Studies were conducted to determine the extent and nature of
sub-lethal effects of herbicides on plant growth. At least one
herbicide from each major chemical class of herbicides was evaluated
under greenhouse conditions. Oat plants were grown in sand
culture to eliminate soil interferences. Herbicides were applied
pre-emergence in nutrient...
This study was designed to learn the effect a specific herbicide practice on plant communities. Data were obtained from brushfields that had been aerially sprayed with 2,4-D (2,4 dichiorophenoxyacetic acid) and/or 2,4,5-T (2,4,5 trichlorophenoxyacetic acid). Qualitative data on species composition, cover percent, height, response to herbicide and site description were...
Alnus rubra (Bong. ) seedlings were grown in sand culture and
irrigated with nutrient solution containing CdCl₂
ranging from 5 μg to 100 mg per liter. Treatment of A. rubra seedlings for 4 weeks
with 50 and 100 mg CdCl₂
per liter of nitrogen-free nutrient solution
decreased in situ nitrogenase...
The effect of nitrogen (N) application on seed yield of Limnanthes
alba was studied for two years at two locations. Seeding following alfalfa
(Medicago sativa L.) was compared to establishment after wheat
(Triticum aestivum L.). Treatments used were a control (no N applied),
and two rates of N (50 and...
Pastures consisting of mixtures of subclover (Trifolium
subterraneum) and grasses have responded to sulfur fertilization
on many sites in Douglas County, Oregon. The objectives of this
study were to examine specific changes in forage quality which occur
as sulfur is applied in excess of the amount required for maximum
yield...
A nutrient solution technique developed for wheat was used to
determine tolerance of rice cultivars to aluminum (Al) toxicity.
Pre-germinated rice seed was placed on top of a screen and allowed
to grow on the Al-free solution for 72-96 hours or until the primary
root was 2-3 cms long. Seedlings...
The herbicide rate required to reduce growth by 50% (GR₅₀) of 11
cultivars of red fesue (Festuca rubra L. and F. rubra ssp. commutata)
and for four cultivars of bentgrass (Agrostis tenuis Sibth. and A.
stolonifera L. var. palustris) to sethoxydim (2-[1-(ethoxyimino)
butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one) was
determined in greenhouse and laboratory experiments....
Nitrate reductase is known to be the enzyme regulating the
reduction of nitrate to nitrite in plants. This reduction is the first
and rate-limiting step in the transformation of inorganic nitrate to
a cellular nitrogen form. Since this reduction process is essential
to phytoplankton growth when nitrate is the only...
The effects of light incident on leafy cuttings is
quite complex because' light influences several factors
which may affect root formation. One effect of light is
to influence the carbohydrate status of the cutting by
influencing photosynthesis. The role of current photosynthate
in the rooting of leafy cuttings is uncertain....
Herbicides are being used as a tool by forest managers to speed
the restocking of sites where tree seedlings face competition from
grasses for limited moisture, light and nutrients. Retarded growth
or, more commonly, death of the seedlings would occur if a selective
herbicide was not used to control competing...
The tolerance of woody plants to picloram (4amino-3,5,6-trichloropicolinic acid) has been shown by field applications to vary from mild to extreme. A laboratory study was done to investigate the basic causes for this range of tolerance known to exist among three woody plant species, Fraxinus pennsylvanics, March, (green ash) resistant,...
Spectroradiometric analyses were made to examine the light filtering capacity of coniferous forests and to establish the lower light energy limits for growth of Pseudotsuga menziesii (Mirb. ) Franco, Abies concolor (Gord. and Glend.) Lindi. and Pinus ponderosa Dougi. Visible energy(400-750 nm) was recorded at 48 points under four mixed...
Published October 1967. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
An investigation was undertaken to determine whether
potassium is indeed necessary for the in vivo synthesis of a
specific protein. The effects of univalent cations on the
inductive formation of nitrate reductase and on the level of
activity of representative non-adaptive enzyme are presented.
Cultures of Neurospora crassa were grown...
Three greenhouse experiments were designed to measure the
effects of N, K and Cl on the nutrient uptake by Russet Burbank potatoes
(Solanum tuberosum). A Deschutes sandy loam soil from Powell
Butte area in Central Oregon, low in potassium, was used to study
these effects.
Nitrogen applications produced significant increases...