Dothiorella Canker of Crab Apple

Nursery Crops
A report of the author's observations concerning Dothiorella canker of crab apples, Botryosphaeria ribis. Symptoms of the fungus are discussed along with other plants the fungus was noticed to be affecting, control methods for the disease are also addressed.

Bacterial Gall Disease on Douglas Fir, Pseudotsuga taxifolia

Plant Disease
Research indicated the disease bacterial gall on Douglas fir was caused by an insect, Cooley's chermes (Chermes cooleyi Gill.). The author offers descriptions of the galls, where they form on the tree, the impact the galls have on trees, and how the insect transmits the disease.

Juniper Decline

Nursery Crops
Junipers were affected by what appeared to be a unknown root disease. Although it was thought to be Phytophthora, because it could not be verified the disease was referred to as "juniper decline". The Oregon State University affiliated authors discuss the disease, it's symptoms, and research being conducted on the subject.

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).

Bacterial Speck, a Leaf Spot on Tomato Can be a Serious Problem of Tomato Seedlings

Plant Disease
Tomato seedlings grown in greenhouses and garden centers were observed to be affected by bacterial speck , a leaf spot that could lead to defoliation and unsellable plants. The disease is caused by Pseudomonas tomato and was thought be carried on the seeds.

Brown Garden Snail

Nursery Crops
The topic discussed by the Oregon State University affiliated author is the brown garden snail and it's impact on the nursery industry. The issue of shipping and receiving plant material is addressed. Suggestions on how to control the snail and information on it's lifecycle are also included.

Hawthorn Leaf-Blight

Disease
Oregon State University affiliated author briefly discusses hawthorn leaf-blight, a common hawthorn disease, included are descriptions of the affected leaves, lifecycle, and control measures. The cause of the disease is Fabraea thuemenii, it leads to defoliation and possible death of the tree.

Distribution of SEEBB and DED in Oregon

Insects
Dutch elm disease, Ceratocystis ulmi, and it's principle vector the European elm bark beetle, Scolytus multistriatus, are traced from their arrival in the US to their detection in various Oregon counties. Detection methods are discussed along with anticipated increased efforts to slow the spread of Dutch elm disease.

Tent Caterpillar Alert

Insects
In the winter of 1975, shade and fruit tree growers were warned about possible tent caterpillar population increases during the up coming growing season. Oregon counties that experienced high populations during the previous population spike in 1965-66 were; Multnomah, Columbia, Washington, and Yamhill

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