Optimal floral display (the number of simultaneously open flowers) is frequently viewed as a balance between pollinator attraction and avoidance of pollinator-mediated interfloral selfing (geitonogamy). However, the most beneficial display size may be affected by pollinator abundance, pollinator identity, and other environmental variables. We determined the effects of individual floral display and patch size on pollination outcomes in natural populations of a mixed-mating annual plant, Clarkia concinna (Fischer & C.Meyer) E.Greene. We predicted that individual plants with larger floral displays would have both greater pollinator visitation and more geitonogamy. Additionally, we tested whether the effects of floral display would be greater in smaller patches of plants. Larger individual floral displays increased total geitonogamy, but the effect of display on geitonogamy differed among pollinator taxa. Visitation rates were lower in small patches for some pollinators. However, individual display size did not affect per flower visitation rate in small or large patches. Therefore, if we only consider the expected tradeoff between pollinator attraction and geitonogamy, the number of simultaneously open flowers appears excessive. In this species, large floral display size requires explanations beyond increased pollinator attraction, such as temporal constraints on flowering imposed by a limited growing season and the benefits of additional low-quality offspring.

On Quercus agrifolia Née, Fagaceae, (Coast Live Oak) trees in California, small clusters of branched trichomes on the abaxial leaf surface serve as domatia, protective structures for mites. These structures are a distinguishing characteristic of Q. agrifolia and we hypothesize may be shaped by natural selection. Here we test the first two of three prerequisites for adaptation via natural selection: (1) the trait must vary among individuals, and (2) the trait must be heritable. Trait variance across 20 trees in a natural stand was assessed by collecting 20 leaves per tree and determining the proportion of leaf vein axils with domatia. From the same trees, acorns were collected, germinated, and the proportion of leaf vein axils with domatia was recorded for 12- and 18-mon-old saplings. Heritability was then assessed by comparing the resemblance between maternal trees and offspring. We find that both prerequisites are met: maternal trees exhibit substantial variation in the proportion of leaf vein axils with domatia, ranging from an average of 0–0.85 per leaf, and heritability estimates for 12- and 18-mon-old saplings were 0.33 ± 0.10 SD and 0.53 ± 0.10 SD respectively. A follow up study is needed to assess the third prerequisite for adaptation via natural selection, that survival and reproduction of oaks varies based on the proportion of leaf vein axils with domatia. We hope future researchers will pursue this line of study.

Human disturbance is often associated with a decline in the abundance of native understory species such as Trillium ovatum Pursh (Melanthiaceae); a species that has been used as an indicator of forest health and recovery following timber harvest. The relationship between this species and the moderate levels of disturbance created by recreational trail use, however, is not clearly understood. This perennial herb was studied in three California State Parks utilizing fifty-eight 10 m randomly-located transects, placed perpendicular to hiking trails and divided into ten sequential 1-m sample plots. Occurrence and abundance of T. ovatum were analyzed with regard to proximity of trails and a suite of abiotic and biotic variables. Results indicated a higher abundance of T. ovatum near hiking trails, with a negative correlation to the distance from those trails. Other abiotic variables associated with T. ovatum included a positive correlation with slope and negative correlations with elevation and distance to the nearest stream. Positive associations were also detected between T. ovatum and canopy cover, the canopy dominance of Sequoia sempervirens (D.Don) Endl., and the abundance of several other native understory species. These findings underscored the nuanced relationships between T. ovatum and different levels of anthropogenic disturbance.

During recent work on the systematics and phylogenetics of the new liverwort genus Calasterella (Aytoniaceae), the need became clear for typifying its type species Calasterella californica (basionym Fimbraria californica Hampe ex Austin). This species is the current subject of detailed genetic studies of its population structure, which may result in the description of cryptic diversity, necessitating a clear understanding of where the name C. californica applies. We implement a two-step lectotypification, first clarifying the lectotype designation made by Evans, and then we designate as epitype a recently collected specimen from the San Francisco, California region.

I report the discovery of a population of Jeffrey Pine (Pinus jeffreyi A.Murray bis & al., Pinaceae) in the southern Sierra Nevada that is notably higher than any other reported Jeffrey Pine population. The individuals encountered were found on the south slopes of Mt. Kaweah, at elevations between 3600 m and 3858 m. The individuals at 3858 m were 567 m higher than the highest collection found in the CCH1 database and 758 m higher than the high end of Jeffrey Pine distribution indicated in the Jepson eFlora. Extraordinarily, the Jeffrey Pines found at 3858 m appear to be the highest trees on Mt. Kaweah, higher even than Lodgepole Pine (Pinus contorta subsp. murrayana [A.Murray bis & al.] A.E.Murray) or Foxtail Pine (Pinus balfouriana A.Murray bis & al. ssp. austrina R.J.Mastrog. & J.D.Mastrog.) and may be the highest recorded trees in California to date. This was an exploratory study, but the age structure of the population, the non-reproductive status of all sampled trees, the locations of the trees, the commonly dead upper branches on larger individuals, and the dispersal ecology of the species all provide clues as to the population's provenance and its future. Preliminary consideration of my findings suggests the possibility that Jeffrey Pine is being leapfrogged over more typical tree line species by bird dispersal, and the population may be slowly moving uphill as seed caching by birds encounters a gradually rising “window of environmental opportunity” for germination and seedling survival. Further inventory of high elevation areas in the southern Sierra Nevada is needed, as is further study of the factors that may be driving this interesting phenomenon.