Winter Care of Garden Roses

Plant Disease
The Oregon State University affiliated author focuses the discussion on pest control in garden roses. Specifically addressed are symptoms and controls for "Black Spot", "Powdery Mildew", and "Rust". The three diseases are found on the leaves and new growth of the plants.

Bacterial Disease of Red Maples

Plant Disease
A report on the discovery of a bacterial leaf-spot, a species of Pseudomonas, on cuttings of two different Red maple varieties, 'October Glory' and 'Red Sunset'. The author discusses symptoms of the disease and possible control measures.

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'.

Simazine Injury on Maple and Other Shade Trees

Plant disorders
Veinal chlorosis in the leaf tips of maple and other shade trees was a persistent problem although it was notice some of the trees out grew the symptoms. Several Acer saccharinum cultivars were used in experiments testing the tolerance of the trees to the herbicide.

Evaluation of Compatible and Oregon Bartletts on Quince

A discussion involving the propagation of compatible pear rootstock, inter-stock and scions for production. Comparisons of the various varieties were based on overall tree size, compatibility, and yield per tree area for scion-rootstock combinations.

Phytophthora Crown Rot of Rock Daphne

Plant Disease
A warning to growers of rock daphne (Daphne cneorum) in 1976 after Phytophthora crown rot was detected in rock daphne production fields. Very little was know about the disease at the time but the authors reference a previously published report on Phytophthora as a general guide for growers.

Cylindrosporium Leaf Spot or Yellow Leaf on Cherry Cause: Cylindrosporium Padi, a Fungus

Plant Disease
A brief report on Cylindrosporium Padi, a serious fungal disease of cherry seedlings in nurseries. The Oregon State University affiliated author discusses symptoms of the disease, the timeline for leaf spot development, and causes of continued infection.

Rootstocks for Pear: Variability in Calleryana

The authors discuss the popular use of Pyrus calleryana as a pear rootstock. Pyrus calleryana did just as well if not better than Bartlett and Winter Nellis in Oregon State University studies. Included in the discussion are the issues growers were having with the rootstock and several possible solutions.

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).

Lophodermium Needle Cast

Plant Disease
Research was conducted to gain incite into the fungal disease, Lophodermium needle cast, affecting Scotch pines in the Pacific Northwest. The most susceptible species were considered to be Scotch pine (Pinus sylvestris), red pine (Pinus resinosa), and Monterey pine (Pinus radiata).