This research examined the biology of barb goatgrass (Aegilops triuncialis L.) a weedy annual grass that is invading the rangelands of California. Germination and root growth characteristics of barb goatgrass were compared to soft chess (Bromis mollis L.), medusahead rye (Taeniatherum caput-medusae (L.) Nevski), slender wild oats (Avena barbata L.),...
A living mulch system consists of growing a regulated cover crop
with an economic crop. Living mulches are often interplanted with
horticultural crops, but competition for water can adversely affect
crop production. Various management practices may limit the negative
effects.
Studies were conducted for two purposes: (1) to determine if...
The effects of five tillage treatments on soil bulk density and
mechanical impedance were examined on Newburg sandy loam soil in the
Willamette Valley, Oregon, in 1987. Subsequent effects on seedling
emergence and yield of carrots (Daucus carota L., cvs. Orlando Gold
and Royal Chantenay) were also measured. Mechanical impedance...
The Mark 0. Hatfield Marine Science Center (HMSC)
public education opportunities include interpretive programs
offered along the Estuary Nature Trail. The purpose of this
study was to determine the effectiveness of three informal
education programs, interpretive signs, a self-guided trail
brochure, and guided naturalist walks, in imparting
information on the...
Field, screenhouse, and laboratory experiments were conducted to
study weed interference in rice grown on hydromorphic soils at the
International Institute of Tropical Agriculture (IITA) at Ibadan, Nigeria.
Rice and weeds emerged at the same time, 1 week after planting.
Weed dry weight was significantly reduced when the crop was...
California brome (Bromus carinatus Hook & Arn), is
considered an important weed infesting wheat and grass seed
fields in the Willamette Valley of Oregon. Field and
greenhouse experiments were conducted to study some
biological aspects to develop more efficient management
strategies.
A field experiment was conducted to determine the
effect...
The interference of barnyardgrass (Echinochloa crusgalli),
pigweed (Amaranthus retroflexus),downy brome (Bromus
tectorum),and tumble mustard (Sisymbrium altissimum)
with alfalfa was studied. Alfalfa was seeded with each of
the four weeds on August 14 and September 15, 1981, and on
April 13, 1982. Alfalfa also was seeded on August 27, 1981,
with...
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...