The primary intent of this study was to clarify the role of the
endophyte in the Ceanothus symbiosis.
A technique utilizing a 20 percent solution of H₂O₂ was developed
which allowed the isolation of a Streptomyces sp. from the root
nodules of some Ceanothus species. Further characterization suggested
Six, recent clear cut areas were selected in the Douglas-fir
zone of the Western Cascade Range of Oregon to determine the
environmental and nutritional effects that snowbrush has on the establishment
and growth of Douglas-fir seedlings.
One thousand eighty milacre sample plots on the six clear cuts
were used to...
Frankia from root nodules of nine different species of Ceanothus were
characterized. DNA was amplified directly from nodular material using the polymerase
chain reaction (PCR). The amplified region includes the 3' end of the 16S rRNA gene,
the intergenic spacer (IGS), and a large portion of the 23S rRNA gene....
The ecological and silvicultural importance of snowbrush,
Ceanothus velutinus, in the areas west of the summit of the Oregon
Cascades was studied. Particular attention has been given its nitrogen-
fixing ability under both field and greenhouse conditions.
On west slopes of the Oregon Cascades snowbrush occurs above
2, 500 feet...
The evolutionary relationship between Frankia and actinorhizal plants was evaluated
by reconstructing molecular phylogenetic trees from nifH, 16S rDNA, and rbcL
nucleotide sequences. Subgroupings in Frankia phylogenetic trees reconstructed from
nifH and from 16S rDNA sequences were consistent in terms of plant origins of Frankia
strains. Although the branching order...
Two case studies of 5 ecosystems were used to examine the nitrogen fixation rate of red alder (Alnus rubra Bong.), varnishleaf (Ceanothus velutinus var. laevigatus (Hook.) T. & G.), deerbrush (C. i ntegerrimus H. & A.), and snowbrush (C. velutinus var. velutinus Dougl. Ex Hook). The first case study assayed...