From each population we collected fully expanded leaves from 19 mature Dirca palustris selected to represent the spatial distribution of plants within the population.
Floral and vegetative traits differed among the populations of Dirca palustris, with the populations in Florida and North Dakota the most phenotypically distinct (Table 2).
Regarding precipitation, it may be that the specific habitats in which Dirca palustris occurs are similar in soil moisture despite differences in precipitation on the regional level, so interpretation of this correlation is difficult.
Our genetic results also provide insight on the phylogeography and conservation value of the populations of Dirca palustris we studied.
Populations like the one in North Dakota, which may both lack genetic diversity and be most adapted to conditions at the leading edge of range shifts as a consequence of directional selection during migration to new climates (Lacy, 1987), could be important for northward expansion of Dirca palustris in response to regional climate change (Davis and Shaw, 2001).
Leatherwood in Kansas: A morphological assessment of an anomalous population of Dirca palustris (Thymelaeaceae) [Abstract].
1 is an overall, radial longitudinal view of a water-conducting cell or vessel member in the wood of Dirca palustris. The large opening at the top, known as a perforation, is actually located on the inclined end wall of the cell.
5), and for the most part, Dirca palustris does not, although sometimes very small amounts of vesturing (best described as obscure) can be observed (Fig.
Taxon Herbarium or City Date of Collection Pimelea arenaria (1) AUA 11 Oct 1979 (2) AUA 22 Dec 1979 Pimelea prostrata AUA 26 Jan 1980 Dirca palustris (1) AUA 27 Mar 1969 (2) AUA 27 Mar 1969 (3) AUA 19 Mar 1989 Gnidia caffra (1) AUA Jan 2000 (2) AUA Jan 2000 Daphne gnidiodes K 26 Jul 1960 Taxon Collector(s) No.