Pear Trellis Rust Under Control in British Columbia Mainland

Plant Disease
A survey and eradication program was put into place after pear trellis rust (Gymnosporangium fuscum), was found in the Frasier Valley, British Columbia in 1972. A pear and juniper quarantine was imposed in the area in an effort to gain control of the disease.

The Influence of Stress on Diseases of Nursery and Landscape Plants

Plant Stress
A discussion of the influence stress can have on diseases of nursery and landscape plants. The author addresses the increased susceptibility to disease when plants are weakened by stress, drought or water stress, excess water stress, and high and low temperature stress.

Bark and Sawdust - Mulches in Maintenance Planning

Soil media
Using mulches in landscaping and gardening environments is the topic discussed by the author. Specific areas addressed are; types of mulch, effect of mulch on microclimate, effect of mulch on soil conditions, and problems in mulch selection.

Special: Plant Injury Caused by Sawdust and Barks

Media
The use of sawdusts and barks in media mixes and mulches is addressed by the Oregon State University affiliated author. The results of tests conducted to test the phytotoxic effects of two species of fresh bark are discussed along with recommendations.

Avoiding Pesticide Phytotoxicity

Plant disorders
The University of Florida affiliated author addresses how to avoid pesticide phytotoxicity in ornamental plants. The five most common types of phytotoxicity identified are; burn, necrosis, chlorosis, leaf distortion, and stunting or abnormal growth.

Update: The Black Vine Weevil Plague

Insects
Concern was growing about increasing Black Vine weevil populations in the winter of 1976-77. Part of the reason for concern over the weevil infestation was the lack of approved pesticides for the weevil. The authors discuss possible control methods and encouraged growers to learn about the Black Vine weevil.

Irrigation and Oregon Water Laws

Water
Water availability for the upcoming growing season was a concern due to an unusually dry winter. The author discusses the legalities of Oregon water rights regarding greenhouse and nursery crops. Several different types of irrigation permits are addressed along with where to obtain them.

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.

Six Dwarf Mugo-Pine Cultivars Released

Breeding and Selection
After years of research conducted on Mugo or Swiss Mountain pine, a popular dwarfing shrub used in landscaping, six cultivars were selected to be released to the nursery trade. The selected cultivars were; OSU 67-2, 'Oregon Jade', OSU 67-5, 'Alpenglow', OSU 67-9, 'Elfengren', 67-15, 'Oregon Pixie', OSU 67-20, 'Tyrol', and OSU 69-2, 'Green Candle'.

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).

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