HOE 23408 [ 4-(2' , 4'-dichlorophenoxy)-phenoxy-u-propionic
methylester.1 is a promising new compound for control of wild oats
and other grass weeds in small grains. Several factors influencing
its use for this purpose were investigated.
Greenhouse bioassay studies were conducted in 1975 to determine
relative persistence of HOE 23408 in four...
Availability of evergreen forage plants during the
two dry seasons in arid central Somalia is very important.
Cordeauxia edulis is a multistemmed evergreen legume shrub
which grows in Central Somalia in plant communities
dominated by deciduous shrubs. There are two growth forms
of this plant. A form with small leaflets...
The response to glyphosate [N-(phosphonomethyl) glycine] of two
dodder species Cuscuta campestris Yuncker (field dodder) and Cuscuta
indecora Chiosy (largeseed dodder) parasitizing alfalfa (Medicago
sativa L.) was compared. In the absence of glyphosate, alfalfa was
killed or severely injured by parasitism from uncontrolled dodder.
Results of field experiments in which...
Extensive morphological and growth habit variations have been
reported for bitterbrush (Purshia tridentata), a widespread western
shrub frequently used in range revegetation projects. Hybridization
of this species occurs with cliffrose (Cowania stansburiana) at the
point of their overlapping range in Utah and is believed to be
responsible for expression of...
C-methyltransferase
(HIOMT) in chinook salmon (Oncorhynchus
tshawytscha). Various body tissues, as well as several
morphological brain divisions were tested for the presence
of HIOMT. Activity was found in the retina, the dorsal
portion of the diencephalon, and in the pineal gland of
chinook. However, the activity was significantly higher
in...
The black grass bug genus Irbisia Reuter was revised. Over 18,000
specimens were examined and information concerning the biology, host
plant and distributional relationships of the species was compiled.
In addition to external characters, the male claspers and vesica, and
the female dorsal libiate plate of the bursa copulatrix and...
Paraquat (1,11-dimethy1-4,4'-bipyridinium ion) and glyphosate [N (phosphonomethyl)glycine] are herbicides utilized for chemical seedbed preparation in the establishment of grass and legume seed crops. When these herbicides are applied after seeding the crop, seeds which are not protected by a layer of soil could be exposed to the herbicide. Effects of...
The Nearctic species of the genus Sympherobius
Banks are revised. Seventeen species are recorded from
the region. Two new species, S. constrictus and S.
quadricuspis are described from California and Arizona
respectively. Four new specific synonyms are proposed
(junior synonym(s) first): S. brunneus Nakahara and S.
stangei Nakahara = S....
Some perennial grass seed crops such as red fescue (Festuca rubra
L.) do not produce a profitable seed crop during the first growing
season. The present establishment method in Oregon for red fescue seed
crops generally entails spring planting which does not satisfy
vernalization requirements for seed production in the...
The North American species of the shore fly genus Notiphila Fallen were taxonomically revised. Over 13,000 specimens were examined from throughout the Nearctic Region and information relating to the biology of many species occurring in the West was gathered from both field and laboratory studies. Previously used characters were reevaluated;...
The genus Deraeocoris Kirschbaum of western America north of
Mexico was revised. Approximately 10,000 specimens from the Nearctic
Region were examined. Taxonomic characters used by previous authors
were reevaluated. In addition to the male parameres, the male vesica
and the female posterior wall of the bursa copulatrix and sclerotized
rings...
In an effort to describe the plant communities and
succession of the Oregon coastal grasslands, vegetation
and environmental data were collected from 75 stands at
24 separate locations ranging from Cape Falcon in Tillamook
County to Cape Ferrelo in Curry County. The vegetation
data consisted of cover and frequency values...
The western Nearctic species of the genus Phytocoris Fallen were
taxonomically revised. Over 15,000 specimens were examined.
Information concerning host plant associations and distributions was
compiled and summarized for use by future researchers. External
morphological features and characters of the male genitalia were used
to distinguish species. The genital tubercles...
A systematic study of the subfamily Dicyphinae Reuter (Heteroptera: Hiridae) resulted in a redefinition of the subfamily and included genera) and a revision of the
genus Dicyphus Fieber in the Western Hemisphere. The study entailed examination of about 14,000 specimens, including numerous noudicyphine, cimicomorphan taxa to assess character transformations. New...
