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  • Author or Editor: Charles H. Gilliam x
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The objective of this study was to evaluate the potential use of container substrates composed of whole pine trees. Three species [loblolly pine (Pinus taeda), slash pine (Pinus elliottii) and longleaf pine (Pinus palustris)] of 8–10 year old pine trees were harvested at ground level and the entire tree was chipped with a tree chipper. The chips from each tree species were then further processed with a hammer mill to pass a ½-inch screen. On 29 June 2005 these three substrates along with 100% pinebark were mixed with the addition per cubic yard of 9.49 kg·m–3 Polyon 18–6–12 (18N–2.6P–10K), 2.97 kg·m–3 dolomitic lime and 0.89 kg·m–3 Micromax. One gallon (3.8 L) containers were then filled and placed into full sun under overhead irrigation. Into these containers were planted 72 cell plugs of Catharanthus roseus`Little Blanche'. Data collected were pre-plant chemical and physical properties of substrates, as well as plant growth index (GI), plant top dry weight, root ratings, and plant tissue (leaves) nutrient analysis at 60 days after planting (DAP). The test was repeated on 27 Aug. 2005 with C. roseus Raspberry Red Cooler. Top dry weights were on average 15% greater for the 100% pinebark substrate over all others at 60 DAP. However there were non differences in plant GI for any substrate at 60 DAP. There were no differences in plant tissue macro nutrient content for any substrate. Tissue micronutrient content was similar and within ranges reported by Mills and Jones (1996, Plant Analysis Handbook II) with the exception of Manganese. Manganese was highest for slash and loblolly pine and well over reported ranges. There were no differences in root ratings. There were no differences in substrate physical properties between the three whole tree substrates. However the 100% pinebark substrate had on average 50% less air space and 25% greater water holding capacity than the other substrates. Physical properties of all substrates were within recommended ranges. Based on the results of this study substrates composed of whole pine trees have potential as an alternative sustainable source for a substrate used in producing short term nursery crops.

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Lagerstroemia × `Natchez' and Quercus virginiana were planted into a sandy loam soil in grow bags and by traditional field planting methods. After 2 years in the field, 1 sample from each of 6 replications was dug from the field in March. Root and top growth were measured. Half the remaining plants were dug and transplanted into 76 liter containers for 3 months. Growth indices were measured at this time. The remaining trees in the field were dug in July and handled similarly. Data from live oak trees showed increased height in trees produced by traditional field planting methods. No differences between planting methods were found in any other growth indices for the two species. Both crapemyrtle and live oak trees transplanted from traditional field plantings in March had greater height than trees transplanted from grow bags. However, no differences were detected for top weight, caliper or root ratings. July transplanted crapemyrtles showed no differences in any of the growth indices. Live oaks transplanted in July from traditional field plantings to containers all died with no additional growth. Grow bag transplanted oaks survived and continued to grow.

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Hardy ferns are widely grown for use in the landscape. Studies were conducted to evaluate the tolerance of variegated leatherleaf fern (Arachniodes simplicor `Variegata'), tassel fern (Polystichum polyblepharum), autumn fern (Dryopteris erythrosora), holly fern (Cyrtomium falcatum `Rochfordii'), and southern shield fern (Dryopteris ludoviciana), to applications of selected preemergence applied herbicides. Liquid applied herbicides were pendamethalin (LPM) at 3.36 or 6.73 kg·ha–1, prodiamine (LPD) at 1.12 or 2.24 kg·ha–1, isoxaben (LIB) at 1.12 or 2.24 kg·ha–1, and the combination of prodiamine plus isoxaben (LPI) at 1.12 plus 1.12 kg·ha–1. Granular applied herbicides were pendamethalin (GPM) at 3.36 or 6.73 kg·ha–1, prodiamine (GPD)1.12 or 2.24 kg·ha–1, oxadiazon plus prodiamine (GOP) at 1.12 + 0.22 or 2.24 + 0.44 kg·ha–1, oxyfuorfen plus oryzalin (GOO) at 2.24 + 1.12 or 4.48 + 2.24 kg·ha–1, trifluralin plus isoxaben (GTI) at 2.24 + 0.56 or 4.48 + 1.12 kg·ha–1, oxadiazon (GO) at 4.48 or 8.97 kg·ha–1, and oxadiazon plus pendamethalin (GOPD) at 2.24 + 1.4 or 4.48 + 2.8 kg·ha–1. The greatest reduction in growth of autumn fern was observed with GOPD, GO, and GOP; all three containing oxadiazon as an active ingredient. Reductions in holly fern growth were most severe when plants were treated with GTI resulting in a 42% and 54% decrease in frond length and frond number, respectively. There were also reductions in number of fronds when treated with LPM, GPM, GOP, GOO, and GOPD. There were no reductions in frond numbers on tassel fern with any herbicides tested. However, there were reductions in frond length from 6 of the 10 herbicides evaluated. The most sensitive fern to herbicides evaluated in 2004 was leatherleaf with reductions in frond length and number of fronds with 6 of the 10 herbicides tested. While all herbicides tested on southern shield fern appeared to be safe, especially in the 2004 study, tassel fern and holly fern appear to be more sensitive. GPD proved to be a safe herbicide for all species tested in both 2004 and 2005. In 2005 all plants from all treatments were considered marketable by the end of the study. However there was significant visual injury observed on the holly fern treated with LIB at 60 and 90 days after treatment which might reduce their early marketability.

