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Gary W. Knox, Fred Burkey and Christine Kelly-Begazo

The Florida Yards & Neighborhoods Program (FYN) provides special educational and outreach activities directed at the community to help Floridians reduce pollution and enhance their environment by improving landscape management. The Commercial Landscape Industry Professionals program (CLIP) was developed to provide training in FYN principles to Florida's landscape professionals. CLIP was pilot-tested from 1997 to 1999 in the six-county Indian River Lagoon area of coastal east-central Florida. Teaching resources, audiovisuals, teaching outlines, and reference materials were developed to create an FYN/CLIP curriculum, which was delivered to landscape maintenance personnel through a series of training programs. In addition, the pilot program developed marketing approaches, incentives, and recognition programs for landscape professionals to encourage their participation in CLIP training programs. Evaluations of training programs and results of pre- and post-test questionnaires demonstrate the effectiveness of the FYN/CLIP program.

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Glenn D. Israel, Janice O. Easton and Gary W. Knox

The Florida Cooperative Extension Service (FCES) teaches residents the importance of proper landscaping practices. FCES offers several educational programs that teach residents how to integrate energy and water conservation, pest management, and waste recycling practices into their home landscapes. In 1997, extension staff and volunteers planned and conducted environmental landscape management (ELM) programs resulting in >800,000 customer contacts. A survey was conducted to measure the adoption of recommended best management practices by program participants and nonparticipants. Results show that, of 39 practices examined, Master Gardener trainees increased the number of practices used by an average of 7.3, while educational seminar and publications-only participants increased by an average of 4.5 and 2.8 practices, respectively. Nonparticipants showed essentially no change. When practices are examined one at a time, the Master Gardeners made statistically significant increases in 28 of the 39 recommended practices. Educational seminar and publications-only participants made similar gains in 31 and 6 practices, respectively, and the nonparticipant comparison group made significant increases in 2 practices and decreases in 8. The results suggest that the publications-only strategy for delivering information to homeowners is less effective than strategies combining educational seminars or intensive training with relevant publications.

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Sandra B. Wilson, Gary W. Knox, Keona L. Nolan and James Aldrich

Chinese privet (Ligustrum sinense) and glossy privet (L. lucidum) have been classified as Category I invasives in Florida. The closely related japanese privet (L. japonicum) has escaped cultivation but is not considered a problem species in Florida. Plant growth, visual quality, flowering, and fruiting were assessed for the resident species (wild-type form) and selected cultivars of chinese privet, glossy privet, and japanese privet planted in northern and southern Florida for 132 weeks. Visual quality varied by site, month, and cultivar. With the exception of ‘Swift Creek’ chinese privet (which did not survive in southern Florida), all cultivars survived the study. All plants fruited in northern Florida. In southern Florida, fruiting was less abundant and not observed for ‘Jack Frost’ japanese privet, ‘Rotundifolium’ japanese privet, ‘Swift Creek’ chinese privet, ‘Suwannee River’ hybrid privet, and glossy privet within 132 weeks. In northern and southern Florida, the growth index rate was lower for ‘Lake Tresca’ japanese privet, ‘Rotundifolium’ japanese privet, and ‘Suwannee River’ hybrid privet than other cultivars. There was a significant interaction between temperature and species for seed germination. Germination in incubators set with a 12-hour photoperiod ranged from 51% to 78.5% for chinese privet, japanese privet, and glossy privet among temperatures, with the exception of glossy privet at 35/25 °C, where only 2.0% of seeds germinated. Germination in complete darkness ranged from 39.5% to 80.5% for chinese privet and glossy privet among temperatures, with the exception of glossy privet at 35/25 °C, where only 0.5% of seeds germinated.

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Wayne W. Hanna, Brian M. Schwartz, Ann R. Blount, Gary Knox and Cheryl Mackowiak

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Mohammed I. Fetouh, Abdul Kareem, Gary W. Knox, Sandra B. Wilson and Zhanao Deng

