bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Preemergence Herbicides on Hosta and Daylily
Authors: Whitwell Ted , Kelly John
Published: August 2020

Thirteen preemergence herbicides were evaluated for phytotoxicity to container grown hosta (Hosta spp. Tratt. ‘Hyacinthina’) and daylily (Hemerocallis spp. L. ‘Sammy Russell’). Severe injury (28 to 55%) was observed from Ronstar (oxadiazon) and Goal (oxyfluorfen) for both species. The other herbicides did not cause visual injury. Three herbicides, Surflan (oryzalin), Endurance (prodiamine) and Pennant (metolachlor), were selected to investigate plant tolerance in field plantings at 1.1, 2.2, and 4.5 kg/ha (1, 2, and 4 lb/A). None of these herbicides caused visual injury or reduced shoot or root weight for 60 or 90 days after treatment. Daylily flower number was not affected by any of the herbicide treatments.
Nitrate in Runoff Water from Container Grown Juniper and Alberta Spruce Under Different Irrigation and N Fertilization Regimes
Authors: Rathier Thomas M. , Frink Charles R.
Published: August 2020

Juniperus horizontalis Moench ‘Plumosa Compacta Youngstown’ (compact Andorra juniper) and Picea glauca Moench (Voss) ‘Conica’ (dwarf Alberta spruce) were grown for one season in 2.2 1 (#1) nursery containers in a potting medium containing composted hardwood bark, sphagnum peat moss and sand (1:1:1 by vol). The containers were placed over lysimeters permitting continuous collection and measurement of water passing through and around the containers. Slow release or soluble N was applied at an annual rate of 1.6 g of N per pot. Containers were irrigated by either trickle or overhead methods and water volumes were recorded. Subsamples of leachate were collected and analyzed for nitrate. Much less nitrate was leached by the trickle than by the overhead irrigation. Although slow release N sources lost considerably less nitrate in runoff water, there is still sufficient nitrate lost by these sources to pollute ground water unless annual fertilizer needs are supplied by split applications. Depending on sources, 58–80% of the N applied as slow release fertilizers was not recovered in either the plant or runoff water.
Control of Prostrate Spurge (Euphorbia humistrata) and Large Crabgrass (Digitaria sanquinalas) in Container Grown Ilex crenata ‘Compacta’ With Herbicide Combinations
Authors: Whitwell Ted , Kalmowitz Kathie
Published: August 2020

Granular herbicide combinations were evaluated for longevity of prostrate spurge (Euphorbia humistrata Engelm.ex.Gray) and large crabgrass (Digitaria sanguinalis L.) control. Rout (oxytluorfen + oryzalin), Ornamental Herbicide 2 (oxytluorfen + pendimethalin), Ronstar plus Modown (oxadiazon + bifenox) and Ronstar (oxadiazon) were applied at labeled rates and twice labeled rate in container grown Compact Japanese Holly (Ilex crenata ‘Compacta’). Weeds were reseeded each month but herbicides were not reapplied. The normal use rate controlled both weeds during the first 30 days after treatment (DAT) while twice this rate controlled the weed species at 60 DAT. No herbicide treatment effectively (>80%) controlled prostrate spurge 90 DAT. The high rate of Rout controlled (>80%) crabgrass at 90 DAT. Weed numbers and above ground biomass retlected visual control ratings. Compact Japanese Holly was not injured by any treatment.
Weed Control with Gallery and Other Herbicides in Field-Grown Nursery Crops
Authors: Gilliam C.H. , Wehtje G. , Eason J.E. , Hicks T.V. , Fare D.C.
Published: August 2020

Selected herbicides were evaluated for weed control in a two-year field test with boxwood, holly, viburnum and nandina. Gallery (isoxaben), when applied alone, generally provided inferior grass control during year one compared to Surflan (oryzalin). Surflan in combination with Gallery at 3.4 + 1.1 kg/ha (3.0 + 1.0 lb/A) provided weed control similar to that obtained with traditional herbicide programs of Surflan in combination with Princep (simazine) and/or Goal (oxyfluorfen). Plant size of four woody plant species, treated twice annually with Surflan + Gallery over a two year period, was statistically equivalent to the maximum plant size obtained with any other treatment.
Control of Phytophthora Root Rot of Rhododendron chapmanii A. Gray with Subdue
Authors: Benson D. M. , Blazich Frank A.
Published: August 2020

Rooted cuttings of Chapman's rhododendron (Rhododendron chapmanii) in soilless medium were challenged with inoculum of the soi1borne fungus, Phytophthora cinnamomi (Rands). A portion of the plants received a soil drench of Subdue 2EC (metalaxyl) at 0.16 ml/L (2.0 oz/100 gal) at 2 month intervals. Chapman's rhododendron was highly susceptible to P. cinnamomi, but five of six plants treated with Subdue did not develop symptoms of Phytophthora root rot. In the one plant which developed root rot symptoms, P. cinnamomi was recovered in culture.
Influence of Phosphorus on Nitrogen Fertilizer Requirement of Melampodium leucanthum (Blackfoot Daisy) Grown in Perlite-Vermiculite Medium
Authors: Hipp Billy W. , Simpson Benny J. , Graff Paul S.
Published: August 2020

We determined the influence of N and P fertilizers on growth and tissue N concentration of container grown blackfoot daisy (Melampodium leucanthum Ton. & Gray), a resource-efficient native landscape herbaceous perennial for the southwestern United States. Regression equations derived from the data indicated that maximum growth could be obtained by application of 166 mg N/liter (ppm) in irrigation water if 30 mg P/liter were also applied. However, near maximum growth was obtained with 100 mg N/liter at the 30 mg P/liter level. Fifteen mg P/liter in irrigation water were not adequate for maximum growth. Tissue nitrogen concentrations in whole plants should be > 1.7% for growth not to be limited by N.
Plant Form In Relation To Root Spread
Authors: Gilman Edward F.
Published: August 2020

