The Chemical Basis for Resistance of Certain Rhododendron Cultivars to Foliar Feeding by Root Weevils

Breeding and Selection
Studies were conducted to determine if there was foliar feeding resistance to root weevils in certain rhododendron cultivars. The results, suggesting the lepidote branch had more resistant cultivars than the azalea branch, are thoroughly discussed by the author.

A Root Weevil Perspective

Root weevils can be a serious pest for Oregon growers of ornamental plants, the root weevil feeds on more than 100 plant species. The author offers a brief but informative discussion on the life cycle, root and foliar feeding, control of adult root weevil, and larval control.

Apple Maggot (Rhagoletis pomonella)

The apple maggot was detected on a homeowner's tree in the Portland, OR area in the late summer of 1979 and was again detected on other noncommercial plantings the following year. Apple maggot hosts, damage, detection and control are addressed by the author.

Weed Control in Nurseries and Ornamental Plantings

A partial list of herbicides for perennial weed control intended for nurseries and ornamental plantings. The author addresses correct weed identification, weeds controlled and not controlled by the herbicides, terms used in weed control, and application methods.

Gypsy Moth in Washington

The gypsy moth was detected in the Seattle, WA area in 1977 using pheromone (female sex scent) traps. The author discusses the gypsy moth in regard to; local history, the problem involving gypsy moths, eradication efforts, and the efforts nurseries could make.

Gypsy Moth in Oregon

Gypsy moth, Porthetria dispar, the invasive pest of trees and shrubs was trapped for the first time in Oregon in the summer of 1979. The author discusses the moth's lifecycle, history in the US, efforts made to educate the public, and the plan for the following year.

Germination Requirements for Acer Macrophyllum, Bigleaf Maple

As the use of native plants in landscaping became more popular, the authors recognized the need for more information on the collection, handling, and cultural requirements the plants. The discussion focuses on the information collected regarding the Bigleaf Maple.

Factors to Consider Before Tank Mixing Pesticides

The dangers of tank mixing pesticides are addressed by the University of California affiliated author. The factors discussed include; chemical incompatibilities, physical incompatibilities, general principles for mixing pesticides, specific mixtures to avoid, and causes of phytotoxicity.

Progress in Tissue Culture Propagation of Ornamentals

Plant propagation
Research was conducted on the propagation of rhododendron, apples, raspberries, strawberries, lily bulbs, iris bulbs, Kalmia, Daphne, and arctostaphylos by tissue culture at the Northwestern Washington Research and Extension Unit.

Defoliation by Winter Moth - A Pest New to the Pacific Northwest

A discussion about the history and discovery of the winter moth, Operophtera brumata, in Oregon State University and Oregon Department of Agriculture Entomology collections taken from the Portland, OR area. Appearance, damage, and life history are addressed.