We report on growth and survivorship of two cohorts of blue oaks Quercus douglasii Hook. & Arn. (Fagaceae) monitored at Hastings Reservation in Monterey County, California, the first growing in an unprotected old field and measured as seedlings in 1965 and the second planted as acorns in 1985 in several sites differing in their degree of protection from grazing. Growth of all individuals was extremely slow: among those surviving in the first cohort, mean (± SD) height in 2006 was only 76.7 ± 45.0 cm for an average growth rate of 1.8 cm yr⁻¹, and only one of the original 73 oaks had grown taller than 1.5 m while one was still a seedling 28 cm in height 41 yr after being first marked. Of the second cohort, mean height 21 yr after planting was 54.3 ± 31.4 cm. None of these latter individuals had grown out of the sapling stage while 25% were still seedlings < 30 cm in height. Growth of this second cohort was significantly greater when protected from grazing and when growing in the open rather than in the shade. Although growth was slow, survivorship of oaks first measured in 1965 was high, indicting that individuals can live for decades despite significant grazing pressure. Our results confirm the difficulties of inferring age from size of blue oaks, since individuals just achieving the height at which they are typically cored may be 50 or more years old. They also indicate that regeneration, although very slow, can occur in open oak savannas in California despite significant grazing pressure. Whether the observed amount of regeneration is sufficient for long-term sustainability will require continued monitoring and modeling of oak demography.

The calcareous soils in the San Bernardino National Forest host a group of endemic plant species, including five listed as federally endangered. The parent material for these soils is a very pure deposit of magnesium and calcium carbonate that is being actively mined. The mining operations produce copious quantities of dust. This study evaluated the quantity of dust moving across the landscape and depositing to the ecosystems, and the effect of carbonate dust on physiological parameters of a plant species acting as a surrogate for the endangered species. Most of the dust was found to deposit within one kilometer of the mining operations. Plants growing within the deposition zone had lower photosynthetic activity and less vigorous growth patterns. Several mitigation measures are recommended.

Mammillaria gaumeri (Britton & Ross) Orcutt (Cactaceae), an endemic plant of the Yucatan Peninsula, is included by the Mexican government in the list of species that require special protection. Its natural habitat is now restricted to fragmented areas and protection programs involve botanical gardens in growing individuals rescued from disturbed areas. Little information is available on the reproductive characteristics of this species and nothing is known of its pollinators. We investigated the visitors of M. gaumeri flowers, collecting and observing bee species in its natural habitat (i.e., coastal dune) and in a botanical garden, where coastal dune vegetation had been created. Observations were made on plants whose density was artificially increased by grouping flowering individuals. At each site, we: 1) collected insects visiting the flowers; 2) recorded number of visits; and 3) video-recorded bee movements on the flowers. As expected, the number of bee species and visitation frequency were higher at the botanical garden than at the coastal dune. After landing on a flower, bees either inspected the anthers or dived among them. These behaviors, carried out by all observed species, seemed related to the state of the anthers (full or empty of pollen) and stigma lobes (opened or closed). Specifically, visits lasted longer when anthers were full of pollen and stigma lobes were opened. The same bee species recorded on the dune were also recorded at the botanical garden, suggesting that the artificial dune at the botanical garden offered suitable conditions for the natural pollinators of this endangered cactus.

Silene lemmonii S. Watson (Caryophyllaceae) is a tap-rooted herbaceous perennial that grows in montane habitats throughout California and Oregon. In 1999 and 2000, I studied the pollination biology and mating system of a single S. lemmonii population occurring near Dubakella Mountain in the Trinity National Forest, CA. Although S. lemmonii is self-compatible, individual flowers are strongly protandrous and fruit set rarely resulted from autogamy in both years of the study. Silene lemmonii flowers bloom at night, yet I observed no nocturnal insects visiting flowers in 1999 and visitation by diurnal bees and flies was infrequent during both years of the study. Despite the paucity of visitors, plants exhibited relatively high fruit set (x¯  =  40% in 1999 and x¯  =  61% in 2000). In 2000, I conducted an experiment to reconcile the occurrence of relatively high fruit set with rare insect visitation. I examined the contribution of insect visitation, autogamy, and jostling-induced geitonogamy (occurring when individual flowers on the same plant brush into one another) to fruit production. I found that fruit and seed production in S. lemmonii was primarily mediated by diurnal and nocturnal insect visits, but jostling-induced geitonogamy contributed to ∼20% of fruit set. To my knowledge, this is the first study to report jostling-induced geitonogamy and the first to describe the pollination biology of S. lemmonii.