Four Juniperus chinensis cultivars, ‘Torulosa’, ‘Sylvestris’, ‘Pfitzeriana’ and ‘Hetzii’ had mean and maximum root spreads of 1.6m (4.8 ft) and 2.2 m (6.6 ft) resp, 12 months after planting. Despite large differences in plant form, root spread on all four cultivars was equal. The columnar cultivar ‘Torulosa’ had significantly less root length within the drip-line than the more spreading cultivars ‘Pfitzeriana’ and ‘Hetzii’. Percentage of total root length within the dripline was correlated (r= −.72) with the ratio of plant height to spread.
Direct-Seeded Kentucky Coffeetree Seed Tolerance to Preemergent Herbicides
Authors: Long C.E. , Geyer W.A.
Published: August 2020

Various soil types (loamy and sandy soils) were seeded with Kentucky coffeetree, treated with preemergent herbicides and grown in the greenhouse to determine their effect on seedling survival and growth. Tested were Lasso (alachlor) at 2.2 (2.0), Tenoran 50W (chloroxuron) at 2.2 (2.0), Dacthal (DCPA) at 11.2 (10.0), Eptam (EPTC) at 4.5 (4.0), Devrinol (napropamide) at 1.1 (1.0), Ronstar (oxadiazon) at 4.5 (4.0) and Tolban 4E (profluralin) at 0.6 (0.5) kg ai/ha (lb ai/a). All treatments tested allowed acceptable survival (82%) and height or dry weight growth.
Weed Control with Landscape Fabrics
Authors: Derr Jeffrey F. , Appleton Bonnie Lee
Published: August 2020

Six polypropylene landscape fabrics were compared with black plastic and preemergence herbicides for weed control. Large crabgrass [Digitaria sanguinalis (L.) Scop.] shoots and roots and yellow nutsedge (Cyperus esculentus L.) shoots penetrated all of the fabrics tested and developed into large plants. In greenhouse studies, black plastic plus mulch, and pennant (metolachlor) [2-chloro-N-(2ethyl-6-methylphenyl)-N-(methoxy-1-methylethyl)acetamide] at 4.5 kg ai/ha (4.0 lb/A) plus mulch provided equal, or greater control of large crabgrass than the landscape fabrics. In the field study, more time was required to hand-weed landscape fabrics covered with mulch than uncovered fabrics. When covered with mulch, hand-weeding time and weed shoot fresh weights were similar for black plastic, surflan (oryzalin) [4-(dipropylamino)-3,5-dinitrobenzenesulfonamide] at 2.2 kg/ha (2.0 lb/A), and the landscape fabrics.
Growth and Quality of Colorado Spruce Transplanted during the Spring Growth Flush
Authors: Tripepi Robert R. , Carter Joseph E.
Published: August 2020

Conifers transplanted during the spring growth flush can be injured or even killed due to severe root losses. In this study, 3-2 Colorado spruce (Picea pungens Engelm.) were dug as balled and burlapped or bare-root plants in late April and May. Bare-root plants were treated with distilled water, absolute (100%) ethanol, or 1000 mg/L of indole-3-butyric acid (lBA) in 20% or absolute ethanol. Less than 2% of all trees transplanted in April died, whereas 80 and 100% of the plants dug in May and treated with absolute ethanol or IBA in absolute ethanol died. Terminal growth on balled and burlapped plants moved in April was 60% greater than that on bare-root spruces treated with water, the second best treatment. Terminal shoots expanded the most between five and seven weeks after bud break for plants transplanted in April, and balled and burlapped spruces grew the most. Visual ratings of bare-root plants treated with absolute ethanol alone or combined with IBA was significantly poorer than that of spruces receiving the other treatments in both months. This study demonstrated that 3-2 Colorado spruce can be successfully transplanted during its spring growth flush regardless of the digging method used.
Influence of Light and Temperature on Seed Germination of Mountain Laurel
Authors: Malek Asiah A. , Blazich Frank A. , Warren Stuart L. , Shelton James E.
Published: August 2020

Seeds of mountain laurel (Kalmia latifolia L.) were germinated at 2.5°C (77°F) and 25°/15°C (77°/59°F) with daily photoperiods of 0, ½, ½ twice daily, 1, 2, 4, 8, 12, and 24 hr. Seeds exhibited an obilgate light requirement. At 25°C (77°F), increasing photoperiods increased germination with maximum germination (90%) occuring by day 18 under continuous illumination. The alternating temperature of 25°/15°C (77°/59°F) enhanced germination when light was limiting. At this temperature, maximum germination of 86 to 87% was reached by day 24 for photoperiods ≥ 8 hr.
Response of Nine Herbaceous Flowering Perennials to Selected Herbicides
Authors: Skroch W.A. , Catanzaro C.J. , Yonce M.R.
Published: August 2020

Nine herbicides registered for use on turf and ornamentals were applied semiannually for 2 years to 9 species of field grown herbaceous flowering perennials. The herbicides used were Balan (benefin), Betasan (bensulide), Dacthal (DCPA), Devrinol (napropamide), Fusilade (fluazifop), Ornamental Herbicide 2 (oxyfluorfen + pendimethalin), Pennant (metolachlor), Poast (sethoxydim), and Ronstar (oxadiazon). The perennials included fernleaf yarrow, shasta daisy, coreopsis, dianthus, daylily, candytuft, red hot poker, statice, and phlox. Betasan produced no visual phytotoxicity. All other treatments, excluding Ornamental Herbicide 2 (OH-2), caused less than 20% injury to all species tested. OH-2 caused 40%, 39%, and 30% injury to daylily, yarrow, and red hot poker, respectively. Economically tolerable (less than 25%) injury was exhibited by phlox and shasta daisy treated with OH-2, by daylily treated with Pennant, and by phlox treated with Ronstar. OH-2 increased flowering of coreopsis and statice by 97% and 235%, respectively, while it reduced plant area of phlox by 53% and flowering of phlox by 34%. Both Pennant and OH-2 reduced flowering of dianthus by nearly 30%.
Storage Molds of Herbaceous Perennials
Authors: Hanchek A.M. , Everts K. , Maqbool M. , Cameron A.C.
Published: August 2020