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Abstract

Photinia Χ fraseri Dress (Fraser Photinia) plants were dug and burlapped in the morning and afternoon during midsummer with or without previous irrigation or antitranspirant treatment (di-1-p methene = Vapor Gard). Plants were shipped for one day, held for 2 weeks under lath, and then planted. Moisture stress, indicated by shoot water potential, was monitored throughout the study and survival was rated in September. Use of the antitranspirant and morning digging reduced moisture stress of plants. Morning-dug plants had 80% or greater survival even without irrigation. Afternoon digging gave low survival with or without irrigation but afternoon digging plus Vapor Gard gave 100% survival.

Open Access

Abstract

Postemergence applications of 1.1 and 0.6 kg/ha of sethoxydim (2-[l-ethoxyimino) butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-l-one) and fluazifop-butyl (butyl 2-[4-(5-trifluoromethyl-2-pyridyloxy)-phenoxy]propionate), respectively, resulted in 90% control of common bermudagrass (Cynodon dactylon) when applied directly over field-grown ornamentals. Comparable control was achieved by either single application or 2, half-rate, split applications. Of the 12 species tested, only ‘Hexe’ azalea was damaged by applications of fluazifop-butyl to a degree that the plants were unsaleable. All other species exhibited tolerance to both sethoxydim and fluazifop-butyl at the rates required to achieve grass control.

Open Access

Abstract

Gardenia jasminoides Ellis and Ilex crenata Thunb. ‘Compacta’ were field-grown with 4 irrigation rates based on 0%, 25%, 50%, and 100% replacement of net evaporation from a class A pan. Irrigated gardenia were larger than nonirrigated gardenia, and those grown with 50% and 100% replacement of net evaporation had greater total root growth than nonirrigated plants. Root number, root dry weight, and fibrous root number in a 20-cm rootball were generally greater with irrigated plants than nonirrigated plants. Ilex crenata shoot growth was greater also with irrigation versus nonirrigation. Based on this data, 25% replacement of net evaporation resulted in plants of both species being similar to higher irrigation rates.

Open Access

Abstract

Boston fern [Nephrolepsis exaltata (L.) Schott ‘Compacta’] was grown with 3 rates of 2 slow-release fertilizers and with one rate of liquid fertilization. Greatest fern dry weight occurred with ferns grown with liquid fertilization (20N–0.8P–16.6K) or Osmocote (19N–2.5P–8.3K) at the 1.8 kg N/m3 rate. After 16 weeks of simulated commercial production, one-third of the ferns were moved to a low-light interior environment, while one-third were held in the greenhouse. Six weeks later, ferns moved to the interior environment were greener in color, had greater nutrient content, and exhibited less growth than did ferns held in the greenhouse.

Open Access

Abstract

In field production of nursery stock, plant losses may occur after digging but before plants leave the nursery, thereby reducing profitability. Although little information is available, it appears this plant loss may result from moisture stress induced by root pruning at digging and subsequent handling procedures (2, 3). To ensure adequate roots in the rootball, most nurserymen dig root-balls in accordance with the American Standard for Nursery Stock (ASNS) (1), which allows for increasing rootball size with increased shoot growth.

Open Access

Abstract

Postemergence and preemergence control of goosegrass [Eleusine indica (L.) Gaertn.] and large crabgrass [Digitaria sanguinalis (L.) Scop.] were evaluated with clopropoxydim, fenoxaprop-ethyl, xylofop-ethyl, and poppenate-methyl. None of these herbicides was injurious to Rhododendron obtusum ‘Coral Bells’, Ilex crenata ‘Compacta’, Euonymus alatus ‘Compacta’, Juniperus horizontalis ‘Plumosa’, or Thuja occidentalis ‘Pyramidal’ and, depending on rate, provided acceptable grass control. Only xylofop-ethyl at 0.12 kg ha−1 and poppenate-methyl at 1.12 kg·ha−1 consistently provided at least 90% control. Poppenate-methyl also provided preemergence activity for one to six weeks. Chemical names used: (E,E)-2-[l-[[(3-chloro-2-propeny)oxy]imino]butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-eyclohexen-l-one (clopropoxydim); (±)-ethyl 2-[4-[(6-ehloro-2-benzoxazolyl)oxy]phenoxy]propanoate (fenoxapropethyl); 2-[4-[(6-chloro-2-quinoxalinyl)oxy]-phenoxy]propionic acid (xylofop-ethyl); and methyl-3-hydroxy-4[4-[[5-(trifluoromethyl)-2-pyridinyl]oxy]phenoxy]-pentanoate (poppenate-methyl).

Open Access