We investigated patterns of infraspecific variation among populations of Pedicularis densiflora, including populations formerly recognized as P. densiflora subsp. aurantiaca. Several statistical analyses (UPGMA, ANOVA, and PCA) were conducted on floral traits measured in the field. All three statistical analyses indicated consistent differences in floral morphology among populations. These differences were confirmed by a review of over 1000 herbarium specimens. Two series of populations were separated, and two species recognized, Pedicularis aurantiaca and P. densiflora. Pedicularis aurantiaca had large calyces with floral tubes included at anthesis, reduced lower labia, and enlarged galea openings. Pedicularis densiflora had short calyces with fully exserted floral tubes, enlarged lower labia, and smaller galea openings. Taxonomy, phenology, and floral differences are discussed in the context of previously published data on pollinator visitation.

The history of the combination Plagiobothrys figuratus (Piper) I. M. Johnst. ex M. Peck is explained, and P. figuratus var. corallicarpus (Piper) K. L. Chambers is proposed to replace an earlier combination at the subspecific rank. In the Plagiobothrys scouleri (Hook. & Arn.) I. M. Johnst. complex, the following are recognized as separate species for treatment in the Oregon Flora Checklist: P. scouleri, P. reticulatus (Piper) I. M. Johnst., P. bracteatus (Howell) I. M. Johnst., and P. hispidulus (Greene) I. M. Johnst.. Plagiobothrys cusickii (Greene) I. M. Johnst. is made a synonym of the latter taxon. Lectotypes are provided for Allocarya bracteata Howell, A. cusickii var. vallicola Jeps., A. charaxata var. debilis Brand, A. commixta Brand, and A. piperi Brand.

The names Swertia recurva Sm. and Halenia recurva (Sm.) C.K. Allen are typified by a specimen of a species native to Colombia. The correct name for the western North American species that has been called H. recurva is H. rothrockii A. Gray.

Eremogone cliftonii is described as new from northern California. Petal and capsule lengths and presence or not of pubescence or a bloom on vegetative structures are features useful in distinguishing this novelty from E. aculeata and E. kingii var. glabrescens, the congeners found in the region. Eremogone cliftonii occurs in open or forested areas on decomposing granite.

Castilleja victoriae is described from the vicinity of southwestern Victoria, southern Vancouver Island, British Columbia, Canada and from San Juan Co., Washington, U.S.A. It is an annual member of subg. Colacus (Jeps.) T.I. Chuang & Heckard, sect. Oncorhynchus (Lehm.) T.I. Chuang & Heckard, formerly placed in the genus Orthocarpus Nutt. It is apparently most closely related to either Castilleja ambigua Hook. & Arn. or Castilleja tenuis (A. Heller) T.I. Chuang & Heckard. The new species differs primarily in its uniformly dull reddish-brown floral bracts and calyces, bicolored and unspotted corollas, and restrictive habitat requirements. Several historic populations are extirpated, and of the three extant populations only one consists of enough individuals in a protected location to be considered reasonably secure. We advocate additional surveys of its limited habitat and conservation measures to protect the species.

Pentachaeta aurea Nutt. subsp. allenii Keil is described as new. It is apparently endemic to southwestern Orange Co., California. Lamina tips of ray corollas of living specimens of the plants are pale yellow in early morning but turn brilliant white after 1–2 hr in sunshine; laminae of subsp. aurea are solid yellow.

Pentagramma triangularis (Kaulfuss) Yatskievych, Windham, & E. Wollenweber subsp. rebmanii Winner and M. G. Simpson subsp. nov. is a new subspecies endemic to south-central to southeast San Diego County, California, USA, and inland, northwestern Baja California, Mexico. It is uncommon on seasonally moist, granitic-derived or gabbro-clay substrates, distinguishable from other Pentagramma triangularis subspecies by the scattered white farina on the adaxial blade surface and lightly scattered along the stipe.