Fungi were subcultured and identified to genera from 24 species of bare-root herbaceous perennials held in commercial cold storage chambers. Ten genera dominated the cultures. Although no pathogenicity tests were conducted, most genera were usually considered to be saprophytes or opportunistic pathogens which often infect previously damaged tissue. Other species of perrennials were harvested from commercial fields and given a Benlate dip fungicide treatment prior to storage. After six months, crowns were removed, rated for mold development, potted, and evaluated for quality of regrowth. Surface molds were generally suppressed by Benlate (Benomyl 50WP), but regrowth was rarely improved and often reduced. Use of fungicides to improve cosmetic appearance of stored herbaceous perennials is not recommended on the basis of these results.
Chilling Units Used to Determine Rooting of Stem Cuttings of Junipers
Authors: Major John E. , Grossnickle Steven C.
Published: August 2020

Stem cuttings from 10 juniper cultivars, representing 5 taxa of juniper (Juniperus chinensis L. ‘Pfitzer Aurea’; J. horizontalis Moench ‘Bar Harbor’, ‘Prince of Wales’, ‘Wiltoni’, ‘Youngstown’; J. procumbens Endl. ‘Green Mound’; J. sabina L. ‘Broadmoor’, ‘Buffalo’, ‘Tamariscifolia’ and; J. scopulorium Sarg. ‘Wichita Blue’) were inserted into rooting beds twice monthly from October 15, 1986 to February 28, 1987. During this time period, air temperature was monitored continuously 1 m (39 in) above the stock plants and seasonal chilling units (i.e., hours at ≤55°C (41°F)) were determined. Chilling units of the donor stock plants affected the percent rooting of most juniper cultivars. Data suggest that the optimum rooting period of most cultivars of juniper can be determined by their chilling units.
Feasibility of Adding Surfactants to Slow-Release Herbicide Tablets for Container-Grown Landscape Plants
Authors: Horowitz Menashe , Smith Elton M. , Gorski Stanley F.
Published: August 2020

Slow-release tablets made of dicalcium phosphate containing a herbicide and a surfactant were evaluated for weed growth. The addition of 1-2% surfactant to herbicides having a very low water solubility, such as Gallery (isoxaben), Surflan (oryzalin), Ronstar (oxadiazon), and Goal (oxyfluorfen), and for comparison, to Dual (metolachlor), markedly enhanced the release of herbicide and enlarged the area of weed inhibition. The surfactants that produced the best results were Triton X-100 and X-77. Tablets placed on the surface of containers filled with Metro Mix 350 or a pine bark-peat moss-sand medium, under intermittent mist in the greenhouse, or under sprinklers outdoors, produced up to 15 cm (6 in) diameter circular areas of weed control, around a single tablet. Initial release of herbicide from tablets was rapid upon exposure to moisture and the area of activity became close to maximum within a few days after placing the tablet on the soil surface. Tablets placed on surface produced larger areas of activity than when buried. The tablets retained their shape after 3 months of outdoor exposure.
Response of Interveinally Chlorotic Red Maple Trees Treated with Medicaps or by Soil Acidification
Authors: Steven Messenger A. , Hruby Brett A.
Published: August 2020

Four replicates of 6 treatments were imposed on a nursery block of interveinally chlorotic red maples (Acer rubrum ‘Red Sundet’ L.) when they were 5 years-old.

Throughout 2 growing seasons of foliar nutrient monitoring, the degree of chlorosis was more closely correlated with leaf concentrations of P and K (positive) than with Mn (negative).

Soil treatments which included subsoil acidification (H2SO4 + MnSO4) were most effective in re-greening the trees and in increasing leaf Mn concentrations, height and diameter growth, and red fall color development. Mn-Medicaps were equally effective as the above treatments in decreasing leaf P and K concentrations and increasing shoot elongation rates. Surface soil acidification alone resulted in either negative or no effects on the health-related parameters measured.
A Computerized Spreadsheet Program for Estimating Costs and Returns of Selected Field-Grown Nursery Stock
Authors: Johnson Larry A. , Tilt Kenneth M.
Published: August 2020

A computerized, menu-driven spreadsheet program was developed to assist nursery producers and other nursery professionals with generating customized nursery budgets for field-grown nursery stock and Christmas trees. The compiled spreadsheet is a “stand alone” program with its financial models based on enterprise budgets taken from extension publications. The program enables the user to estimate production cost and potential profit of an existing or prospective crop. Advantages of the program include the user modifying existing data bases rather than entering all relevant information. Users of the program can also evaluate risk parameters of a decision through the “what-if” capabilities of the spreadsheet
Effect of Trickle Irrigation, Nitrogen Rate, and Method of Application on Field-grown ‘Compacta’ Japanese Holly
Authors: Eakes D.J. , Gilliam C.H. , Ponder H.G. , Evans C.E. , Marini M.E.
Published: August 2020

