Marah oreganus, a perennial, belongs to the Cucurbitaceae family
and it is commonly known as wild cucumber. In the past, this plant
grew along fence rows, but now wild cucumber has become a weed
problem in perennial grass seed fields of western Oregon. Several
research studies were conducted to examine...
The genus Lopidea Uhler is revised for America north of
Mexico. The relationship of Lopidea to other orthotyline
genera is discussed and it is proposed that the genus
Ilnacora Reuter is the sister group of Lopidea.
Forty-eight species of Lopidea are recognized in North
America, one of which is described...
There are several grape disorders that reduce fruit
set. One, millerandage, is from poor fertilization to
produce "hen and chicken" or small seedless berries; while
another, Coulure, is the failure of grape flowers to
develop into berries. A third one, inflorescence necrosis
(INec), is a disorder that should be in...
Herbicides were tested for the selective control of bentgrass in
Kentucky bluegrass turf under three levels of competition. Best control
in zero competition was obtained with a winter treatment of
bromacil at two pounds per acre. Under circumferential and direct
competition, best control was obtained with a summer and fall...
In the Pajaro Valley near Watsonville, California,
twospotted spider mite (Tetranychus urticae Koch)
populations were surveyed in 1983 and '84 to detect the
influence of immigrants from nursery plants or
surrounding vegetation on subsequent resistance
development to cyhexatin and formetanate in strawberry
fields. Susceptible mites (cyhexatin LC50 = 0.0039 %...
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...
This thesis consists of four chapters. Literature is
reviewed in Chapter 1. Chapter 2 describes an addition
series experiment to determine the influence of species
density and proportion on vegetative and reproductive yield
of spring wheat and Lolium multiflorum. Chapter 3 consists
of a growth analysis experiment to determine whether...
Salmonberry (Rubus spectabilis) and thimbleberry
(Rubus parviflorus) are clonal shrub species common to
reforestation sites in the Oregon Coast Range. These
species have economic importance, because they reduce
conifer seedling growth and survival. A population modeling
approach was used to facilitate study of the biology of
these species and to...