Field studies were conducted in 1973 and 1974 to determine the
soil persistence of the herbicide M-3785 (containing 0.5 lb a.e.
Dowco 290 + 2.0 lb a.e. 214D/gallon). under cropping situations.
Spring barley (Hordeum distichon L. 'Hannchen') was grown at
Corvallis, Oregon and winter wheat (Triticum aestivum L. 'Nugaines.')
was...
Setaria lutescens (yellow foxtail) plants, grown from five seed
sources were compared in California. Seed sources were: Connecticut,
Iowa, Massachusetts, Pennsylvania and California. Morphological
and physiological differences between biotypes include: plant
size, growth habit, time required to mature and reproductive capa
city. Most significant is the prostrate habit of the...
Grassy balds are meadows that occur on or near the summits of montane peaks and ridges. The sites on which balds are located generally fall within the climatic tolerance ranges of associated tree species. This study evaluates the stability of a forest-meadow transition zone of such a bald on Marys...
Hard Fescue (Festuca longifolia Thuill.) has potential for in
creased turf use but does not respond well to normal seed production
management practices in Oregon. Field burning (the normal residue
management practice) results in reduced seed yields in commercial hard
fescue seed production fields but stimulates seed production in Chewings...
Field studies were started at Hyslop Farm, Corvallis,
Oregon in 1984 to determine the soil persistence of the
herbicide clopyralid (3,6-dichloropicolinic acid) under
cropping situations. The herbicide was sprayed on bare soil
at the proposed use rate of 0.14 kg/ha in the spring and on
the same plots at a...
Populations of an unknown species of Mimulus, herein
described as Mimulus hymenophyllus Meinke, were located
and studied near Horse Creek, a tributary of the Snake
River in eastern Wallowa County, Oregon. The new species
is differentiated from its apparent closest relative,
Mimulus jungermannioides Suksd., by an annual habit, long
petioles,...
Chromosome counts were determined for 152 accessions of Pseudoroegneria
spicata (Pursh) A. Löve and, combined with existing count
data, used to plot the distribution of diploid and tetraploid populations.
Morphological variation of 55 characters was examined in five
groups totaling 205 operational taxonomic units (OTU's), using
cluster, principal factor, and...
There is an increasing need for development of laboratory
identification procedures for purposes of plant variety protection, seed certification, quality control and consumer protection. In the past there were fewer commercial varieties and field
testing methods based on morphological differences were used satisfactorily. These tests require several months to complete...
This study was undertaken to obtain information on the quality of grass seed when windrowed at the high moisture levels necessary for obtaining maximum yields. A secondary goal was to monitor moisture and temperature fluctuations in the windrow and to relate their effects to development and deterioration of the seed....
Parents and progeny populations from a cross of 'Stephens'x 'Tibet dwarf' were grown in a spaced-planted experiment to obtain information concerning the nature of inheritance and possible associations between grain yield and the components of yield. Agronomic traits measured on an individual plant basis were: heading date, days to maturity,...
Orchardgrass and tall fescue seed crops are commonly springplanted
in Oregon, but do not produce a marketable crop during the first
growing season. Establishing orchardgrass and tall fescue with cereal
companion crops would provide income during the seeding year and could
increase seed production profits. This study was conducted to...
Two diverse genotypes of tall fescue, Festuca arundinacea Schreb (6X=42), with normal fertility, produced upon intercrossing, vigorous F
₁
hybrid plants that were sterile. One parent genotype (P₁)
was from P. I. 234-906, introduced from Switzerland and the other
(P₉) was an introduction from Turkey, P. I. 174-209. P₁
and...
Chloroplast DNA (cpDNA) variability and phylogeny were
studied via analysis of restriction site mutations and DNA
sequencing in a complex of three closely related species of
pines: Pinus radiata D. Don, P. attenuata Lemm., and
muricata D. Don. Genomic DNA from 384 trees representing
20 populations in the complex were...
The tracheal mite, Acarapis woodi (Rennie), parasitizes the
honey bee, Apis mellifera L., an insect used extensively by humans
for pollination of domestic crops and for bee products, primarily
honey.
This parasite was first discovered in 1921 on the Isle of
Wight, a small island situated in the English Channel...