A number of privet species (Ligustrum spp.) that are important to the nursery and landscape industry have escaped cultivation and become invasive or weedy in the United States and other countries. Induced tetraploids in these species may produce new selections or cultivars with reduced or eliminated invasive potential. Applying drops of semisolid agar containing 0.1% to 0.3% colchicine and 0.2% dimethyl sulfoxide (DMSO) to newly emerged seedlings of japanese privet (Ligustrum japonicum Thunb.) resulted in 15.6% to 22.6% tetraploid induction. The nuclear DNA content of tetraploids was 5.31 pg/2C, 101.9% higher than that of diploids. Compared with diploid plants, tetraploids were more compact, with an average of 31.0% shorter plant height and 33.1% smaller canopy width. Tetraploids had 29.2% thicker internodes, and their leaves were 39.5% larger and 33.8% thicker, resulting in 42.1% to 24.1% greater fresh or dry leaf weights (per leaf) in tetraploids compared with diploids. Without indole-3-butyric acid (IBA) treatment, cuttings from tetraploids showed 28% lower rooting than diploids. IBA treatments improved the rooting of tetraploid cuttings, resulting in 65% rooting success. These results indicate that tetraploids can be readily induced in japanese privet and induced tetraploids show significant changes in plant growth and size, shoot growth, leaf morphology, and rooting of cuttings. The modified tetraploid induction method and the induced tetraploids are expected to be useful for producing new selections or cultivars with reduced invasive potential in japanese and other privets.

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Sandra B. Wilson, Gary W. Knox, Zhanao Deng, Keona L. Nolan and James Aldrich

A wild-type selection of heavenly bamboo (Nandina domestica) and eight cultivars were evaluated in northern and southern Florida for 144 weeks. Onset of flowering generally began by April and May in southern Florida and 4 to 8 weeks later in northern Florida. Fruit was first noted 4 to 8 weeks after most cultivars began flowering. Landscape performance and fruit production varied widely among taxa and location. ‘AKA’, ‘Firehouse’, ‘Firepower’, and ‘Firestorm’ heavenly bamboo did not flower or fruit in either location. Greater plant growth, survival, and fruiting were observed in northern Florida than in southern Florida. In both locations, the wild-type form of heavenly bamboo produced more fruit than ‘Alba’, ‘Gulf Stream’, ‘Monfar’, and ‘Moyer’s Red’. Seed viability was fairly consistent among fruiting cultivars, ranging from 69% to 89%. Nuclear DNA content and ploidy analysis indicated that all nine nandina cultivars were diploids, suggesting that tetraploidy is not the genetic cause of the non-fruiting trait in ‘AKA’, ‘Firehouse’, ‘Firepower’, and ‘Firestorm’. Results of this study offer insight into future non-invasive heavenly bamboo breeding efforts and emphasize the importance of cultivar and geographic distinctions when regarding the invasive status of a species.

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David M. Czarnecki II, Sandra B. Wilson, Gary W. Knox, Rosanna Freyre and Zhanao Deng

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Edward F. Gilman, Gary W. Knox, Catherine A. Neal and Uday Yadav

Lagertroemia indica L. × fauriei Koehne (`Natchez' crape myrtle) crown width increased after 13 months as irrigation frequency increased from every 3 days to every day, and the irrigated area around the fabric container increased from 20% to 100% of the circular area within 20 cm beyond the container. Restricting irrigation to within the fabric container plus 20% of the area 20 cm beyond the container edge resulted in less height and width for crape myrtle, but had no effect on root growth, compared to irrigating 100% of area 20 cm beyond the container. Restricting the pattern of irrigation to the container plus 20% of the area 20 cm beyond the container resulted in greater free-root weight (roots < 5 mm in diameter) within the container for laurel oak (Quercus laurifolia Michx.) compared to irrigating the container plus 100% of the area 20 cm beyond the container. Height, width, and caliper of oak were not different among treatments.

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Benjamin D. Anderson, Gary W. Knox, Ann R. Blount, Cheryl L. Mackowiak and Edward F. Gilman

Rhizoma peanut has the potential for use as an ecologically friendly groundcover or turf alternative. Little is known about height and cover characteristics of this plant, which are important ornamental considerations. The objectives of this field study were to characterize maximum average canopy height, height variability, the time to reach full canopy cover, and the time at full canopy cover of seven released and nine experimental selections of rhizoma peanut grown in full sun or under 30% shade at two North Florida locations. Greater height and a less uniform canopy were observed for shaded plants. Establishment, as measured by full canopy cover, did not occur until the second year after planting. Shade treatment had little effect on the time to reach full canopy cover or the duration of full canopy cover, indicating that rhizoma peanut will perform equally in full sun or under 30% shade. Recommended selections for ornamental use based on these variables include ‘Brooksville 67’, ‘Brooksville 68’, EX3, and EX8.

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Rosanna Freyre, Zhanao Deng, Gary W. Knox, Steven Montalvo and Victor Zayas