opportunities for nursery growers. Several prior efforts have been undertaken to quantify cost estimates for various ornamentalplant production systems in the southeastern U.S. ( Hall et al., 1987 ; Hinson et al., 2007 ; Taylor et al., 1986 , 1990
varieties. GE is supported by rapidly expanding science and technology but, to our knowledge, has not led to any commercial releases for woodyornamentalplants. We will consider the technical approaches and limitations of both approaches as well as the
When one searches the literature for information pertaining to the nutrition of woody ornamental plants it soon becomes obvious that there has not been too much published in this field. And most of the experimental work on the nutrition of trees has been concerned with varying combinations of nitrogen, phosphorus and potassium. Also, most of the work that is reported was done in the field, either to trees growing in the landscape or in nurseries and as a result most of the studies report a positive response only to the application of nitrogen and little or no response to the application of phosphorus or potassium. A brief review of some of the literature on fertilizer experiments is contained in the works of Wikle (18) and Himeleck (9). Since this symposium is concerned with potassium in horticulture, I will confine most of my remarks to the place that this mineral element has on the growth and development of woody ornamental plants.
Stems of many woody ornamental plant taxa were collected in midwinter and hardened to their maximum capability under laboratory conditions. Hardiness levels were determined and compared to zone recommendations as listed in Hortus III and Rehder’s Manual of Cultivated Plants. Many woody plants had a greater midwinter cold tolerance than their hardiness ratings would infer.
Quality, the degree of excellence which a thing possesses, varies with the evaluator for excellence to one may be mediocrity to another. After considerable thought and examination of the literature, I have concluded that the quality attributes of woody ornamental plants as affected by mineral nutrition practices are not well defined. First, how exactly does one proceed to evaluate quality in a woody ornamental plant? The effects of mineral nutrition on the quality of vegetables and fruits would appear to be more obvious. Yield, color, firmness, taste, keeping quality, and chemical components may be useful traits for evaluating quality under a given set of nutritional, cultural, and environmental conditions In general quality on woody ornamentals appears to be related to visually pleasing, salable plants. There are various reports of fertilizer sources and rates on growth or appearance. I will review a limited number of these and then discuss the results of a questionnaire which was sent to nurserymen around the country concerning fertilization and woody ornamental plant production.
Web sites such as the University of Connecticut (UConn) Plant Database allow large volumes of information and images to be stored, published and accessed by users for the purpose of informed decision-making. Sorting information on the World Wide Web (Web) can be difficult, especially for novice users and those interested in quick results. The advent of Internet search and retrieval software fosters the creation of interactive decision support systems. The Plant Selector was designed to complement the UConn Plant Database plant encyclopedia by allowing Web site users to generate lists of woody ornamental plants that match specific criteria. On completion of an HTML-based search form by users, a Web-enabled database is searched and lists of matching plants are presented for review. To facilitate analysis of the Plant Selector's efficacy, an online questionnaire was implemented to solicit user feedback. Survey data from 426 responses to the online evaluation tool were analyzed both to understand user demographics and gauge satisfaction with the Plant Selector module. Survey data revealed that most Plant Selector users are between 40 to 65 years of age and homeowners with minimal horticultural experience. A large percentage of Web site visitors (68%) is located across the United States beyond Connecticut and the New England region. The great majority of survey respondents (65%) use this tool to select plants for the home landscape. Most (77%) either agree or strongly agree that the Plant Selector is easy to use and delivers results that are useful (66%), while 70% agree or strongly agree that the categories used by the Plant Selector are sufficient. The survey results in general suggest that Web-based decision support systems may serve useful roles in the field of horticulture education.
Commercially acceptable growth rates of woodyornamental nursery stock can be achieved using managed allowed deficits, i.e., deficit irrigations, of 20% to 40% plant-available water (PAW) before initiating irrigation ( Beeson, 2006 ; Welsh and
Slow-release fertilizers (SRF) are greatly used in container production in addition to an hebdomadal fertigation regime. For economic and environmental motives, growers wish to restrict fertigations. The objectives of this paper are to characterize the release patterns of several SRF and to determine the benefits of these fertilizers on the growth of selected woody ornamental plants. The SRF used in this study were: Osmocote®, Nutricote®, Polyon®, Nutralene® and Woodace®. The two first parts of the study were conducted in a greenhouse in Marsh 1993, with Weigela florida `Rumba' in the first part and without plant in the second one. Fertilizers were top dressed according to a medium suggested concentration. The third part of this study was done in the field in June 1993, with the same fertilizers applied in three concentrations as follow: low suggested concentration (SC), 1.5× SC and 2× SC. Two species were tested in this part, Weigela florida `Rumba' and Spiraea bumalda `Goldflame'. Growth was measured by the height of the plant, the width of canopy and the dry mass of leaves, stems and roots. Samples leachate were collected weekly or monthly for greenhouse and field studies respectively. Leachates were analysed for their mineral content per dry mass of plant tissue and the results will be presented on the poster. In the third study, plants gave a comparable growth with the first and the third fertilizer concentrations.
The objective of this study is to determine the phytotoxicity and efficiency of oxadiazon and sethoxydim used as herbicide in the production of four species of woody ornamental plants grown in containers. Four species were used: Cornus alba `Argenteo Marginata', Weigela florida `Rumba', Prunus x cistena and Thuja occidentalis `Woodwardii'. Six herbicide treatments were used (oxadiazon at 0,4 and 8 Kg (a.i.)/ha; sethoxydim at 0.000, 0.276 and 0.552 Kg (a.i.)/ha) and two controls were added (weeding and unweeding). The eight treatments were included in a complete block design replicated six times. This project was started in July 1993 and was conducted for three months. If phytotoxic symptoms were present on plants they were recorded and their effects on growth was measured. At the end of the experiment, weeds present in pots were identified, counted and their growth measured. Preliminary results showed that oxadiazon applied at rates of 4 and 8 Kg (a.i.)/ha had a good efficiency weed control in container production. Sethoxydim applied at rates of 0.276 and 0.552 Kg (a.i.)/ha had a good grass control. The two herbicides did not show phytotoxic symptoms on the for species used. The effects of herbicides on plant growth will be presented.