system are grown as 14-month crops on peach, plum, or hybrid rootstocks. Weed control is an ongoing management problem faced by producers of field-grown nursery stock. Competition from weeds can decrease crop productivity and interfere with field and
Mary Joy M. Abit and Bradley D. Hanson
Houchang Khatamian and Alan Stevens
The main purpose of this study was to determine consumer preferences as influenced by type of packaging, size of container, and price when purchasing ornamental plants. From February to May 1991 over 1000 questionnaires were completed through personal on site interviews conducted at Flower/Garden shows and Garden Centers.
Forty one percent of participants preferred to purchase their trees as balled in burlap form and 47% chose to buy their shrubs in containers. Shoppers purchased 60% of their nursery plants from Garden Centers followed by 22% at discount outlets such as K-mart.
The most important factors in purchasing nursery stock were the price and quality of the plants followed by its size. Packing was an important factor but ranked much lower than price and quality.
Mark M. Bray, John R. Clark, and Rose Gergerich
In 2004, two surveys were conducted to assess the presence of four viruses in marketable blackberry nursery stock. The U.S. survey consisted of dormant nursery stock received from 11 nurseries in the southern, southeastern, midwestern, northeastern, and Pacific northwestern regions of the U.S. The second survey was focused only on Arkansas licensed propagating nurseries with samples collected during the growing season. Samples were tested using reverse transcription–polymerase chain reaction or enzyme-linked immunosorbent assay for the presence of Blackberry yellow vein associated virus (BYVaV), Raspberry bushy dwarf virus (RBDV), Tomato ringspot virus (ToRSV), and Tobacco ringspot virus (TRSV). Of the total samples in the U.S. survey, there were 9% that tested positive for virus infection. Ninety percent of the positives were infected with BYVaV. Forty percent of these were detected in `Triple Crown', 40% in `Chickasaw', and 20% in `Apache'. The remaining 9% of the total positive virus samples were infected with TRSV and 100% of these were in `Triple Crown'. No viruses were found on any samples of `Chester Thornless'. In the Arkansas survey, 11% of the total samples tested positive for virus. Of these, 50% were infected with BYVaV.
The percent infected with BYVaV was distributed evenly among `Apache', `Chickasaw', and `Kiowa'. The other 50% of the infected samples were positive for TRSV (67% `Apache', 33% `Chickasaw'). There was one mixed infection of BYVaV and TRSV detected in `Apache'. These findings indicate that BYVaV is the most prevalent virus found in nursery stock and that the occurrence of BYVaV is not restricted to a single region or cultivar.
D.E. Deyton, C.E. Sams, D.C. Fare, R.E. Moran, and C.D. Pless
Our research has previously shown that soybean oil can substitute for petroleum oil for controlling insects on fruit trees. Soybean oil may also be a safe, environmentally friendly pesticide to use on nursery stock. The objectives of these experiments were to evaluate phytotoxicity of soybean oil to nursery stock and efficacy for mite control. Four replications of container-grown plants of `Alberta' spruce, `Emerald' arborvitae, `Leyland' cypress, Canadian hemlock, and `Andorra' juniper were sprayed on 26 Mar. with 0%, 1.0%, 2.0%, or 3.0% soybean oil; or 2.0% petroleum oil. None of the oil treatments caused phytotoxicity. The same plants were sprayed on 1 Aug. with 0%, 1.0%, 2.0%, or 3.0% soybean oil. Application of 1% or 2% soybean oil appeared to be non-phytotoxic to spruce, but 3% soybean oil caused slight terminal necrosis. Arborvitae, cypress, hemlock, and juniper were not injured by spraying 1% to 3% soybean oil in the summer. Container-grown burning bush plants with mite infestations were sprayed on 20 Sept. with 0%, 1.0%, 2.0%, or 3.0% soybean oil; or with 1.0% SunSpray petroleum oil. Container-grown mite-infested `Andorra' juniper plants received the same treatments, except for the 3% soybean oil. Application of 1% or 2% soybean oil to burning bush or to juniper shrubs resulted in >97% and 87% control of mites 7 and 14 days, respectively, after treatment.
Larry D. Makus, John C. Foltz, Joseph F. Guenthner, and Robert R. Tripepi
Survey data from 3 11 garden centers, landscapers, and combined garden center/landscaping firms in selected western United States trade centers were analyzed. Results identified important product and service attributes used in respondent decisions to purchase nursery stock. In general, product characteristics were ranked higher than supplier services. The highest-ranked product characteristics included plants free of insects and disease, properly dug and handled container or balled and burlapped stock, properly dug and handled bare root stock, and plants available when needed. However, several additional product characteristics received high rankings. The highest-ranked service was supplier knowledgeable about plant materials. A χ2 analysis was conducted to segment this market on the basis of firm size, business type, and geographic location. Results indicated there were limited between-group differences to use in segmenting the market on the basis of size, business type, or location.
