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Abstract
Wire baskets are an integral part of transplanting landscape trees and are designed for many types and sizes of mechanical tree spades. The wire basket functions as support for the root ball and as a means of lifting the tree (3). Most baskets are made from galvanized wire and are left intact at planting (P. Braun, personal communication), although some specifications require their removal (1). The potential longevity of the wire in the soil has led to concern and speculation about adverse effects of the basket on tree growth (4). Root girdling, tree instability, reduced shoot growth, and premature decline have been suggested as possible effects on trees planted in intact wire baskets (2, 5).
Abstract
Preventing fruit formation may be desirable for several reasons: they may retard tree growth and development, present unpleasant odors, make mowing and maintenance difficult, clog drains, attract undesirable birds and insects, stain cars and patios, or be aesthetically unattractive.
Abstract
Shoot dry weight of container-grown Thuja occidentalis L. ‘Pyramidalis’, pyramid white cedar and Forsythia intermedia Zab. ‘Spectabilis’, showy border forsythia, was less in mixes containing municipal waste compost than in a moss peat:sand mix. Severe marginal leaf necrosis of Forsythia and browning of older shoot tips of Thuja occurred on plants in compost mixes. Accumulation of foliar B was 32 times greater in Forsythia and 4 times greater in Thuja grown in 1 compost: 1 sand than in 1 moss peat:l sand. Leaching reduced high salts but did not reduce B toxicity. Compost mixes subsided much more than the moss peat mix.
Abstract
Preplant chilling of rooted cuttings and postplant night lighting influenced the growth of ‘Hicks’ yew (Taxus × media Rehd. ‘Hicksii’). Supplemental light from high-pressure sodium (HPS) lamps, provided during the first year, enhanced shoot length and number in the first year, but not in the second. Compared to natural light, HPS increased shoot length 3 to 5 times and shoot number 3 and 4 times in the first year. The influence of incandescent light on growth was less, being significant on unchilled but not chilled plants, and not beneficial when continued for 2 years. In the second year, plants under natural light grew as much or more than plants under either HPS or incandescent light. The trend of increased shoot length in the first year by chilled plants under natural light was not evident for lighted plants, nor was there any benefit of chilling on shoot number. A trend for less growth in the second year by chilled plants was evident. The delay in initiation and development of buds on accelerated plants had an adverse effect on growth the second year.
To minimize fertilizer and water use, and NO3-N runoff from container culture, growth, and nutrient status of forsythia (Forsythia ×intermedia Zab. ‘Spring Glory’) in No. 2 containers were compared in response to a controlled-release fertilizer (CRF; Nutricote 18-6-8 100-day at rates of 2, 4, and 6 kg·m−3) and placements (incorporation and topdress) under three irrigation strategies [drip-irrigated low (25% or less) leaching fraction (DrLoLF), hand-sprinkled low leaching fraction (HsLoLF), and hand-sprinkled high (50% or less) leaching fraction (HsHiLF)]. In a coexperiment under drip irrigation only, forsythia response was also examined under incorporation, topdress, and dibble fertilizer placements with the same CRF rates applied as single or split dose. Dibble fertilizer placement was superior to both incorporation and topdress in this order. Maximum growth of forsythia occurred at rates of 4.7 kg·m−3 with dibble. With incorporation and topdress, maximum growth was not achieved even at the 6 kg·m−3 maximum rate tested. Forsythia grew better with incorporated than with topdressed CRF with the DrLoLF treatment. The response was reverse with HsHiLF or showed no differences with HsLoLF. Under drip irrigation, greater concentrations of NO3-N generally leached from incorporation and dibbled containers in this order than from topdress. Less nitrate was leached from the topdressed containers because less was released from the CRF prills. At the 6 kg·m−3 CRF rate, total cumulative NO3-N leachings were 76, 85, and 22 kg·ha−1 (45 × 45-cm container spacing) for dibbling, incorporation, and topdress, respectively, under drip irrigation. Split application of CRF greatly reduced NO3-N in leachate, although plant growth also was reduced as a result of less availability of and uptake of nutrients under this strategy.