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January 1, 1965
Following the success of a previous study to propagation Old Home pear (Pyrus communis) cuttings, experiments were conducted on several other Pyrus species. Two different propagations methods were tested on the various Pyrus cuttings.
September 1, 2008
Rhododendron (Rhododendron ‘H-1 P.J.M.’) and azalea (Rhododendron ‘Cannon’s Double’) were grown with (+N) or without (N-deficient) nitrogen (N) from May to September to determine the effects of N-availability on uptake, demand, and allocation of other mineral nutrients.
December 1, 1977
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.
June 1, 1965
Materials were tested to determine a suitable control for crown gall and black mold. The various materials were tested on Mazzard cherry seedlings after they were dipped in Agrobacterium tumefaciens.
November 1, 1978
A discussion about English holly regarding fertilization suggestions made by A.N. Roberts and R.L. Ticknor in their previously published paper on commercial production of English holly in the Pacific Northwest. The author discusses the recommendations made by Roberts and Ticknor.
December 1, 1966
An Oregon State University affiliated study was conducted on pears to determine the compatibility of pear on hawthorn (Crataegus oxyacantha) and mountain ash (Sorbus aucuparia). The study used several different scions and was designed to find new dwarfing pear stocks.
July 1, 1979
Foliar fertilization trials were conducted on tulips, Iris, and Narcissus to determine the effectiveness of a foliar fertilization spray on the bulb yields. The authors discuss their methods, materials used, and the results of the trial.
June 1, 1970
Research was carried out on nursery weed control with the use of herbicides. The herbicides were rated according to effectiveness of weed control and amount of plant damage. The weed control tests were conducted on both summer and winter weeds.
March 1, 1980
Botrytis blight, a plant disease caused by Botrytis cinerea Pers. ex Fr., on statice (Limonium sinuatum Mill,) was studied by the University of Florida. The following topics are discussed; symptoms, seeds, field planting, and cultural and chemical control.
December 1, 1971
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.
August 1, 1957
A study conducted on the correlation between gladiolus corm size post harvest and flower and leaf removal is discussed by the author. The information is especially pertinent for the commercial cut flower market but useful for the home gardener also.
May 1, 1981
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.
May 1, 1958
The topic of root anchorage and/or breakage in very dwarf apple trees is briefly discussed in regard to rootstocks and scions.
September 1, 1981
The use of growth regulators in the greenhouse or nursery to chemically prune plants was studied, specifically Atrinal applied to Photinia x fraseri, in an effort to determine the effect on branching habit and height of the plant. The methods and results are discussed.
December 1, 1975
The lifecycle of conifer needle rusts and their association with the Christmas tree industry are discussed by the Oregon State University affiliated authors. A table is provided of the most common needle rusts found in Oregon, the table includes the needle rust's hosts, and alternative hosts.
March 1, 1959
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.
November 1, 1981
Increased damage by Pseudomonas syringae, a bacterial disease, was noticed on a variety of nursery-grown shade trees. Research was conducted to determine how the bacterium was spreading, conditions encouraging infection, and possible control methods.
May 1, 1976
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.
May 1, 1960
Two separate variety trials were conducted on growing flowering crab apples on Malling rootstocks. The studies were conducted by Massachusetts State College and Oregon State College based on interest in size-control for landscaping plantings.
January 1, 1982
A discussion about the use of horticultural sprays and their effectiveness in controlling a wide variety of pests. The Oregon State University affiliated authors include the specifications for superior oils and the traditional caution statements.
September 1, 1976
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.
January 1, 1962
Verticillium fungus was a growing concern for geranium growers when this article was first published. The author was especially concerned for home growers and the impact Verticillium fungus would have on Oregon Willamette Valley geranium growers.
January 1, 1983
Computers were making their way into the nursery environment for everyday use and improved efficiency. Electronic marketing using a computer auction network, how it worked, the benefits involved, and other markets that were using electronic marketing are addressed by the author.
April 1, 1977
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.
August 1, 1963
Comparisons between Bartlett pear OP-9, OP-3, and various other Bartlett selections are made by the author after studies were conducted on the pear selections. OP-9 came from Mt. Adams Orchard in White Salmon, WA and the budded seedlings were given to three Oregon nurserymen for performance studies.
January 1, 1983
The Oregon State University affiliated author addresses the change in accessing available information due to the use of computers in greenhouse and nursery industries. Specific topics discussed include; databases, online services, and telecommunications.
