Disease Control for Perennial Plants

Plant Disease
The Oregon State University affiliated author discusses implementing preventative disease control programs for a wide variety of perennial plants. A list is provided of the many different perennials grown in the pacific northwest and the diseases they are commonly associated with.

Leaf Browning and Shedding - Arbor-Vitae and Juniper

Plant disorders
Leaf browning and shedding in juniper and arborvitae are addressed in an effort to differentiate between natural causes and disease in the plants. The three fungi discussed can infect the plants and cause extensive damage, they are; leaf-blight (Didymascella thujina), tip-blight (Coryneum berckmannii) and juniper blight (Phomopsis juniperovora).

Douglas Fir Needle Cast

Plant Disease
A discussion of Douglas fir needle cast, caused by the fungus Rhabdocline pseudotsugae, as it was an increasing problem at the time this article was written. The author also discusses the fungus lifecycle, symptoms, control practices, and research being conducted on chemical controls.

Insect Problems on Narrow Leaf Evergreens

Insects
Several insect pests of narrow leaf evergreen trees are discussed in regard to hosts, lifecycle, the type of damage caused, and control methods for each of the pests. The insects addressed are; the Cooley Spruce Gall Aphid (Adelges cooleyi), pine needle scale (Phenacaspis pinifoliae) and the black pineleaf scale (Nuculaspis californica), and Douglas fir needle midge (Contarinia spp).

Status of the European Shoot Moth in Oregon

Insects
A brief history of the invasive pest European pine shoot moth, Rhyacionia buoliana (Schiff.), in Oregon. Surveyed Oregon counties found to have infestations were; Clackamas, Lane, Marion, Multnomah and Umatilla. Control methods for the moth are discussed along with descriptions of the life cycle and damage caused by the moths.

Pine Shoot Moth Control

Insects
Pesticides were tested over a period of four summers for improved control of European pine shoot moth. The author suggests several methods for predicting the first spray application date as it can vary from year to year.

Horticultural Crops Research Needed for the 1970's

Nursery Crops
Based on a previous article calling for research in the ornamental crops industry in Oregon, the authors elaborate on what ornamental and horticultural areas need more research. Specific crops are listed along with the most pertinent areas for each crop needing more research.

Research Needs Discussed for Expanding Ornamentals Industry

Nursery Crops
The future of research and extension work in the ornamental industry at Oregon State University is discussed by the author. Research and extension staff worked to identify areas in need of research and established priorities with in those areas.

Control Juniper Webworm

Insects
Juniper webworm made its appearance in Oregon as a pest to ornamental and nursery plantings of juniper in 1951. The author describes how to identify and treat webworms on common juniper, Irish juniper, spiny Greek juniper and red cedar.

Nursery Buying Habits Surveyed

Nursery
The results of a 1958 marketing survey to determine the nursery buying habits of homeowners in the Portland, OR area. The survey included questions about the influence of home value, age, length of residence, and family income on buying habits.

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