Three methods of N application and 4 N rates of 34, 67, 134, and 268 kg/ha (30,60 120, and 240 lbs/A) were evaluated on field-grown ‘Compacta’ Japanese holly (Ilex crenata Thunb. ‘Compacta’). Fertilizer application methods consisted of NH4NO3 broadcast over trickle irrigated and non-irrigated plants, and injection of NH4NO3 through the trickle irrigation system. Irrigation regardless of whether N was surface applied or injected through the system, increased root and shoot dry weights, plant size, visual ratings, and percent survival. Irrigated plants had a more fibrous root system. N rate had no affect on root or shoot dry weights, root distribution, visual ratings, or percent survival.
Effectiveness of Alternative Advertising and Promotional Media Vehicles in Garden Center Advertising
Authors: Kelly Horace O.
Published: August 2020

These data, analyzed by different size population centers, show that there is a relationship between the effectiveness of different media vehicles and the size of the population center in which a garden center is located. In large metro areas (500K +), customer mailings, poster advertising specials, and radio are most effective; in small metro locations (lOO–499K), the most effective vehicles are customer mailings, poster advertising specials, posters in the store, and radio; in large cities/towns (50–99K), the optimum choices are posters in the store, poster advertising specials, neighborhood newspapers, customer mailings, and radio; in small cities/towns (−50K), the best media vehicles are posters in the store and neighborhood newspapers.
Turgor Maintenance in Rosa rugosa Grown at Three Levels of Nitrogen and Subjected to Drought
Authors: Augé R.M. , Stodola A.J.W. , Gealy D.M.
Published: August 2020

The influence of N fertilization on turgor maintenance was determined in leaves from well-watered and droughted Rosa rugosa L. Plants were fertilized for 60 days with a complete fertilizer with N at levels of 0, 200 or 500 ppm and then subjected to several drought cycles for 22 days. Plants receivmg no N were stunted and chlorotic, but had the greatest full saturation turgor pressure and symplastic osmolality, and the lowest full saturation osmotic potential, after drought. These plants also maintained higher turgor across a range of leaf water potentials and relative water contents. Leaf water content at full turgor and relative water content at the turgor loss point were also lower in plants without N. N treatments of 200 and 500 ppm had similar water relations under both well-watered and drought conditions.
Spectral Transmittance of Selected Greenhouse Construction and Nursery Shading Material
Authors: McMahon M.J. , Kelly J.W. , Decoteau D.R.
Published: August 2020

Spectral transmittance properties of several greenhouse construction and shading materials were determined by measuring the quantity and quality of solar radiation transmission on non-clouded (sunny) days at solar noon. Spectral transmittance parameters included photosynthetic radiation (400–700 nm) and photomorphogenic radiation (660 nm (red light), 730 nm (far-red light), and 400–500 nm (blue light). Light available for photosynthesis was measured as photosynthetic photon flux density (PPFD) and photosynthetic radiation (PI). Photomorphogenic radiation was measured as far-red/red (FR/R) and blue light. Greenhouse construction materials included glass, chambered acrylic, chambered polycarbonate, and inflated plastic film. Various shade materials of different colors were evaluated. Photosynthetically active radiation transmission of construction materials ranged from approximately 95% transmission of direct sunlight with Exolite to less than 50% with tinted Lexan. Far-red/red values of shade materials ranged from 0.94 for Enduro Green to 5.58 for Cravo LS-7.
A Survey of Weed Control Costs and Strategies in Container Production Nurseries
Authors: Gilliam Charles H. , Foster William J. , Adrain John L. , Shumack Ronald L.
Published: August 2020

Thirty-two container nurseries were surveyed concerning weed management strategies. Handweeding costs ranged from $608–$1401/ha ($246–$567/acre), with hourly wages paid for handweeding ranging from $3.53 to $3.97/hour. Nurseries averaged 3 applications of preemergence applied herbicides annually. Primary herbicides applied were OH-2 (oxytluorfen + pendimethalin), Rout (oxytluorfen + oryzalin) and Ronstar (oxadiazon). Problem weeds identified by the participants were prostrate spurge (Euphorbia supina Raf.), oxalis (Oxalis sp.), eclipta (Eclipta alba (L.) Hasskarl) and nutsedge [Cyperus esculentus L. (yellow) and C. rotundus L. (purple)]. Weed control material used under containers varied with the nursery size.
Response of Different Syringa (Lilac) Species and Hybrids to Renovation
Authors: Davidson Campbell G. , Remphrey William R.
Published: August 2020

Eighteen species and hybrids of Syringa were renovated by removing all stems. At the end of 4 years, shoot growth, shoot diameter, and numbers of lateral shoots produced were evaluated to assess species differences in growth response. In most species, there was an initial rapid growth rate followed by a decline. The decline in growth rate may be related to increasing architectural complexity as the shoot system develops. Genotypic differences in stem diameter, height growth progression and the number of lateral shoots have a principal role in plant form development and should be considered when selecting plants with particular textural characteristics for landscape plantings. In addition, these response patterns may be a useful guide for predicting growth and development after renovation of a particular species and hybrids.
Micropropagation and Field Evaluation of × Heucherella ‘Bridget Bloom’
Authors: Kitto S.L. , Frett J.J. , Geiselhart P.
Published: August 2020

× Heucherella ‘Bridget Bloom’ shoots were surface disinfected and cultured on basal medium composed of Murashige-Skoog salts and vitamins and the following addenda per liter; sucrose, 30 g; glycine, 2 mg; and washed Difco Bacto-agar, 6 g. Axillary shoot proliferation was greatest on medium supplemented with 0.5 mg 1−1 benzyladenine, 0.025 mg 1−1 naphthaleneacetic acid and 4 g 1−1 washed Difco Bacto-agar. Adventitious shoots regenerated from callus that initiated from the base of cultured microcuttings. Microcuttings were rooted in Redi-Earth under intermittent mist for 4 wk (94% rooted) and then moved to a greenhouse (98% survival after 4 wk). During a 16 month field study, plants produced from microcuttings grew as well as, if not better than, greenhouse-grown plants propagated by division. Micropropagated plants originating from axillary buds had significantly greater fresh and dry weights, and initiated more leaves and crowns when grown under field conditions than plants originating from adventitious buds.
Overwintering Container-grown Nursery Crops: Plant, Air and Medium Thermal Response to Porous Row Covers
Authors: Warren Stuart L. , Perry Katharine B. , Bir Richard E.
Published: August 2020

