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Norway spruce (Picea abies (L.) Karst.) is shade-tolerant and sensitive to high irradiance, summer frosts and winter desiccation, which can impair its reforestation success. In this study, artificial pre- and post-planting shading was examined to determine their effects on post-planting shoot and root growth as well as the vigor of one- and two-year-old Norway spruce seedlings. Three planting experiments were carried out on open nursery fields (Exp. 1, 2) and on a mounded forest clearcut in central Finland (Exp. 3). Before planting, the seedlings were stored over winter either in a freezer or on open fields under snow cover. For two weeks prior to planting, half of the seedlings were placed in the open and the other half under a horizontal shade netting (light transmittance 56 %) (Exp. 1, 2). All seedlings were planted with or without a vertical post-planting shade, which was located on the southern side. Post-planting shading enhanced shoot growth and reduced damage (better visual vigor and needle color and less pine-weevil damage) on Norway spruce seedlings for at least two years after planting (Exp. 2, 3). Those seedlings, that had been stored over winter in the open and kept in shade prior to planting seemed to benefit most from post-planting shading (Exp. 2). However, post-planting shading may give variable results, depending on the seedling quality and weather conditions after planting, and may even reduce shoot growth if no pre-planting shading is used (Exp. 1). Shoot growth may also be improved at the expense of root growth (Exp. 3). The costs of manufacturing and installing post-planting shades may limit their use in practice, for example, to selected regeneration sites where there is high risk of frost damage but where no alternative silvicultural procedure (shelterwood or nurse crop) has been used. 相似文献
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This experiment evaluated the influence of manure, peat, and vermiculite incorporated at low and high rates (0.0118 and 0.0236 m3/m2) and under two soil moisture regimes on Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedling (1+0 for 1+1) xylem water potential (xylem), whole-plant growth, root architectural development, and subsequent field performance under fertilized and non-fertilized conditions. Trends in soil moisture retention were observed (high manure > high peat > control) but there were no differences in xylem. Root length in the wetter soil moisture experiment was initially (three months) greatest for seedlings in high vermiculite and least in high manure but there were no differences among treatments at lifting (eight months). Mean height was greatest for seedlings grown in vermiculite and peat (wetter nursery experiment) after two field seasons. Field fertilization (35 g/seedling) with controlled-release fertilizer in the planting hole stimulated height growth initially, but decreased height and diameter growth during the second growing season. Dramatic improvements associated with the use of nursery soil amendments were not realized, but the failure to identify negative effects, a potential reduction in disease incidence, and improvement of nursery soil physical and chemical properties may justify their use. 相似文献
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Field performance of silver-birch planting-stock grown at different spacing and in containers of different volume 总被引:1,自引:0,他引:1
Silver birch seedlings were grown in two types of trays differing incell volume. For each kind of tray, three different spacings were achieved bygrowing seedlings in all, half or one quarter of the cells. The planting-stockso produced was out-planted at two forest sites and growth followed for fiveyears. Container size had a large effect on seedling morphology and on fieldperformance. Density also had a large effect on seedling morphology, but littleinfluence on performance. The tightest relationship of field performance was tothe mean dry weight of the stems of the planting stock (R2 = 0.94).Mean height and sturdiness index, defined as diameter ÷height, were not correlated with performance. Of the non-destructivemeasurements, mean root-collar diameter was the most closely correlated withperformance. 相似文献
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The field performance of conifer and hardwood species inoculated with different inoculation treatments was evaluated 5 or
3 years after outplanting in the field trials established in the Canadian Prairie Provinces. In conifer trials, the growth
of white spruce, black spruce, lodgepole pine, and larch seedlings observed on different sites varied greatly to different
inoculation treatments depending on plant and fungal species involved. Five years after outplanting, most of the introduced
fungi were replaced by several indigenous ectomycorrhizal fungal species except for Laccaria bicolor strain. Survival rates of most of the inoculated seedlings were not significantly different from control seedlings naturally
colonized by other resident fungi. In hardwood trial, the effects of nursery inoculation of different poplar clones, aspen
and balsam poplar were very limited. Growth and survival data were combined into seedling volume and plot volume index (PVI)
for measurement of total growth response of seedlings. Our results demonstrated that certain inoculated plant-fungus combinations
have played a positive role during the initial establishment of these seedlings in the field, which was reflected on significantly
greater stem volume and PVI compared to non-inoculated control seedlings. The results from this study provided useful information
on field evaluation for potential benefits of mycorrhizal inoculation in nursery. 相似文献
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Research regarding seedling quality issues has been performed for decades and focused primarily on conifer species, which
comprise the greatest proportion of nursery production worldwide. Demand for hardwood seedlings, particularly for conservation
purposes, has increased steadily in recent years, emphasizing the need for seedling quality assessment protocols specific
to these species. Important differences between conifer (gymnosperm) and hardwood (angiosperm) species require the creation
of seedling evaluative programs specific to each group. Variation in phenology and ecological adaptability of hardwood species
limits the validity of inferences made between and within genera. Annual cycles of leaf emergence followed by abscission in
temperate hardwoods necessitate examination of seasonal variation in indicators of physiological condition that do not require
leaf tissue (e.g., mineral nutrition, electrolyte leakage). Also, it is crucial to identify appropriate sampling periods and
plant tissues for testing such that test results may be accurately compared. Though certain parameters (e.g., morphological)
may be readily used in both conifer and hardwood seedling quality testing programs with little modification, additional refinement
is needed to improve predictive capacity for hardwoods across a variety of environments. We review the current state of knowledge
regarding seedling quality testing of temperate deciduous hardwood species, discuss limitations in incorporating traditional
components of quality testing programs, and set priorities for future study. 相似文献
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Deborah S. Page-Dumroese R. Kasten Dumroese Martin F. Jurgensen Ann Abbott Jennifer J. Hensiek 《Forest Ecology and Management》2008
After five years of growth at high-elevations (∼3000 m) in Utah, container lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) seedlings survived well (80–95%) and grew to similar heights regardless of nursery storage method and site preparation technique. Seedlings received one of three storage treatments: (1) spring-sown in the nursery, overwintered in cooler storage and outplanted in July; (2) spring-sown, overwintered in freezer storage, and outplanted in July; or (3) winter-sown, no storage, and hot-planted in late August. We outplanted seedlings at two locations that were clearcut and had received two treatments of surface organic matter (coarse wood, logging slash, and forest floor) removal: surface organic matter (OM) piled with a bulldozer and burned or surface OM remaining in situ. Compared to adjacent uncut stands, both site preparation treatments increased total soil bulk density, but retaining surface OM in situ maintained soil OM, carbon, and nitrogen levels. After one growing season, seedlings planted where surface OM had been bulldozed were taller and had more biomass, although survival was similar (≥96%) across site preparation treatments. The height growth advantage disappeared after five growing seasons and although overall survival was good, survival was highest where site preparation involved removal of surface OM and freezer-stored seedlings were planted. Total non-structural carbohydrates tended to be higher in roots than in shoots and were also higher in hot-planted seedlings than in stored seedlings. Our results indicate that nursery and forest managers have several options for successful nursery production and outplanting of container lodgepole pine seedlings in the central Rocky Mountains. Using hot-planted seedlings allows for a faster turnaround time (from seed to plantable seedling) and maintaining surface OM may be a cost-effective alternative to dozer piling and burning. 相似文献
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