Wednesday, March 30, 2011

Matinal selfing in Camissonia lacustris




Selfing in Camissonia benitensis (Taylor 1990) was found to be direct and occurred before the flower bud opening. Here, I report the same similar matinal selfing in Camissonia lacustris, based on cultivated material derived from JEPS109727 collected at Wawona, Yosemite National Park.



Plants were sown out-of-doors in Aptos, CA on October 1st 2010. On March 30, 2011 the first flowers began to open. The photograph is of an unopened bud taken in early am, before opening. At this stage, the night before opening, the anthers are adherent to the spherical stigma, with abundant pollen. Under magnification, pollen tubes were observed under high magnification.



Thursday, March 24, 2011

Spot patterns in Yellow Mimuli












Mimulus, the "Monkey Flowers", with about 100 or so species, is nearly worldwide in distribution, with a concentration of narrow endemics in California, particularly in the central Sierra Nevada, where I work, is worthy of more genetic study: in this post, I pose the question, "why flowers with nothing but large spots only ".


The basis for the question is based on my inspection of the large array of yellow mimulus photos posted on the web (Calphotos, Flickr). In most of the species, combinatorial of spots occur on the corolla: many have 3 large spots on each of the lower corolla lobes, along with an array of smaller spots near the throat. In some species, individuals are spotless (i.e. M. primuloides, M. tilingii, M. floribundus and M. guttatus, of which the three photos show spotless, small spots only, and large and small spots conditions). In other species, some individuals have only small spots, and lack the 3 large spots.

NEVER, in all of the photos I inspected, did I find an individual with only 3 large spots whilst the smaller spots were absent. The genetics of spot inheritance and assortment are worthy of study; are large spots linked in some complex fashion such that when any spot genes are expressed, 3 large spots are mandatory?





Monday, March 21, 2011

Carex divulsa – the un-Berkeley sedge, invasive in California

Once upon a time, California native plant horticultural enthusiasts offered Berkeley sedge (Carex tumulicola Mackenzie, Section Phaestoglochin Dumortier) in the California trade. Sedges, being a perhaps the most speciose natural genus of angiosperms (perhaps 2000 species), are confused, is confusing, and confuse. Whence, a transposition occurred: Carex divulsa Stokes (also of Sect. Phaestoglochin), but native to Eurasia, was somehow conflated in the horticultural trade with C. tumulocola. The result: Carex divulsa is now sold widely: in California easily obtained, used frequently in "native" or "xeric" or "drought resistant" landscape plantings.




Carex divulsa, at least in mesic, coastal central California, is thus established. The photograph is of a seeding, one of many, that volunteered on the periphery of a C. divulsa purchased at a generic-grade garden center of a major hardware retailer (names withheld to protect the innocent).




Carex divulsa is neither xeric nor native. Its ecological preference in its native range is as a moderate to obligate mesophyte or subhydrophyte.




Carex divulsa will be spreading in Californa. One only has to visit the planting beds in the vicinity of the UC Santa Cruz Science Library to witness this: these plants are now, perhaps 8 yr after coming out of a 1-gallon can, clumps to 2 feet diameter and spreading babies about with abject rapaciousness.