Three structureless row covers (white, spunbonded polyester and two weights of white, spunbonded polypropylene) were evaluated for winter protection of container grown ‘Helleri’ holly (Ilex crenata ‘Helleri’), ‘Atropurpurea Nana’ nandina (Nandina domestica ‘Atropurpurea Nana’), Fraser photinia (Photinia × fraseri), and ‘Mohave’ pyracantha (Pyracantha Koidzumii × coccinea ‘Mohave’) relative to white copolymer film and white copolymer backed thermoblanket over quonset-shaped structures and an unprotected control. Air and rooting medium temperatures were monitored during the deployment period. Visual foliar injury ratings were taken immediately after treatments were removed and again four months later. Visual shoot injury ratings were correlated with the mean daily average and the mean daily minimum temperature of air and rooting medium within each treatment. Both polypropylene covers provided protection for plants in the interior of a consolidated group equivalent to white poly and the thermoblanket for all species except Pyracantha. Porous row covers are a feasible alternative to standard protection systems.
Response of Two Forcing Azalea Cultivars to Bonzi and B-nine Applications
Authors: Keever Gary J.
Published: August 2020

Bonzi (paclobutrazol) sprays of 50, 100, and 150 ppm applied either 1 day before or 1 day after cooling reduced bypass shoot number and length of Dorothy Gish White and Roadrunner azaleas (Rhododendron × ‘Dorothy Gish White’ and R. × ‘Roadrunner’) compared to the control. Flowering was delayed 3 to 8 days depending upon cultivar, rate, and time of application, while bloom diameter was reduced slightly (Dorothy Gish White) or not affected (Roadrunner) by paclobutrazol. B-nine (daminozide) had little effect on either bypass shoot development or flowering of Roadrunner, but reduced flower diameter and· delayed flowering of Dorothy Gish White azalea relative to the control.
Growth Analysis of ‘Plumosa Compacta’ Juniper and ‘Coral Beauty’ Cotoneaster Subjected to Different Nitrogen Fertilizer Regimes
Authors: Hicklenton Peter R.
Published: August 2020

‘Plumosa Compacta’ juniper (Juniperus horizontalis Moench.) and ‘Coral Beauty’ cotoneaster (Cotoneaster dammeri C. K. Schneid.) were container grown in a bark:peat-sand medium (2:1:1 by vol.). Plants received either 70, 140, 280 or 420 mg (0.003, 0.005, 0.010 or 0.015 oz) N per week from nutrient solutions. Growth was assessed on plants harvested from each treatment regime on May 22 and then at monthly intervals until September 16. Juniper plants grown with 140 mg (0.005 oz) N per week were larger at the end of the season than those in the other treatments. In cotoneaster, growth increased as weekly N application increased from 70 to 420 mg (0.03 to 0.015 oz) N per week. Path analysis was used to quantify the effect of plant relative growth rate (RGR) during each month on RGR in subsequent months and on total seasonal relative dry weight gain (TRWG). RGR during each month significantly influenced TRWG, with the periods from June 21 to July 20, and from July 21 to August 18 exerting the greatest influence in cotoneaster. In juniper, the influence of RGR in each month on TRWG was equal. For both cotoneaster and juniper, increasing RGR during one month tended to have a negative influence on RGR during subsequent months.
Improvement of Seedling Emergence of Lupinus texensis Hook. Following Seed Scarification Treatments
Authors: Davis Tim D. , George Steven W. , Upadhyaya Abha , Persons Jerry
Published: August 2020

Seeds from four commercial seedlots of Lupinus texensis Hook. (Texas bluebonnet) were placed in concentrated sulfuric acid for 0 to 120 minutes and then sown. Emergence was promoted by acid scarification in three of the four seedlots. For the lots that responded to acid scarification, the optimal scarification time was 30–60 minutes which resulted in 85–95% emergence one month after planting. In addition to increasing the total number of seedlings that emerged, acid scarification hastened emergence. The same aliquot of sulfuric acid was used for five 60-minute scarification periods before its efficacy was reduced. Acid scarification did not reduce seed coat thickness or strength but created several small pores in the seed coat which likely facilitated imbibition. Cutting, filing, or piercing the seed coat promoted emergence to a similar extent. Placement of seeds in 85%C (185%F) water and then cooling for 24 hrs promoted emergence relative to the non-treated controls, but was not as effective as other scarification techniques. Freezing and thawing of seeds had no effect on emergence. Results indicate that acid scarification functions by removing a mechanical rather than a chemical barrier to gennination of L. texensis.
Effects of Container Medium Peat Content and Bed Surface on Plant Growth During Capillary Irrigation
Authors: Banko Thomas J. , Stefani Marcia A.
Published: August 2020

