Three field experiments were conducted to determine short- and long-term effects of hydrogel mixed with peatmoss, milled pine bark, or soil on growth and yield of blueberry. Rabbiteye blueberry cultivars (Vaccinium ashei Reade) Delite, Tifblue, and Climax, and southern highbush cultivar (V. corymbosum L.) Georgiagem were used as test plants. Hydrogel mixed with soil was detrimental to plant survival. Hydrogel with or without peatmoss or pine bark did not influence yield or berry weight of 3- to 4-year-old `Delite' and 2- to 3-year-old `Tifblue' plants. The southern highbush, `Georgiagem', grown in peatmoss + hydrogel, produced plants of larger volume than those grown in peatmoss alone. Yield or berry weight was not affected significantly by soil amendments. Genetic differences between cultivars affected growth, yield, and berry weight, but the cultivar x soil treatment interaction was not significant.
Max E. Austin and K. Bondari
M.P. Garber and K. Bondari
Results of a national survey indicated that the top four sources of information used by garden writers for new or appropriate plants were nursery catalogs, botanical and public gardens, seed company catalogs, and gardening magazines. More than 50% of the participating garden writers reportedly used these four sources a lot. The most frequently used books and magazines were Horticulture Magazine (34.6%), Manual of Woody Landscape Plants (24.1%), and Fine Gardening (23.7%). About 29% of the garden writers used the World Wide Web to source information and the two most widely used type of sites were universities and botanical gardens and arboreta. A high percentage of garden writers desire greater or more frequent communications with botanical gardens and arboreta (90.4%), university personnel (87.4%), and plant producers (86.3%).
M.P. Garber and K. Bondari
A survey of landscape architects in Georgia was conducted to identify opportunities for nurseries to meet the needs of landscape architects and to improve the quality of installed landscapes. The primary opportunities identified for improvement for growers are to provide regular, frequent plant availability (32% of respondents); develop new plant varieties for specific needs (21%); supply plants that meet specified sizes (20%); recommend plant varieties for specific conditions (12%); provide picture of plants (9%); and make presentations to landscape architects (5%). Additional insight into how growers can help landscape architects achieve a higher quality installed landscape was gained from the question, `What is the most common complaint you experience regarding plant material installed?” Landscape architects indicated that plants below specified size (44%) and plants below specified quality (24%) were the two most common complaints.
M.P. Garber, J. M. Ruter, J.T. Midcap and K. Bondari
A 2001 survey of 102 nurseries that were members of the Georgia Green Industry Association was conducted to assess irrigation practices of container ornamental nurseries. Mean nursery size was 64 acres (26 ha) and mean annual revenue was about $3 million. About 50% of the irrigation water was from wells and the other 50% came from surface sources, such as collection basins. Irrigation in smaller containers, including #1, #3, and #5, was applied primarily by overhead methods, while larger containers (#7, #15, #25) made extensive use of direct application methods, such as drip or spray stakes. Frequency of irrigation in the summer growing months was about three times that of the winter season. Georgia nurseries use irrigation practices suggested in Southern Nursery Association best management practices, including collection of runoff water (48%), cyclic irrigation (44%), watering in the morning (92%), and grass strips between the production beds and drainage areas (60%).
Melvin P. Garber, William G. Hudson, Jeffrey G. Norcini, Ronald K. Jones, Ann R. Chase and Kane Bondari
A national survey of the greenhouse and nursery industries was conducted to determine the current status of pest management practices. This study covers the trends in chemical and nonchemical pest control measures and factors that affect adoption of nonchemical control measures. For the 5-year period 1988-93, there appeared to be a decrease in chemical use for disease and insect control and for plant growth regulators. During the same period there was an increase in chemical weed control. The adoption of nonchemical pest control measures was concentrated in the area of insect control. The primary factors limiting use of nonchemical pest control measures were 1) availability of effective materials/biological agents, 2)availability of information, and 3) management complexity. The primary information sources on nonchemical pest control used by growers varied by size of firm and region of the country. For all respondents the primary sources were 1) industry trade journals, 2) other growers in the industry, 3) cooperative extension service, and 4) industry-sponsored seminars.
Ronald K. Jones, Ann R. Chase, Melvin P. Garber, William G. Hudson, Jeffrey G. Norcini and Kane Bondari
A national survey of the commercial ornamental industry was conducted to determine the current status of pest control including chemical and nonchemical disease control practices. The fungicides thiophanate methyl, chlorothalonil, mancozeb, and metalaxyl were used in the greatest quantity and by the largest percentage of growers. Metalaxyl was used in greenhouse and field operations by the highest percentage of growers, primarily to control root diseases but many growers reported using metalaxyl to control foliar disease. Overall, more fungicides were used in the field for foliar diseases, whereas almost equal amounts of fungicides were used for foliar and root diseases in the greenhouse.
Jeffrey G. Norcini, William G. Hudson, Melvin P. Garber, Ronald K. Jones, Ann R. Chase and Kane Bondari
Growers in the American Association of Nurserymen and the Society of American Florists were queried as to their use of plant growth regulators (PGRs) and nonchemical alternative practices during 1993. Daminozide (B-Nine SP) and chlormequat chloride (Cycocel) accounted for 78% of the total pounds active ingredient and were used by 20% and 17% of the respondents, respectively. In contrast, the rooting compounds indolebutyric acid (Dip `N Grow, Rootone, and Hormoroot) and naphthaleneacetic acid (Dip `N Grow, and Hormodin I, II, and III) were used by 53% and 24% of the respondents, respectively, but combined accounted for less than 3% of total pounds active ingredient. Pruning/pinching was used by the greatest number of respondents (82%) and was the only alternative to PGRs rated as very effective by more than 60% of the respondents. Use of chemical PGRs and nonchemical alternative practices was influenced by region and firm size. In the northeastern United States, growers reported relatively low use of PGRs (frequency and total pounds) and the lowest use of mechanical brushing as an alternative practice. In contrast, mechanical brushing was used most in the western United States. Large firms (more than $2 million in annual sales) reported the greatest use of chemical and nonchemical means of regulating growth.
Jeffrey G. Norcini, Melvin P. Garber, William G. Hudson, Ronald. K. Jones, Ann. R. Chase and Kane Bondari
Members of the American Association of Nurserymen and the Society of American Florists were surveyed as to their use of herbicides and nonchemical alternative weed control practices for 1993. Glyphosate was the top-ranking herbicide among the total of 37 reported, in terms of number of respondents and estimated total amounts of active ingredients applied. It was used by all but two of the respondents that used herbicides in their operations. Oryzalin was the top-ranked preemergent herbicide, and was second only to glyphosate in number of respondents and amount of active ingredient applied. The highest estimated use in amounts of active ingredient applied was in the southeastern (43% of total) and north-central (27% of total) regions, nearly two to three times the estimated use in the northeastern or western regions. However, there were only about 50% more respondents in the southeastern or north-central regions compared to the other regions. About 56% of herbicide active ingredients used were in field sites, 22% in container sites, 19% in perimeter areas, and 3% in green-houses. Large firms (annual sales more than $2,000,000) used the greatest estimated total amount of active ingredients, while small firms (annual sales more than or equal to $500,000) tended to use nonchemical alternatives the most. Nearly all respondents used handweeding or hoeing as part of their weed control program. Mowing was used by 84% of the respondents, 71% used tractor cultivation, and 66% used mulches (includes gravel and black plastic). Alternative methods were rated as somewhat effective to very effective by 65% or more of the respondents who used them.