Federal Listing of rare plants in California has been in a log-jam for over a decade.  Over the last dozen years, only three plants have been added to protection under the Endangered Species Act.    The 1990s was a period when listing activity increased dramatically.  Over the past dozen years, listing has remained essentially static.  Endangerment threats to the California flora have been increasing over this period.

The recent, August 2013, proposal to list Ivesia webberi is the most recent activity.  Listing of this single taxon does not break the jam.  It actually just highlights a dozen year moratorium – a fact that in practice demonstrates that listing actions are a political and not a biological process.

On a biological basis, perhaps something on the order of 400 species of California plants quality for Federal listing, about twice the number presently listed.

Saturday, August 10, 2013

Polemonium chartaceum way out of range at Donner Pass, Nevada County, California

Polemonium chartaceum (CHSC3180) at Donner Pass
I hereby record that I did not relocate a Polemonium at Crater Lake, on the western flank of Boreal Ridge, Nevada County (ca. 7500 feet elevation), visited on Friday last.  The terse label on the specimen suggests that it was gathered on an ascent to the lake from Norden, to the south.  I obtained Crater Lake by driving to the summit of Boreal Ridge, thence to the lake and vicinity from the ridge proper. 

The immediate vicinity of the Crater Lake is an odd geologic setting in that the andesite (?) locally forms blocky (ca. 2 dm average diameter) patches largely barren of vegetation – not unlike typical habitat for the tufted-alpine polemoniums (Grant 1989)

The record CHSC3180 filed as Polemonium eximium is worthy of more study.  

First, the elevation of this record is an extreme low-elevation outlier, being located several thousand feet in elevation below the lowest known records for Polemonium eximium, which as you know is one of the highest-elevation limit vascular plants in the Sierra Nevada alpine.

Secondly Polemonium CHSC3180 has the membranous/chartaceous leaf bases which characterize P. chartaceum and its sister taxon P. eddyense, which are poorly developed in P. exemium    

Third, the geographic location is essentially distant from either taxon,  in being removed ca. 130 km from the population of P. chartaceum (proximal in the Sweetwater Mountains, Mono County), or, 300 km from P. eddyense on Mt Eddy, largely on the Siskyou County side, in far northwestern California.

An ascent and search from Norden is suggested.  My working hypothesis is that CHSC3180 is the sole collection of an undescribed taxon in the P. chartaceum-P. eddyense clade, geographically and mid-Pleistocene era isolated from its congeners.

Grant, Verne.  1989. Taxonomy of the Tufted Alpine and Subalpine Polemoniums (Polemoniaceae). Botanical Gazette Vol. 150, No. 2, pp. 158-169

Saturday, August 3, 2013

Shield-bracted monkeyflower (Erythranthe glaucescens) is probably 2 species

Shield-bracted monkeyflower (Erythranthe glaucescens (Greene) G.L. Nesom) is on CNPS List 4 and is narrowly endemic to the Cascade Range foothills of Shasta, Tehama and Butte Counties, California (a CNPS report from Colusa county is not supported by a specimen).

Erythranthe glaucescens  has been variously described as either annual  (Thompson 1993, 2012) or as also perennial (Nesom 2012).   Nesom (2012, p. 61) noted this discrepancy with the notation that all but two specimens were annual :

“Plants from one locality produced filiform, small-leaved runners from basal cauline nodes: California. Butte Co.: Canon of Big Chico Creek, 26 Mar 1914, Heller s.n. (MO) and 2 Jul 1914, Heller s.n. (MO). Mcnair did not say what observations led him to interpret the duration of E. glaucescens as perennial.”

Here I note that there are indeed perennial plants which are within the current circumscription of Erythranthe glaucescens, and more specifically, that there are likely to be two natural taxa involved, which implies that one taxon is not yet described.

Plants of Erythranthe glaucescens at JEPS109856 are clearly perennial: they produce abundant stolons.  In this botanical sense, stolons are stem organs which grow at the soil surface, or just below ground, which can also form adventitious roots at the nodes, and which proliferate laterally from a parent individual.    Stolons are commonly called runners (as used also by Nesom 2012).  By contrast, rhizomes are root tissue and mimic the same lateral expansion model (and are not involved here).

My review of specimens and photographs of Erythranthe glaucescens suggest to me that two taxa are being labeled as Erythranthe glaucescens.  If I were to venture a key to the Calphotos photos, it would be:

1.  Perennial, stoloniferous.  Foliage blue-glaucuous....0177 3303 3362 0079
1’  Annual, striclty so, foliage light green... 0000 0000 0407 3343

These differences are readily seen in the isotype (CAS792) which is well preserved, and annual, vs. my specimen JEPS109856 which is clearly a stolonifrous perennial.    The images are above (face of the diversion dam [upper photo, June 28 2006) and specimen (lower photo) in vivo collected there on 1 August 2013.  In my initial primitive analysis, there seems to be an elevation and habitat separation between the two putative taxa:  glaucescens is a vernal stream or seep annual of the foothills, while the undescribed taxon is a seepage-cliff specialist of conifer forest settings at mid-elevations.

Thompson, D.  1993 et 2012.  Mimulus, in the Jepson Manual (2 eds.)
Neosm, G.  Taxonomy of Erythranthe sect. Simiola (Phrymaceae) in the USA and Mexico.
Phytoneuron 2012-40: 1–123.