Rhododendron indicum ‘Formosa’ (Formosa azalea), Buxus sempervirens (Common boxwood), and B. microphylla koreana (Korean boxwood) were grown on capillary irrigation beds of fine mortar sand kept moist with water distributed through drip tubing. The proportion of peat in the pine bark:peat:sand container medium had a significant effect on plant growth, with growth generally increasing as peat content increased from 0 to 40%. Covering the sand beds with Visqueen ground cover film to control weeds and to prevent root growth from the pots into the sand reduced plant growth, apparently by interfering with capillary flow of water from the sand to the container medium. Spraying the sand surface with Surflan A.S. (oryzalin) at 3.36 kg/ha (3 lbs ai/A) reduced weed establishment early in the growing season, but had little effect on weeds or growth of Korean boxwood roots into the sand 4 months after study initiation.
Cold Storage of Rooted Taxus Cuttings on Subsequent Summer Regrowth
Authors: McGuire John J. , Johnson Wm. A. , Dawson Charles
Published: August 2020

After one growing season, root systems of Taxus media ‘Nigra’ and ‘Densiformis’ were similar, whether or not these fall-propagated rooted liners were given a cold treatment [−2.2°C (28°F) for 8 weeks] or left in the propagating beds until spring. However, storage did make propagation space available for two months for other uses. Outdoor spring propagated cuttings had more roots and a greater root shoot/ratio than indoor fall rooted cuttings, whether the latter were cold-treated or not.
Seed Germination of Rhododendron catawbiense and Rhododendron maximum: Influence of Light and Temperature
Authors: Blazich Frank A. , Warren Stuart L. , Acedo Juan R. , Reece William M.
Published: August 2020

Seeds of Rhododendron catawbiense Michx. and Rhododendron maximum L. were germinated at 25°C (77°F) and 25°/15°C (77°/59°F) with daily photoperiods of 0, 1/2, 1/2 twice daily, 1, 2, 4, 8, 12, or 24 hr. After 30 days at 25°C (77°F), germination of R. catawbiense in darkness was 5% but increased to 64% at 25°/15°C (77°/59°F). At both temperatures, gernlination >95% was attained by day 15 for photoperiods of 1/2 to 12 hr. Regardless of temperature, seeds of R. maximum required light for germination. At 25°C (77°F), increasing photoperiods increased germination with 79 and 81% germination occurring by day 21 for the 12- and 24-hr photoperiods, respectively. The alternating temperature of 25°/15°C (77°/59°F) enhanced germination when light was limiting. At this temperature, germination of 92 to 97% was reached by day 21 for photoperiods ≥4 hr.
Propagation of Firebush (Hamelia patens) by Stem Cuttings
Authors: Davis Tim D. , George Steven W. , Upadhyaya Abha , Parsons Jerry
Published: August 2020

The influence of bottom heat, rooting medium, type of cutting (i.e. terminal vs. subterminal), and commercial auxin formulations on greenhouse propagation of firebush (Hamelia patens Jacq.) by leafy stem cuttings during winter was investigated. Without bottom heat, mid-day rooting medium temperature averaged about 22 ± 3°C (72 ± 5°F). Percent rooting of auxin-treated cuttings without bottom heat was 50% and mean length of the longest root and visual rating scores of root development were low. Maintaining the rooting medium at 29–39°C (85–10 1°F) increased percent rooting for auxin-treated cuttings to 96–100% and increased root length and visual rating scores several-fold. Rooting percentage, root length, and visual rating scores were consistently high in perlite and low in peat moss. Terminal stem-tip cuttings and subterminal stem segment cuttings with basal stem diameters of 3–5 mm (0.13–0.20 in) rooted slightly better than subterminal stem segment cuttings which had basal stem diameters of 6–8 mm (0.25–0.32 in.). Terminal stem-tip cuttings not treated with auxin but with bottom heat had rooting percentages of 81–86%. Treatment of terminal stem-tip cuttings with Rootone F or Wood's Rooting Compound (1:20 or 1:5 dilution) generally resulted in rooting percentages above 90%. Some of the auxin treatments also resulted in increased root length and visual rating scores. Despite these differences, none of the plants grown from auxin-treated cuttings, were distinguishable from plants grown from nontreated cuttings two months after the rooting period. Of the variables studied, bottom heat had the most dramatic effect on rooting of stem cuttings during winter months.
Effect of Seasons and Irrigation Regimes on Plant Growth and Water-Use of Container-Grown Photinia × fraseri
Authors: Welsh Douglas F. , Zajicek Jayne M. , Lyons Calvin G.
Published: August 2020

Water-use and plant growth of Fraser photinia (Photinia × fraseri Dress) were studied under varying irrigation regimes during 2 different growing seasons, winter and summer. Rooted cuttings were transplanted into 7.57 1 (2 gal) plastic containers containing Metro-mix 500 and greenhouse-grown under 2 irrigation frequencies (3.5 or 7-day intervals) and 3 replacement amounts (100%, 75% or 50% replacement of actual water-use).

Increased irrigation frequency significantly reduced plant growth parameters of winter-grown plants, including shoot growth, leaf number, leaf area and shot dry weight. Decreased irrigation amount significantly increased root dry weight. Significant differences were not detected in growth measurements of summer-grown plants suggesting differences between experiments are seasonal in nature. Frequent irrigation resulted in poor plant pelformance under winter growing conditions of lower evapotranspiration (ET); however under summer growing conditions, frequent irrigation did not significantly affect plant growth.

Decreased irrigation frequency significantly increased total water-use for winter-grown plants due to increased plant performance. No significant differences in water-use due to frequency in summer-grown plants was found.
Time of Transplanting Liners and Initial Growing Location Affects Growth of Woody Nursery Plants
Authors: Laiche Adolph J.
Published: August 2020

Liners of four cultivars were planted in larger containers and subjected to selected production systems. Objectives were to compare planting liners in September or December and growing these plants can-to-can out-of-doors or in a polyhouse vs planting in April or May of the following year.

