Euonymus fortunei (Turcz.) Hand.-Mazz. is susceptible to anthracnose caused by Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. Fungicides have provided little control of anthracnose on E. fortunei in past studies. Identification of cultural practices that reduce disease incidence would be beneficial to the nursery industry. Containerized E. fortunei `Emerald'N Gold' plants were placed either on gravel beds or black plastic-covered gravel beds. Half of the beds in each bed treatment were sprayed with a 10% bleach solution monthly to attempt to reduce the presence of C. gloeosporioides inoculum. Plants were rated monthly from May (initial rating) through October for disease severity. A covariate analysis was performed using initial ratings as the covariate for ratings from all other months. Bleach did not affect disease ratings at any time. Disease ratings of plants on plastic-covered beds were lower than those of plants on gravel beds. Disease ratings decreased linearly as the growing season progressed.
Cheryl R. Boyer and Janet C. Cole
Stephanie S. Ningen, Janet C. Cole and Kenneth E. Conway
Effect of night temperatures on the severity of Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. on Euonymus fortunei (Turcz.) Hand.-Mazz. rooted cuttings of `Emerald Gaiety', `Canadale Gold', and `Emerald 'n Gold' was investigated. Uniform cuttings were exposed to day temperatures of 35.3 °C and night temperatures of 19.3 °C or 28.6 °C in growth chambers. Plants exposed to a 28.6 °C night temperature had higher disease ratings than those exposed to a 19.3 °C night temperature. `Emerald Gaiety' was damaged least by C. gloeosporioides compared to `Canadale Gold' and `Emerald 'n Gold'. Disease ratings on all cultivars increased linearly over the 6-week experimental period.
Richelle A. Sink, Alfred E. Einert, Gerald L. Klingaman and Ronald W. McNew
Euonymous fortunei `Coloratus' (Turcz.) Hand.-Mazz. (purpleleaf wintercreeper euonymus) is a groundcover species commonly grown in the landscape and known for its characteristic purplish-red color in the fall. This species is dimorphic, having both juvenile and adult forms present in established plants. Young plants, planted from 5.7-cm containers, were grown under full sun and 60% shade and evaluated for 1 year from May 1998. Four fertilizer treatments, up to four applications, were applied over the year. Data collected included the percent of adult and juvenile plants per plot, percent canopy cover, plant quality, and fresh and dry weights of pruned plant material and whole plants. Results showed that 73% of Euonymus planted in the shade were “adult-like” in form, while only 44% of Euonymus planted in the sun were “adult-like” in form. These results were analyzed with the percentage canopy cover determined for March, April, and May 1999 and showed no interaction of the two variables. By the end of the study, the mean percent of canopy cover was 77% under the shade and 74% under the sun. These values were not significantly different. While it appeared that the maturity of the plant did not effect the percent of groundcover coverage in a plot, the more mature or “adult-like” plants were visually undesirable within a plot of juvenile plants, and vice versa due to morphological differences.
Cheryl R. Boyer*, Janet C. Cole and Kenneth E. Conway
Plants of Euonymus fortunei `Emerald Gaiety', `Emerald 'n Gold' and `Canadale Gold' were sprayed to runoff weekly at two sites with one of three fungicide treatments or water (control) to determine fungicide effectiveness in controlling anthracnose caused by Colletotrichum gloeosporioides. Copper sulfate pentahydrate was applied at 0.4 or 0.6 g·L-1 a.i. or mancozeb was applied at 1.8 g·L-1 a.i.. Plants were rated for disease incidence approximately monthly. No interaction occurred between fungicide and cultivar. Differences among fungicide treatments were not apparent until weeks 18 or 20 depending on the site, when plants treated with mancozeb had lower disease ratings than plants receiving any other treatment. Cultivars differed at almost every rating date at both sites. Poison agar experiments were conducted to determine mycelial inhibition by copper sulfate pentahydrate or mancozeb.
Stephanie S. Ningen, Janet C. Cole, Michael W. Smith, Diane E. Dunn and Kenneth E. Conway
The effectiveness of shade intensity and time of day in which irrigation was applied were tested for control of anthracnose symptoms caused by Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. on container-grown Euonymus fortunei (Turcz.) Hand.-Mazz. `Canadale Gold', `Emerald 'n Gold', and `Emerald Gaiety' during the 2002 and 2003 growing seasons. Rooted cuttings in 3.8 L containers were placed in 0% (full sun), 63%, 73%, or 80% shade at Park Hill, Okla., in 2002 and 2003 and at Stillwater, Okla., in 2002. Overhead irrigation was used to irrigate one-half of the plants in each cultivar and shade treatment in the morning and the other one-half during the afternoon. At both sites, disease damage ratings were inversely related to shade intensity throughout each growing season. Disease incidence was usually lower on afternoon irrigated plants than on morning irrigated plants. `Canadale Gold' typically had the most anthracnose symptoms followed by `Emerald 'n Gold'. `Emerald Gaiety' had the least symptoms regardless of shade intensity or irrigation time.
