The goal of the study was to collect data on the ecology and
reproduction of Sophora leachiana in order to help explain the rarity
and restricted range of this species. There are 13 known populations
of S. leachiana, occurring in a 29 by 6.4 km area in the Siskiyou
Mountains...
A systematic study was made of the species comprising
Phacelia section Miltitzia. These species, which are commonly
found in the Great Basin physiographic province of western North
America, are distinguished from other members of Phacelia by their
yellow, marcescent corollas and their transversely corrugated seeds.
This project utilized morphological, cytological,...
The Mimulus washingtonensis complex is a group of morphologically similar
species centered in the Pacific Northwest. All are rare, and most are under
consideration for listing as endangered. Morphometric and pollination data were
used in developing a revised taxonomy for the group. Five species and two varieties
are recognized. Mimulus...
Comparative morphological and anatomical studies of the dispersal mechanisms
characterizing the wheat complex (Triticum L. and Aegilops L.) have documented
patterns of adaptive radiation which may have significance for evolutionary
relationships. These patterns, which form an array of diverse types of diaspores
among the diploid taxa, appear conceptually to have...
Meiotic chromosome counts from 200 populations of Claytonia
(Montia) perfoliata (sensu lato) reveal a polyploid pillar complex based
on three morphologically different, chemically distinct, and geographically
defined diploids. The basic chromosome number is x=6.
Diploid C. perfoliata Willdenow with linear juvenile leaves and deltoid
mature basal leaves ranges southeastward from...
A cytogeographical study was made of populations of tetraploid
(n=18) and hexaploid (n=27) Achillea millefolium (Compositae-
Anthemideae) from the Pacific Coast states. There is a complex
distributional pattern, involving overlapping ranges, mixed populations,
migration of one form into areas occuplied by the other,
pentaploid hybrids, and septaploid and octoploid plants....
This work was performed on Trillium albidum Freeman (Liliaceae), to
clarify the pattern of morphological variation between the small-flowered
populations at the northern limit of its range ( T. parviflorum Soukup) and the
larger-flowered populations from southern Oregon and northern California. It was
hypothesized that only a single species of...
Microseris laciniata is a perennial, self-incompatible
species classified in subgenus Scorzonella. It is
morphologically the least specialized species in the genus,
in contrast to the members of subgenus Microseris, which
are morphologically advanced, self-compatible annuals.
First-generation hybrids were available from crosses
involving eight populations of two subspecies of Microseris
laciniata...
Arctostaphylos viscida Parry and A. canescens Eastw.,
two well-known and frequently encountered manzanitas in the
Siskiyou Mountains in southwestern Oregon, are shown to
hybridize and to produce an extensive series of morphological
intermediates. The hybridization occurs wherever populations
of these two species meet at contact zones of
serpentine and non-serpentine...