Substantially more shoot fresh weight was obtained with three of the four test species by planting liners in larger containers in September before cold weather occurred compared to planting in December, April or May of the following year. In general, planting liners in December compared to planting in April of the following year did not result in an increase in shoot fresh weight. Late planting in May, rather than in April, resulted in less shoot fresh weight and lower root ratings with three of the four species tested. Growing plants in a polyhouse compared to out of doors resulted in more shoot fresh weight only with Ilex crenata ‘Compacta’ and Rhododendron ‘Formosa’ planted in September and with Ilex cornuta ‘Anicet Delcambre’ planted in December.
Kairomone Response, Pesticide Tolerance and Field Efficacy of the Predatory Mite, Neosieulus collegae (De Leon)
Authors: Mizell Russell F. , Schiffhauer Daniel E.
Published: August 2020

Neosieulus (Cydnodromus) collegae (De Leon) (Acari:Phytoseiidae) is a heretofore relatively unknown species of predatory mite. In an olfactometer, female predators were attracted to kairomones produced by Tetranychus urticae Koch, Oligonychus ilicis (McGregor), O. ununguis (Jacobi), Eotetranychus hicoriae (McGregor), and E. sexmaculatus (Riley). Predators were repelled by odors emanating from lima bean leaves treated with Mavrik (fluvalinate) and Ammo (cypermethrin), but unresponsive to those treated with Tame (fenpropathrin) and Talstar (bifenthrin). This predator species was tolerant of residues of Vendex (hexakis), Omite (propargite), Pentac (dienochlor) and Avid (abamectin) but not to residues of Tame (fenpropathrin) and Kelthane (dicofol). Eggs of T. urticae treated with Tame (fenpropathrin) were toxic to the predator when consumed. Female N. collegae would not consume eggs treated with Avid (abamectin); starvation reduced fecundity. Prey eggs treated with Vendex (hexakis) and Omite CR (propargite) were consumed without affecting predator fecundity or mortality. Eggs treated with Pentac (dienochlor) or Kethane (dicofol) were consumed, but significantly reduced predator fecundity. Predators released into plots in a commercial nursery during winter in north Florida reduced field populations of T. urticae within 20–30 days, if released in high numbers. Neosieulus collegae may have significant potential as a biological control agent in nursery crops for control of mite pests.
Market Demands and Characteristic Preferences for Pine Straw in Alabama
Authors: Dyer Janice F. , Barlow Rebecca , Keever Gary J. , Morse Wayde
Published: August 2020

Pine straw is a popular landscape mulch material used by landowners and homeowners throughout the southeastern United States. Pine straw is collected, transported, and sold through an informal network of landowners, harvesters, forest labor contractors, and dealers. Quality varies widely, depending on factors such as species of pines, land management practices, and harvesting techniques. A mail survey of landscapers, retailers, and lawn maintenance specialists was used to assess market demand and characteristic preferences of those buying and selling pine straw in Alabama. Purchase volumes varied widely among buyers, both annually and for single-time purchases. Buyers placed high importance on straw free from weeds and foreign material. There were differences in species of pine straw purchased among respondents, some of which appear attributable to location of the buyer. While there was a strong preference for longleaf pine straw, those who reported purchasing loblolly and slash were more likely to prefer those species. Responses from buyers who know their pine straw's origin reveal differences in the distance from which they purchase pine straw, with many buying straw from more than 150 miles away. Results also show that many do not know where their pine straw comes from or what species it is.
Landscape Establishment of Woody Ornamentals Grown in Alternative Wood-Based Container Substrates
Authors: Marble S. Christopher , Fain Glenn B. , Gilliam Charles H. , Runion G. Brett , Prior Stephen A. , Torbert H. Allen , Wells Daniel E.
Published: August 2020

Due to concerns over future pine bark (PB) availability for container plant production, recent research has focused on evaluating suitable alternatives. For alternatives to be considered suitable substrate replacements, they must not only have desirable characteristics as a container substrate (e.g., adequate drainage, inert, pathogen free, etc.), but must also cause no negative fertility effects (e.g., nitrogen immobilization) following planting in the landscape. The study objective was to evaluate the landscape performance of three woody ornamentals grown in PB and in two alternative wood-based substrates, namely WholeTree (WT) and Clean Chip Residual (CCR). Crapemyrtle (Lagerstroemia indica × faurei ‘Acoma’), magnolia (Magnolia grandiflora ‘D.D. Blanchard’), and shumard oak (Quercus shumardii) were container grown in PB, WT, or CCR for an entire growing season prior to being planted into the landscape. Plants were grown in the landscape for two growing seasons. Data suggest that all species exhibited similar landscape performance when grown in WT or CCR compared to the PB standard. Therefore, the use of WT and CCR as alternative wood-based substrates for crapemyrtle, magnolia, and oak production may be acceptable from a landscape establishment standpoint.
Shoot Wilt of Petunia sp. Following Drenching with Exogenous ABA
Authors: Beeson R.C.
Published: August 2020

A new agricultural product containing the physiologically active cis form of abscisic acid (C-ABA) is scheduled to become available for ornamental production in 2012. This plant growth regulator generally prolongs irrigation intervals of ornamental plants. During pre-registration testing, the product greatly reduced whole plant transpiration on a variety of species, extending the time between irrigations whether applied as a drench or a foliar spray. However in some instances, drench application resulted in whole plant wilting of some annual species after one to three days. This occurred most often with certain cultivars of coleus, tomato and petunia. Investigations reported here associate wilting of petunia with low xylem water potential and near complete stomatal closure caused by prevention of water movement into root stele. Evidence is presented implicating that the exogenous C-ABA induced closure of root aquaporins led to shoot wilt.
Influences of Shading and Fall Fertilization on Fluorescence, Freeze Resistance, Flower Production and Growth of Rhododendron ×kurume ‘Pink Pearl’
Authors: Henning Frank P. , Smalley Timothy J. , Lindstrom Orville M. , Ruter John M.
Published: August 2020