August 1, 1977
The Oregon State University affiliated author addresses concepts in pest management regarding weeds, disease, and insects. The need for integrated pest management control measures and how an integrated program can be implemented are included in the discussion.
September 1, 1964
Variety trials were conducted on rose rootstocks in several different states. The authors had specific conditions the rose cultivars needed to meet in order to be considered viable rootstock. The results of the trials are discussed and also presented in tables.
August 1, 2008
Research was conducted on one-year-old container grown Rhododendron L. (Rhododen- dron ‘H-1 P.J.M’) and azalea (Rhododendron ‘Cannon’s Double’) to determine the influence of fall sprays of urea on the uptake of nutrients other than nitrogen (N).
April 1, 1978
The authors discuss the importance of water quality in regard to irrigation water, the source of the water used, and the various pathogens it could contain. Detection of pathogens in water, control methods, and a titration method for chlorine content are addressed.
December 1, 1965
Eight different ornamental species were planted and treated with various herbicides in a two to three year study to determine the herbicides effectiveness at weed control. The details and results of the study are discussed by the Oregon State University affiliated author.
November 1, 1978
The Oregon State University affiliated authors discuss fertilizers for container grown plants and the different factors to take into account when making or buying a fertilizer mix. The North Willamette container mix and suggestions for use are included.
April 1, 1967
Root base rot and a specific Penicillium rot was affecting the forcing of lilies in the Pacific Northwest. Studies were carried out to discover a successful control for the two rots and are discussed by the author.
July 1, 1979
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.
June 1, 1970
The influence of lily bulb maturity, temperature, and long day treatments on flowering was researched in this Oregon State University affiliated project. The three cultivars of Easter lilies tested were; 'Ace', 'Croft', and 'Nellie White'.
May 1, 1957
The effects of Cherry Crown Gall on cherry tree productivity in comparison to disease free cherry tree productivity are researched in this 1952 study. The results of the study indicate trees planted with galls on roots showed reduced vigor and infection with new galls.
March 1, 1980
A table put together by Robert Stebbins, an extension tree fruit and nut specialist in affiliation with Oregon State University. The table provides information on a variety of pear rootstocks, the general characteristics of the rootstock and limitations of the rootstock.
December 1, 1971
Readers are warned about the issues concerning leached cedar tow used for packing trees and shrubs. It was discovered that runoff from a pile of cedar tow was responsible for a fish kill and can also damage machinery. A few tips are offered on how to use cedar tow safely.
August 1, 1957
The fast forcing of Croft lilies for a specific production date is addressed by the author in this article. The results of a 1956-57 experiment are discussed which indicate optimal timelines and cultural practices.
May 1, 1981
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.
September 1, 1974
The disease Phytophthora ilicis in cut holly led to berry and leaf infection and defoliation. Tests were preformed on the cut holly stems by dipping them in solutions and leaving some untreated for comparison. After a suitable solution was found it was tested on several varieties of holly.
September 1, 1958
Croft lilies were researched in an Oregon State University affiliated study in an effort to answer practical questions in lily production. The survey of five different grower fields in Curry County, Oregon took into account soil differences and management practices in relation to bulb growth.
September 1, 1981
The Oregon State University affiliated author discusses leaf necrosis, specifically two of the frequent causes of leaf necrosis and/or defoliation. Water and heat stress, and 'anthracnose' are addressed in relation to their contribution to leaf necrosis and/or defoliation.
December 1, 1975
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
May 1, 1959
Rooting of large-flowered hybrid clematis cuttings was the subject of research in the two studies discussed by the Oregon State University affiliated author. The studies tested four rooting treatments on different varieties of clematis with varying results.
January 1, 1982
A discussion about the flatheaded apple tree borer (Chrysobothris femorata Olivier) and the Pacific flatheaded borer (Chrysobothris mali Horn). The authors offer information concerning; physical descriptions, habits, life cycle, damage, and several control methods.
May 1, 1976
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.
October 1, 1960
Research was conducted on Croft Lily bulbs and the influence the digging date had on the number of flowers produced. The author discusses the assumptions made by the industry about Croft lily bulb production in that time period in relation to the results of the research.
January 1, 1982
A thorough and informative discussion about commodity commissions in Oregon. The author addresses what commodity commissions are, how and why commissions form, general information on how they operate, and advantages and disadvantages of commodity commissions.
September 1, 1976
The importance of thermometer accuracy in regard to energy conservation in the greenhouse is discussed by the Washington State University affiliated author. Directions are provided, instructing the reader on how to properly calibrate a thermometer.