ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a se... more ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a serious, often undetected pest of Lantana, a landscape plant commonly grown for its heat and drought hardiness across the southern United States. This insect is often responsible for loss of flowering by Lantana plants in late summer and early autumn. Replications of 22 cultivars of Lantana plants in containers were evaluated for resistance to the lantana stick caterpillar in a greenhouse at Dallas, TX. A natural infestation of the pest developed in mid-July and dispersed through all the plantings. Larvae were sampled during autumn 1996. Most larvae (2.4 to 4.1) per plant were on 'Lemon Swirl', 'New Gold', 'Golden King', ISG Red Orange', 'Dallas Red', 'Pink Caprice', 'Gold Mound', and 'Samantha'. No larvae were found on 'Weeping Lavender' or 'White Lightning' and only means of 0.1, 0.3, and 0.3 larva per plant were recorded on 'Imperial Purple', 'Weeping White', and 'Confetti', respectively. Additionally, 0.5 or fewer larva was found per plant of 'Patriot Fire Wagon' and 'Patriot Rainbow'. All four cultivars of L. montevidensis (K. Spreng.) Brig. (mean of 0.1 larva per plant) were very resistant, whereas all cultivars of L. camara L. (except Lemon Drop', mean of 0.8), and all L. hybrida hort were susceptible and exceeded one larva per plant. Cultivars with purple, white, or red/yellow flowers were infested with fewer larvae than were cultivars with gold, red, orange/red, yellow, or bicolors of yellow with another color other than red.
ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a se... more ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a serious, often undetected pest of Lantana, a landscape plant commonly grown for its heat and drought hardiness across the southern United States. This insect is often responsible for loss of flowering by Lantana plants in late summer and early autumn. Replications of 22 cultivars of Lantana plants in containers were evaluated for resistance to the lantana stick caterpillar in a greenhouse at Dallas, TX. A natural infestation of the pest developed in mid-July and dispersed through all the plantings. Larvae were sampled during autumn 1996. Most larvae (2.4 to 4.1) per plant were on 'Lemon Swirl', 'New Gold', 'Golden King', ISG Red Orange', 'Dallas Red', 'Pink Caprice', 'Gold Mound', and 'Samantha'. No larvae were found on 'Weeping Lavender' or 'White Lightning' and only means of 0.1, 0.3, and 0.3 larva per plant were recorded on 'Imperial Purple', 'Weeping White', and 'Confetti', respectively. Additionally, 0.5 or fewer larva was found per plant of 'Patriot Fire Wagon' and 'Patriot Rainbow'. All four cultivars of L. montevidensis (K. Spreng.) Brig. (mean of 0.1 larva per plant) were very resistant, whereas all cultivars of L. camara L. (except Lemon Drop', mean of 0.8), and all L. hybrida hort were susceptible and exceeded one larva per plant. Cultivars with purple, white, or red/yellow flowers were infested with fewer larvae than were cultivars with gold, red, orange/red, yellow, or bicolors of yellow with another color other than red.
Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Tran... more Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Trans-Pecos desert and desert grasslands of Arizona, Texas, and New Mexico. The plant is valued for producing an abundance of distinctive 2.0 cm diameter white flowers on greenish and sparsely leaved stems. Selections of Z. acerosa from West Texas are under evaluation as a water conserving plant species for use in arid landscapes of the Southwest. During April through June, Z. acerosa plants in TAMU, Dallas field plots were observed with small, brown flower spots that enlarged to include whole petals, causing conspicuous flower blighting. Microscopic examination of lesions from infected flower blossoms demonstrated the presence of short beaked, cylindrical spores near the smaller lesions on flower petals. Isolations from symptomatic flower petals consistently yielded cultures of an Alternaria sp. with long chains of conidia. Typical conidia contained 3 to 5 transverse walls and 1 to 2 longitudinal walls and measured 43 μm length by 15 μm width. The fungus was identified as A. alternata (Fries) Keissler consistent with the description in Ellis (1). Pathogenicity tests were conducted on plants maintained on a greenhouse bench by spraying spore suspensions obtained from 16-day-old A. alternata cultures on potato-dextrose agar. Inoculations produced light brown lesions on blossoms typical of field disease symptoms of the disease. This disease is important as a flower blight, however, infections on the leaves are also apparent but limited. Outbreaks of the disease are frequently observed during periods of rainfall during the summer months. This is the first report of Alternaria alternata causing a floral blight on Z. acerosa. References: (1) M. B. Ellis. 1971. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, Surrey, England.
Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Tran... more Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Trans-Pecos desert and desert grasslands of Arizona, Texas, and New Mexico. The plant is valued for producing an abundance of distinctive 2.0 cm diameter white flowers on greenish and sparsely leaved stems. Selections of Z. acerosa from West Texas are under evaluation as a water conserving plant species for use in arid landscapes of the Southwest. During April through June, Z. acerosa plants in TAMU, Dallas field plots were observed with small, brown flower spots that enlarged to include whole petals, causing conspicuous flower blighting. Microscopic examination of lesions from infected flower blossoms demonstrated the presence of short beaked, cylindrical spores near the smaller lesions on flower petals. Isolations from symptomatic flower petals consistently yielded cultures of an Alternaria sp. with long chains of conidia. Typical conidia contained 3 to 5 transverse walls and 1 to 2 longitudinal walls and measured 43 μm length by 15 μm width. The fungus was identified as A. alternata (Fries) Keissler consistent with the description in Ellis (1). Pathogenicity tests were conducted on plants maintained on a greenhouse bench by spraying spore suspensions obtained from 16-day-old A. alternata cultures on potato-dextrose agar. Inoculations produced light brown lesions on blossoms typical of field disease symptoms of the disease. This disease is important as a flower blight, however, infections on the leaves are also apparent but limited. Outbreaks of the disease are frequently observed during periods of rainfall during the summer months. This is the first report of Alternaria alternata causing a floral blight on Z. acerosa. References: (1) M. B. Ellis. 1971. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, Surrey, England.
Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and tem... more Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and temperature treatments. Without scarification, 80% at germination temperatures between 18 and 24°C within seven days. The most rapid germination occurred between 21 and 24°C. At 32°C, total germination was reduced to approximately 2%. At 35°C, germination did not occur. Our data indicate that seeds of L. arboreus must be scarified to obtain high germination percentages and the most rapid germination occurs between 24-29°C.
Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and tem... more Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and temperature treatments. Without scarification, 80% at germination temperatures between 18 and 24°C within seven days. The most rapid germination occurred between 21 and 24°C. At 32°C, total germination was reduced to approximately 2%. At 35°C, germination did not occur. Our data indicate that seeds of L. arboreus must be scarified to obtain high germination percentages and the most rapid germination occurs between 24-29°C.
The University of Arkansas Horticulture Department was charged in 2016 by university administrati... more The University of Arkansas Horticulture Department was charged in 2016 by university administration to develop and implement a student learning outcome (SLO)-based assessment plan. The Horticulture Department curriculum committee was tasked to develop such a plan. Various models were considered, but ultimately a modified plan based on the work of M.P. Pritts and T. Park was adopted. Adjustments were based on student population size and particular requirements that had to be integrated with the university-mandated SLO goals and objectives. Two phases of a student’s academic career were chosen to access: an incoming freshman or transfer phase and a late-term or degree completion phase. Specific learning outcomes and goals were identified as well as courses and activities that would reasonably be measured while meeting university requirements. Data collection on entering freshmen and transfer students started in Fall 2018. The full impact of the implemented plan will not be known until...
The University of Arkansas Horticulture Department was charged in 2016 by university administrati... more The University of Arkansas Horticulture Department was charged in 2016 by university administration to develop and implement a student learning outcome (SLO)-based assessment plan. The Horticulture Department curriculum committee was tasked to develop such a plan. Various models were considered, but ultimately a modified plan based on the work of M.P. Pritts and T. Park was adopted. Adjustments were based on student population size and particular requirements that had to be integrated with the university-mandated SLO goals and objectives. Two phases of a student’s academic career were chosen to access: an incoming freshman or transfer phase and a late-term or degree completion phase. Specific learning outcomes and goals were identified as well as courses and activities that would reasonably be measured while meeting university requirements. Data collection on entering freshmen and transfer students started in Fall 2018. The full impact of the implemented plan will not be known until...