We investigated the influences of fall fertilization and light intensity on photosynthesis and freeze resistance of Rhododendron ×kurume ‘Pink Pearl’, an evergreen azalea cultivar, grown outdoors in containers under nursery conditions. The study included two main-plot fall fertilization treatments: 1) 0.5 liter solution containing 75 mg·liter−1 N applied for 60 days from August 1 through September 29 and 2) 0.5 liter solution containing 125 mg·liter−1 N applied for 120 days from August 1 through November 28, and four subplot light intensity treatments 1) 100% ambient photon flux density (PPFD) from May 1, 2004, through May 1, 2005, 2) shade fabric rated to reduce PPFD by 50% from May 1 through September 30, 2004, followed by 100% PPFD from October 1, 2004, through May 1, 2005, 3) 100% PPFD from May 1 through September 30, 2004, followed by 50% PPFD from October 1, 2004, through May 1, 2005, and 4) 50% PPFD from May 1, 2004, through May 1, 2005. Fertilizer application and shade treatments did not interact in their effects on stem freeze resistance or the timing of anthesis. The high rate of extended fertigation (125 mg·liter−1 N applied August 1 through September 28) reduced freeze resistance of azalea stems and advanced anthesis by 4.9 days compared to plants that received moderate fertigation (75 mg·liter−1 N from August 1 through September 29). The high rate of extended fall fertigation failed to increase leaf or stem dry weight compared to plants that received the moderate rate of fertigation. Plants grown in 50% PPFD from May 1 through September 30 produced 163% more above ground dry weight compared to plants grown in 100% light during the same time period. The addition or removal of shade cloth beginning October 1 failed to enhance azalea stem freeze resistance compared to plants that were only exposed to 100 or 50% PPFD respectively. Shade treatments affected the chlorophyll fluorescence ratio (Fv · Fm−1) of leaves, but leaf fluorescence was unrelated to stem freeze resistance. Shade treatments affected azalea growth and photosynthetic stress, but shade neither interacted with fall fertilization to increase stem freeze resistance, nor had a biologically significant effect on stem freeze resistance.
Propagation of Ilex vomitoria ‘Dare County’ by Stem Cuttings
Authors: Lambert Christopher R. , Blazich Frank A. , LeBude Anthony V.
Published: August 2020

Semi-hardwood or hardwood stem cuttings of Ilex vomitoria Sol. ex Ait. ‘Dare County’ [‘Dare County’ yaupon holly (syn. ‘Virginia Dare’ yaupon holly)] were treated with solutions of the potassium (K) salt (K-salt) of indolebutyric acid (K-IBA) at 0 to 8000 mg liter−1 (ppm). Nontreated semi-hardwood cuttings rooted at 78% whereas, regardless of auxin treatment, hardwood cuttings taken on two dates rooted at 15%. Treatment of cuttings with K-IBA was generally ineffective and resulted in a linear decrease (P ≤ 0.05) in percent rooting of semi-hardwood cuttings.
Impact of Bispyribac-sodium Application on Annual Bluegrass Control and Brown Patch Severity in Tall Fescue
Authors: Cutulle Matthew , Derr Jeffrey , Nichols Adam , McCall David , Horvath Brandon
Published: August 2020

Annual bluegrass (Poa annua L.) is a problematic weed in tall fescue [Festuca arundinacea (Schreb.) S.J. Darbyshire], with limited options available for postemergence control. Field research was conducted to evaluate bispyribac-sodium application rates (37 or 74 g ai·ha−1) (0.033 or 0.066 lb ai·A−1) and timings (March, April or May) as well as iron supplementation on brown patch (Rhizoctonia solani) severity, annual bluegrass control, and tall fescue quality. In general, applying bispyribac-sodium to tall fescue did not result in significantly more brown patch than in untreated plots in field trials. Applying bispyribac-sodium in March or April resulted in significantly higher annual bluegrass control than applications in May. In greenhouse experiments, bispyribac-sodium at 37 and 74 g ai·ha−1 (0.033 or 0.066 lb ai·A−1) was applied to brown patch-inoculated tall fescue plants. Under conditions of high inoculum and humidity in those greenhouse studies, applications of bispyribac-sodium increased the number of brown patch lesions relative to untreated plants. Tall fescue plant height was initially reduced after being treated with bispyribac-sodium; however, six weeks after application tall fescue plants in treated with herbicide were taller than the nontreated plants.
Management of Pests, Plant Diseases and Abiotic Disorders of Magnolia Species in the Southeastern United States: A Review
Authors: Knox Gary W. , Klingeman William E. , Paret Mathews , Fulcher Amy
Published: August 2020

The genus, Magnolia, encompasses a group of about 240 species of evergreen or deciduous trees and large shrubs. Magnolias are native to temperate, subtropical and tropical areas of southeastern Asia, eastern North America, Central America, the Caribbean and parts of South America. Native and nonnative Magnolia species have become prominent landscape plants in the southeastern U.S. due to their beauty, utility, relative ease of maintenance and broad adaptability to the region's climate and soils. Species introductions, breeding and selection programs over the last 50 years have produced superior selections with improved flowering, new flower colors and ornamental foliage and buds often featuring brown, copper or gold indumentum. Magnolia health and pest management is sometimes overlooked in both landscape and production settings because magnolia is considered to have relatively few pest and disease problems. Some abiotic disorders may mimic biotic damage or may render magnolia more susceptible to pests and diseases. When they occur, abiotic disorders, pests or diseases on magnolia can cause significant economic or aesthetic losses. This review focuses on magnolia culture in production and landscape settings with an emphasis on major pests, plant diseases and abiotic disorders affecting management of Magnolia species.