Ursula K. Schuch
A two-part exercise was developed as part of the horticulture curriculum at Iowa State University to familiarize students with the American Standard for Nursery Stock (ASNS), and to allow them to practice and apply the ASNS with a variety of categories and types of ornamental plants. The first part of the exercise requires students to determine, according to ASNS standards, appropriate root ball/container size for plants to be moved from an existing immature landscape. During the second part, students evaluate whether root ball or container size of plants in a nursery is appropriate for the plant shoot dimensions. The exercise was designed for students to work in informal groups in a cooperative learning environment.
Fenton E Larsen and Stewart S. Higgins
Many tree fruit nurseries are limited to fall digging of deciduous nursery stock. Since trees may not defoliate naturally for timely digging, these nurseries may wish to defoliate chemically, which would be less expensive than hand-stripping and may more closely simulate natural leaf abscission. Consequently, test chemicals were applied with hand sprayers at commercial nurseries in central Washington State using single or double applications 1 wk apart. In 1992 on 7 apple cultivars and one pear, 500 ppm NPA + 150 ppm Ethrel significantly enhanced defoliation. Defoliation at 1000 ppm NPA was not superior to that at 500 ppm, and two applications were generally no better than one. However, in 1993, two applications were often more effective than one, and the addition of Ethrel to NPA generally enhanced defoliation if the combination of NPA + Ethrel was applied twice. Alanap and NPA were generally equally effective as defoliants. The addition of Ethrel to Alanap enhanced defoliation in only 3 of 9 cultivars, and then generally only when sprayed twice. Alanap + Ethrel was as effective with Alanap at 300 ppm as with Alanap at 500 ppm Ethrel by itself seldom increased defoliation.
John D. Lea-Cox and Irwin E. Smith
Pine bark is utilized as a substrate in citrus nurseries in South Africa. The Nitrogen (N) content of pine bark is inherently low, and due to the volubility of N, must be supplied on a continual basis to ensure optimum growth rates of young citrus nursery stock. Three citrus rootstock (rough lemon, carrizo citrange and cleopatra mandarin) showed no difference in stem diameter or total dry mass (TDM) when supplied N at concentrations between 25 and 200 mg ·l-1 N in the nutrient solution over a 12 month growing period. Free leaf arginine increased when N was supplied at 400 mg·l-1 N. The form of N affected the growth of rough lemon. High NH4-N:NO3-N (75:25) ratios decreased TDM when Sulfur (S) was absent from the nutrient solution, but not if S was present. Free arginine increased in leaves at high NH4-N (No S) ratios, but not at high NH4-N (S supplied) ratios. Free leaf arginine was correlated with free leaf ammonia. These results have important implications for reducing the concentration of N in nutrient solutions used in citrus nurseries and may indicate that higher NH4-N ratios can be used when adequate S is also supplied.
Kathleen M. Kelley, N. Curtis Peterson, and G Stanley Howell
The loss of container-grown nursery stock during winter months may be due to lack of root hardiness when exposed to cold temperatures. After Euonymus alatus `Compactus', Weigela florida `Java Red', and Hibiscus syriacus `Paeonyflora' reached midwinter hardiness, replicates of each cultivar were subjected to 12 hours of 21°C followed by 12 hours of 0°C each 24-hour period for up to 16 days. Controlled temperature freezing was conducted after each 48-hour period, with temperatures ranging from –6 to –27°C to determine the level of root hardiness. Plants were placed in a greenhouse environment to observe post-stress performance. Weigela was the most cold hardy, followed by Euonymus and Hibiscus. In general, the early accumulation of warming temperatures decreased root hardiness and delayed budbreak, with a noticeable loss of vigor. Results of this research will be presented.
Eugene J. Hague and Denise Neilsen
A system for the rapid production of Ottawa-3 (0.3) rootstock (Malus domestica Borkh.) and branched apple nursery stock in the greenhouse is described. The time required for production of a finished' tree, ≈1 year, compared favorably with traditional methods. Cuttings derived from tissue-cultured 0.3 rootstocks rooted well (up to 94% success rate), and the rooting effect persisted in cuttings from tissuecultured rootstocks grown for 1 year in the field. All combinations of two levels of N and P in a Long Ashton nutrient solution were applied weekly to pots containing either tissue-cultured rootstocks or cuttings. The growth rate of tissue-cultured rootstocks exceeded that of cuttings. The growth rate of both sources of rootstocks increased in response to added P and N. Growth of scion shoots (`Royal Gala') increased in response to N. Branch production of `Royal Gala' was greater for trees with the higher P and N rates. Trees on tissue-cultured rootstocks had more branches than those on cuttingderived roostocks at the higher level of N.