A study was conducted to explore how different mulches affect water use of landscape plants. Plot... more A study was conducted to explore how different mulches affect water use of landscape plants. Plots 4.9 m × 7.3 m, were covered with 5cm pine bark, cypress, white rock, or clay aggregate. 3 potted plants of Ligustrum japonicum (wax-leaf ligustrum) and Photinia × fraseri (red tip photinia) were placed in each plot so that the top of each pot was at ground level. 1 plant of each species was planted directly into each plot. Water loss was measured on a daily basis, both gravimetrically and using heat balance stem flow gauges, during both the 1992 and 1993 growing seasons. Stomatal conductance was measured periodically during each growing season. Surface, air, and soil temperatures at two depths were recorded. During 1992, pine bark mulched plants consistently used more water than the other treatments, as opposed to summer 1993 when the most water was used by plants over white rock. Surface temperatures of pine bark, cypress and clay aggregates were higher than those of white rock both y...
A study was conducted to explore how different mulches affect water use of landscape plants. Plot... more A study was conducted to explore how different mulches affect water use of landscape plants. Plots 4.9 m × 7.3 m, were covered with 5cm pine bark, cypress, white rock, or clay aggregate. 3 potted plants of Ligustrum japonicum (wax-leaf ligustrum) and Photinia × fraseri (red tip photinia) were placed in each plot so that the top of each pot was at ground level. 1 plant of each species was planted directly into each plot. Water loss was measured on a daily basis, both gravimetrically and using heat balance stem flow gauges, during both the 1992 and 1993 growing seasons. Stomatal conductance was measured periodically during each growing season. Surface, air, and soil temperatures at two depths were recorded. During 1992, pine bark mulched plants consistently used more water than the other treatments, as opposed to summer 1993 when the most water was used by plants over white rock. Surface temperatures of pine bark, cypress and clay aggregates were higher than those of white rock both y...
Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-... more Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-October. Plants (1 year old, 3.8 liter) were obtained from a local nursery and transplanted in May into 18.9-liter Iysimeter pots containing either clay loam or bluepoint sand. Controls were lysimeter pots containing each soil type but without plants. Irrigation was applied at two rates, approximately field (pot) capacity and 50% of that amount. Irrigation frequency was determined by visual inspection of the plants and was held constant for both irrigation rates in a given soil type. Frequency ranged from 2 to 3 days for the sand and 2 to 5 days for the clay loam. Water loss was determined every 24 h. Plant water loss was higher at the higher irrigation rate. Decreasing irrigation rate by 50% resulted in a 20% to 40% reduction in plant water use in clay loam and a 15% to 30% reduction in sand without affecting plant quality. Plant water loss in the sandy soil was ≈50% greater than in cla...
Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-... more Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-October. Plants (1 year old, 3.8 liter) were obtained from a local nursery and transplanted in May into 18.9-liter Iysimeter pots containing either clay loam or bluepoint sand. Controls were lysimeter pots containing each soil type but without plants. Irrigation was applied at two rates, approximately field (pot) capacity and 50% of that amount. Irrigation frequency was determined by visual inspection of the plants and was held constant for both irrigation rates in a given soil type. Frequency ranged from 2 to 3 days for the sand and 2 to 5 days for the clay loam. Water loss was determined every 24 h. Plant water loss was higher at the higher irrigation rate. Decreasing irrigation rate by 50% resulted in a 20% to 40% reduction in plant water use in clay loam and a 15% to 30% reduction in sand without affecting plant quality. Plant water loss in the sandy soil was ≈50% greater than in cla...