Cheryl R. Boyer, Janet C. Cole and Mark E. Payton
anthracnose on wintercreeper euonymus J. Environ. Hort. 25 21 26 Cole, J.T. Cole, J.C. Conway, K.E. 2005 Effectiveness of selected fungicides applied with or without surfactant in controlling anthracnose on three cultivars of Euonymus fortunei J. Appl. Hort
R.A. Sink, A.E. Einert, G.L. Klingaman and R.W. McNew
Use of groundcovers in the landscape is often limited due to their slow establishment rate compared to that of turf. Hedera helix L., (English ivy), Euonymus fortunei `Coloratus' (Turcz.) Hand.-Mazz. (purpleleaf wintercreeper euonymus), and Liriope spicata Lour. (creeping lily-turf) were evaluated in a full sun and 50% shade environment to determine the effects of fertilizer applications on their establishment and growth. Fertilizer treatments, of 13N-13P-13K at a rate of.45 kg/93 m2, used were: 1) at planting only; 2) at planting and once during the summer; 3) at planting, in summer, and once in the fall; or 4) at planting, in summer, in fall, and once the following spring. Data collected included fresh and dry weight comparisons of pruned material, percentage canopy cover, plant quality and vigor by visual assessment and photographs, and time required for maintenance of each plot. Results show limited fertilizer effects and interaction according to species during the first several months of growth. Establishment and survivability of Hedera was influenced mainly by light exposure rather than fertilizer applications. There was no difference in establishment rates between Liriope and Euonymus, however, under shade, Euonymus did not develop its characteristic fall color. Hedera was established in one season under 50% shade and can be considered very competitive with turf under the same conditions.
Stephanie L. Schupbach-Ningen, Janet C. Cole, James T. Cole and Kenneth E. Conway
The effectiveness of chlorothalonil, mancozeb, and trifloxystrobin applied alone or in rotations of two or three fungicides to control anthracnose symptoms caused by Colletotrichum gloeosporioides was evaluated on three cultivars of field- and container-grown wintercreeper euonymus (Euonymus fortunei) during the 2001 growing season. Studies were conducted at Stillwater, Okla.; Fayetteville, Ark.; and Park Hill, Okla. Rooted cuttings of wintercreeper euonymus `Emerald Gaiety', `Emerald 'n Gold', and `Emerald Surprise' were transplanted from 1-gal plastic containers into field soil at the Oklahoma State University Nursery Research Station and at the University of Arkansas Horticulture Farm on 10 May 2001. In a parallel study, recently transplanted rooted cuttings of the same cultivars in 1-gal pots containing substrate consisting of pine bark and sand were placed in a shadehouse under 30% shade at Stillwater and Fayetteville and 73% shade at Park Hill on 11 May 2001. `Emerald Gaiety' had fewer disease symptoms than `Emerald 'n Gold' or `Emerald Surprise' in the field and in containers at Stillwater and Fayetteville. At Fayetteville, mancozeb applied alone or in rotation with chlorothalonil or trifloxystrobin provided better anthracnose control than treatments without mancozeb, but no fungicide eliminated anthracnose symptoms. Application of fungicides in rotations that include mancozeb and use of resistant cultivars can help decrease anthracnose symptoms.
Jayesh Samtani, Gary Kling* and David Williams
Conventional herbicide applications to container-grown landscape plants, often requires multiple spray applications of herbicides in a growing season and presents problems such as non-uniform application, leaching, run-off, environmental pollution, worker exposure and phytotoxicity to the landscape plants. The use of an organic herbicide carrier could help reduce some of the problems associated with spray applications. Landscape-leaf waste pellets were evaluated as a preemergent herbicide carrier for container-grown landscape plants. Isoxaben, prodiamine and pendimethalin were applied to Chrysanthemum × grandiflorum `Lisa', Euonymus fortunei `Coloratus' and Spiraea japonica `Neon Flash', at rates of 1.12, 2.25, and 2.25 kg·ha-1 active ingredient, respectively, with either water or landscape leaf waste pellets as a carrier. Portulaca oleracea, Senecio vulgaris, and Setaria faberi were seeded following treatment application. Visual ratings on efficacy and photoxicity to landscape plants, and shoot fresh and dry biomass were determined for both weeds and crop plants. Landscape leaf pellets served as an effective carrier for application of prodiamine and pendimethalin and combinations of these herbicides with isoxaben in controlling weeds. Leaf waste pellets as a carrier produced equivalent weed control and phytotoxicity ratings to conventional spray application of these herbicides, on both Chrysanthemum and Euonymus. The pellets did not make a consistently effective carrier for the application of isoxaben alone. Application of herbicides on leaf pellets could result in more uniform herbicide applications, minimize loss of herbicides to the environment and reduce the risk of herbicide contact with nursery workers.
C. Chong, J. Yang, B. E. Holbein, R. P. Voroney, H. Zhou and H.-W. Liu
Cuttings of sage (Salviaofficinalis `Tricolor'), currant (Ribesaureum), euonymus (Euonymus fortunei var. vegetus), and weigela (Weigela florida `Nana Variegata') were rooted under greenhouse conditions (40% shade) and mist in aerated hydroponic solutions consisting of deionized water, or mixtures of deionized water and nutrients with various levels of electrical conductivity (EC, 0.0625, 0.125, 0.25, and 0.5 dS·m-1) from each of three sources: compost tea from municipal solid waste; wastewater from anaerobic digestion of municipal solid waste; and Hoagland's (control) nutrient solution. Despite differences in species response, rooting tended to be similar with the three nutrient sources. Euonymus rooting percentage increased linearly with increasing EC and was similar with all three nutrient sources (common regression curve, 61% rooting at 0.5 dS·m-1), as did root length (1.4 cm at 0.5 dS·m-1), but root number was unresponsive. Currant rooting percent increased curvilinearly and similarly with nutrient sources (87% calculated maximum rooting at 0.25 dS·m-1), but root number and length were unresponsive. Sage rooting percentage and root number also increased curvilinearly and similarly with nutrient sources (common regression curve, 100% rooting at 0.34 dS·m-1, and 4.1 roots at 0.38 dS·m-1, respectively), as did also root length with the compost tea and Hoagland's (common curve for these two nutrient sources, 11.0 cm at 0.30 dS·m-1), but was unresponsive to wastewater. Weigela was unresponsive to EC or nutrient sources (mean percentage of rooting, 73; root number, 6.5; and root length, 1.9 cm).