The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flow... more The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flower, but postharvest life is limited by ethylene sensitivity. The authors studied the effects of 160 nL·L−1 1-methylcyclopropene (1-MCP) with 0 to 6 days exposure to a 50-μm vase solution of ethephon [(2-chloroethyl) phosphonic acid, CEPA] on raceme postharvest quality indices and mature flower cell membrane permeability. With no CEPA, 1-MCP delayed postharvest losses in fresh weight and mature flower retention, and extended vase life longevity (VLL) by 1 to 4 days relative to a non-1-MCP control. With 2 days or more of CEPA, 1-MCP deferred raceme fresh weight loss and the abscission of both mature and newly opened flowers from 3 days to 5 days. There was a relatively strong protective effect of 1-MCP on raceme fresh weight, flower retention, and newly opening flowers in the presence of CEPA compared with the absence of CEPA. The greatest raceme VLL (7.2 days) was obtained for 1-MCP-treat...
The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flow... more The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flower, but postharvest life is limited by ethylene sensitivity. The authors studied the effects of 160 nL·L−1 1-methylcyclopropene (1-MCP) with 0 to 6 days exposure to a 50-μm vase solution of ethephon [(2-chloroethyl) phosphonic acid, CEPA] on raceme postharvest quality indices and mature flower cell membrane permeability. With no CEPA, 1-MCP delayed postharvest losses in fresh weight and mature flower retention, and extended vase life longevity (VLL) by 1 to 4 days relative to a non-1-MCP control. With 2 days or more of CEPA, 1-MCP deferred raceme fresh weight loss and the abscission of both mature and newly opened flowers from 3 days to 5 days. There was a relatively strong protective effect of 1-MCP on raceme fresh weight, flower retention, and newly opening flowers in the presence of CEPA compared with the absence of CEPA. The greatest raceme VLL (7.2 days) was obtained for 1-MCP-treat...
ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a se... more ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a serious, often undetected pest of Lantana, a landscape plant commonly grown for its heat and drought hardiness across the southern United States. This insect is often responsible for loss of flowering by Lantana plants in late summer and early autumn. Replications of 22 cultivars of Lantana plants in containers were evaluated for resistance to the lantana stick caterpillar in a greenhouse at Dallas, TX. A natural infestation of the pest developed in mid-July and dispersed through all the plantings. Larvae were sampled during autumn 1996. Most larvae (2.4 to 4.1) per plant were on 'Lemon Swirl', 'New Gold', 'Golden King', ISG Red Orange', 'Dallas Red', 'Pink Caprice', 'Gold Mound', and 'Samantha'. No larvae were found on 'Weeping Lavender' or 'White Lightning' and only means of 0.1, 0.3, and 0.3 larva per plant were recorded on 'Imperial Purple', 'Weeping White', and 'Confetti', respectively. Additionally, 0.5 or fewer larva was found per plant of 'Patriot Fire Wagon' and 'Patriot Rainbow'. All four cultivars of L. montevidensis (K. Spreng.) Brig. (mean of 0.1 larva per plant) were very resistant, whereas all cultivars of L. camara L. (except Lemon Drop', mean of 0.8), and all L. hybrida hort were susceptible and exceeded one larva per plant. Cultivars with purple, white, or red/yellow flowers were infested with fewer larvae than were cultivars with gold, red, orange/red, yellow, or bicolors of yellow with another color other than red.
ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a se... more ABSTRACT Lantana stick caterpillar, Neogalea sunia (Guenee) (Lepidoptera: Noctuidae), can be a serious, often undetected pest of Lantana, a landscape plant commonly grown for its heat and drought hardiness across the southern United States. This insect is often responsible for loss of flowering by Lantana plants in late summer and early autumn. Replications of 22 cultivars of Lantana plants in containers were evaluated for resistance to the lantana stick caterpillar in a greenhouse at Dallas, TX. A natural infestation of the pest developed in mid-July and dispersed through all the plantings. Larvae were sampled during autumn 1996. Most larvae (2.4 to 4.1) per plant were on 'Lemon Swirl', 'New Gold', 'Golden King', ISG Red Orange', 'Dallas Red', 'Pink Caprice', 'Gold Mound', and 'Samantha'. No larvae were found on 'Weeping Lavender' or 'White Lightning' and only means of 0.1, 0.3, and 0.3 larva per plant were recorded on 'Imperial Purple', 'Weeping White', and 'Confetti', respectively. Additionally, 0.5 or fewer larva was found per plant of 'Patriot Fire Wagon' and 'Patriot Rainbow'. All four cultivars of L. montevidensis (K. Spreng.) Brig. (mean of 0.1 larva per plant) were very resistant, whereas all cultivars of L. camara L. (except Lemon Drop', mean of 0.8), and all L. hybrida hort were susceptible and exceeded one larva per plant. Cultivars with purple, white, or red/yellow flowers were infested with fewer larvae than were cultivars with gold, red, orange/red, yellow, or bicolors of yellow with another color other than red.
Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Tran... more Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Trans-Pecos desert and desert grasslands of Arizona, Texas, and New Mexico. The plant is valued for producing an abundance of distinctive 2.0 cm diameter white flowers on greenish and sparsely leaved stems. Selections of Z. acerosa from West Texas are under evaluation as a water conserving plant species for use in arid landscapes of the Southwest. During April through June, Z. acerosa plants in TAMU, Dallas field plots were observed with small, brown flower spots that enlarged to include whole petals, causing conspicuous flower blighting. Microscopic examination of lesions from infected flower blossoms demonstrated the presence of short beaked, cylindrical spores near the smaller lesions on flower petals. Isolations from symptomatic flower petals consistently yielded cultures of an Alternaria sp. with long chains of conidia. Typical conidia contained 3 to 5 transverse walls and 1 to 2 longitudinal walls and measured 43 μm length by 15 μm width. The fungus was identified as A. alternata (Fries) Keissler consistent with the description in Ellis (1). Pathogenicity tests were conducted on plants maintained on a greenhouse bench by spraying spore suspensions obtained from 16-day-old A. alternata cultures on potato-dextrose agar. Inoculations produced light brown lesions on blossoms typical of field disease symptoms of the disease. This disease is important as a flower blight, however, infections on the leaves are also apparent but limited. Outbreaks of the disease are frequently observed during periods of rainfall during the summer months. This is the first report of Alternaria alternata causing a floral blight on Z. acerosa. References: (1) M. B. Ellis. 1971. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, Surrey, England.
Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Tran... more Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Trans-Pecos desert and desert grasslands of Arizona, Texas, and New Mexico. The plant is valued for producing an abundance of distinctive 2.0 cm diameter white flowers on greenish and sparsely leaved stems. Selections of Z. acerosa from West Texas are under evaluation as a water conserving plant species for use in arid landscapes of the Southwest. During April through June, Z. acerosa plants in TAMU, Dallas field plots were observed with small, brown flower spots that enlarged to include whole petals, causing conspicuous flower blighting. Microscopic examination of lesions from infected flower blossoms demonstrated the presence of short beaked, cylindrical spores near the smaller lesions on flower petals. Isolations from symptomatic flower petals consistently yielded cultures of an Alternaria sp. with long chains of conidia. Typical conidia contained 3 to 5 transverse walls and 1 to 2 longitudinal walls and measured 43 μm length by 15 μm width. The fungus was identified as A. alternata (Fries) Keissler consistent with the description in Ellis (1). Pathogenicity tests were conducted on plants maintained on a greenhouse bench by spraying spore suspensions obtained from 16-day-old A. alternata cultures on potato-dextrose agar. Inoculations produced light brown lesions on blossoms typical of field disease symptoms of the disease. This disease is important as a flower blight, however, infections on the leaves are also apparent but limited. Outbreaks of the disease are frequently observed during periods of rainfall during the summer months. This is the first report of Alternaria alternata causing a floral blight on Z. acerosa. References: (1) M. B. Ellis. 1971. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, Surrey, England.
Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and tem... more Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and temperature treatments. Without scarification, 80% at germination temperatures between 18 and 24°C within seven days. The most rapid germination occurred between 21 and 24°C. At 32°C, total germination was reduced to approximately 2%. At 35°C, germination did not occur. Our data indicate that seeds of L. arboreus must be scarified to obtain high germination percentages and the most rapid germination occurs between 24-29°C.
Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and tem... more Seeds of Lupinus arboreus Sims (bush lupine) were subjected to a variety of scarification and temperature treatments. Without scarification, 80% at germination temperatures between 18 and 24°C within seven days. The most rapid germination occurred between 21 and 24°C. At 32°C, total germination was reduced to approximately 2%. At 35°C, germination did not occur. Our data indicate that seeds of L. arboreus must be scarified to obtain high germination percentages and the most rapid germination occurs between 24-29°C.
The University of Arkansas Horticulture Department was charged in 2016 by university administrati... more The University of Arkansas Horticulture Department was charged in 2016 by university administration to develop and implement a student learning outcome (SLO)-based assessment plan. The Horticulture Department curriculum committee was tasked to develop such a plan. Various models were considered, but ultimately a modified plan based on the work of M.P. Pritts and T. Park was adopted. Adjustments were based on student population size and particular requirements that had to be integrated with the university-mandated SLO goals and objectives. Two phases of a student’s academic career were chosen to access: an incoming freshman or transfer phase and a late-term or degree completion phase. Specific learning outcomes and goals were identified as well as courses and activities that would reasonably be measured while meeting university requirements. Data collection on entering freshmen and transfer students started in Fall 2018. The full impact of the implemented plan will not be known until...
The University of Arkansas Horticulture Department was charged in 2016 by university administrati... more The University of Arkansas Horticulture Department was charged in 2016 by university administration to develop and implement a student learning outcome (SLO)-based assessment plan. The Horticulture Department curriculum committee was tasked to develop such a plan. Various models were considered, but ultimately a modified plan based on the work of M.P. Pritts and T. Park was adopted. Adjustments were based on student population size and particular requirements that had to be integrated with the university-mandated SLO goals and objectives. Two phases of a student’s academic career were chosen to access: an incoming freshman or transfer phase and a late-term or degree completion phase. Specific learning outcomes and goals were identified as well as courses and activities that would reasonably be measured while meeting university requirements. Data collection on entering freshmen and transfer students started in Fall 2018. The full impact of the implemented plan will not be known until...
A study was conducted to explore how different mulches affect water use of landscape plants. Plot... more A study was conducted to explore how different mulches affect water use of landscape plants. Plots 4.9 m × 7.3 m, were covered with 5cm pine bark, cypress, white rock, or clay aggregate. 3 potted plants of Ligustrum japonicum (wax-leaf ligustrum) and Photinia × fraseri (red tip photinia) were placed in each plot so that the top of each pot was at ground level. 1 plant of each species was planted directly into each plot. Water loss was measured on a daily basis, both gravimetrically and using heat balance stem flow gauges, during both the 1992 and 1993 growing seasons. Stomatal conductance was measured periodically during each growing season. Surface, air, and soil temperatures at two depths were recorded. During 1992, pine bark mulched plants consistently used more water than the other treatments, as opposed to summer 1993 when the most water was used by plants over white rock. Surface temperatures of pine bark, cypress and clay aggregates were higher than those of white rock both y...
A study was conducted to explore how different mulches affect water use of landscape plants. Plot... more A study was conducted to explore how different mulches affect water use of landscape plants. Plots 4.9 m × 7.3 m, were covered with 5cm pine bark, cypress, white rock, or clay aggregate. 3 potted plants of Ligustrum japonicum (wax-leaf ligustrum) and Photinia × fraseri (red tip photinia) were placed in each plot so that the top of each pot was at ground level. 1 plant of each species was planted directly into each plot. Water loss was measured on a daily basis, both gravimetrically and using heat balance stem flow gauges, during both the 1992 and 1993 growing seasons. Stomatal conductance was measured periodically during each growing season. Surface, air, and soil temperatures at two depths were recorded. During 1992, pine bark mulched plants consistently used more water than the other treatments, as opposed to summer 1993 when the most water was used by plants over white rock. Surface temperatures of pine bark, cypress and clay aggregates were higher than those of white rock both y...
Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-... more Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-October. Plants (1 year old, 3.8 liter) were obtained from a local nursery and transplanted in May into 18.9-liter Iysimeter pots containing either clay loam or bluepoint sand. Controls were lysimeter pots containing each soil type but without plants. Irrigation was applied at two rates, approximately field (pot) capacity and 50% of that amount. Irrigation frequency was determined by visual inspection of the plants and was held constant for both irrigation rates in a given soil type. Frequency ranged from 2 to 3 days for the sand and 2 to 5 days for the clay loam. Water loss was determined every 24 h. Plant water loss was higher at the higher irrigation rate. Decreasing irrigation rate by 50% resulted in a 20% to 40% reduction in plant water use in clay loam and a 15% to 30% reduction in sand without affecting plant quality. Plant water loss in the sandy soil was ≈50% greater than in cla...
Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-... more Water loss of Nerium oleander growing in two soil types was determined from mid-June through mid-October. Plants (1 year old, 3.8 liter) were obtained from a local nursery and transplanted in May into 18.9-liter Iysimeter pots containing either clay loam or bluepoint sand. Controls were lysimeter pots containing each soil type but without plants. Irrigation was applied at two rates, approximately field (pot) capacity and 50% of that amount. Irrigation frequency was determined by visual inspection of the plants and was held constant for both irrigation rates in a given soil type. Frequency ranged from 2 to 3 days for the sand and 2 to 5 days for the clay loam. Water loss was determined every 24 h. Plant water loss was higher at the higher irrigation rate. Decreasing irrigation rate by 50% resulted in a 20% to 40% reduction in plant water use in clay loam and a 15% to 30% reduction in sand without affecting plant quality. Plant water loss in the sandy soil was ≈50% greater than in cla...
The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flow... more The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flower, but postharvest life is limited by ethylene sensitivity. The authors studied the effects of 160 nL·L−1 1-methylcyclopropene (1-MCP) with 0 to 6 days exposure to a 50-μm vase solution of ethephon [(2-chloroethyl) phosphonic acid, CEPA] on raceme postharvest quality indices and mature flower cell membrane permeability. With no CEPA, 1-MCP delayed postharvest losses in fresh weight and mature flower retention, and extended vase life longevity (VLL) by 1 to 4 days relative to a non-1-MCP control. With 2 days or more of CEPA, 1-MCP deferred raceme fresh weight loss and the abscission of both mature and newly opened flowers from 3 days to 5 days. There was a relatively strong protective effect of 1-MCP on raceme fresh weight, flower retention, and newly opening flowers in the presence of CEPA compared with the absence of CEPA. The greatest raceme VLL (7.2 days) was obtained for 1-MCP-treat...
The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flow... more The raceme of Lupinus havardii Wats. (Big Bend bluebonnet) is a new greenhouse specialty cut flower, but postharvest life is limited by ethylene sensitivity. The authors studied the effects of 160 nL·L−1 1-methylcyclopropene (1-MCP) with 0 to 6 days exposure to a 50-μm vase solution of ethephon [(2-chloroethyl) phosphonic acid, CEPA] on raceme postharvest quality indices and mature flower cell membrane permeability. With no CEPA, 1-MCP delayed postharvest losses in fresh weight and mature flower retention, and extended vase life longevity (VLL) by 1 to 4 days relative to a non-1-MCP control. With 2 days or more of CEPA, 1-MCP deferred raceme fresh weight loss and the abscission of both mature and newly opened flowers from 3 days to 5 days. There was a relatively strong protective effect of 1-MCP on raceme fresh weight, flower retention, and newly opening flowers in the presence of CEPA compared with the absence of CEPA. The greatest raceme VLL (7.2 days) was obtained for 1-MCP-treat...
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