Initial spacing influences 20-year growth and development of red alder

A two-staged stand growth model is developed to describe the relationship between biomass or volume and numbers of stems in even-aged, monospecific plant populations undergoing self-thinning. The model is tested on red alder (Alnusrubra Bong.) seedlings and red pine (Pinusresinosa Ait.) stands grown over a range of site qualities and initial spacings. First, survival rate is modelled as a Weibull distribution. This is then fit to an analytical size–density model to give growth estimates. Crown closure is estimated to occur at a relative density of 0.09 for red alder, while initial mortality is estimated to occur at a relative density of 0.12 for red pine. Net stand growth rates peaked at a relative density of 0.54 for red alder biomass and from relative densities from 0.40 (widest initial spacing) to 0.55 (densest initial spacing) for red pine total stem volume. Site quality merely shifted the magnitude of these relationships. The model adds a dynamic component to the self-thinning rule and also generalizes and extends the rule to stand development between crown closure and the self-thinning asymptote.

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Growth and development of red alder compared with conifers in 30-year old stands /

10.5962/bhl.title.81530 ◽

1961 ◽

Cited By ~ 4

Author(s):

Carl M. Berntsen ◽

Keyword(s):

Growth And Development ◽

Red Alder

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Density and rectangularity of planting influence 20-year growth and development of red alder

Canadian Journal of Forest Research ◽

10.1139/x02-040 ◽

2002 ◽

Vol 32 (7) ◽

pp. 1244-1253 ◽

Cited By ~ 9

Author(s):

Dean S DeBell ◽

Constance A Harrington

Keyword(s):

Tree Growth ◽

Growth And Development ◽

Tree Height ◽

Planting Density ◽

Alnus Rubra ◽

Stand Development ◽

Red Alder ◽

Management Guidelines ◽

Stand Characteristics ◽

Related Mortality

Red alder (Alnus rubra Bong.) seedlings were planted in northwestern Oregon, U.S.A., at five initial spacings: 0.6 × 1.2 m, 1.2 × 1.2 m, 1.2 × 1.8 m, 1.8 × 1.8 m, and 2.5 × 2.5 m. Up to about age 10, tree and stand characteristics were correlated primarily with initial planting density in the expected manner; through age 20, however, tree growth and stand development in plots planted at rectangular spacings were substantially more rapid than in the two closest square spacings. Mean stand diameter ranged from 19.2 cm in the widest spacing to 14.0 cm in the closest square (1.2 × 1.2 m) spacing; mean tree height decreased from nearly 24 m in the widest (2.5 × 2.5 m) spacing to about 18 m in the closest square spacing. Diameterdensity relationships in the widest spacing were consistent with existing density management guidelines, but very dense spacings and rectangular plantings began to experience substantial mortality at smaller diameters than assumed in the guidelines. We suggest that rectangular planting of red alder at dense spacing enhanced stand differentiation, accelerated competition-related mortality, and thus led to improved growth of surviving trees.

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An ultrastructural study of vegetative incompatibility in plants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083047 ◽

1978 ◽

Vol 36 (2) ◽

pp. 436-437

Author(s):

Randy Moore

Keyword(s):

Ultrastructural Study ◽

Cell Walls ◽

Growth And Development ◽

Solanum Pennellii ◽

Initial Product ◽

Basic Aspect ◽

Tissue Interactions ◽

Graft Interface ◽

Antigen Antibody ◽

Standard Fixation

Cell and tissue interactions are a basic aspect of eukaryotic growth and development. While cell-to-cell interactions involving recognition and incompatibility have been studied extensively in animals, there is no known antigen-antibody reaction in plants and the recognition mechanisms operating in plant grafts have been virtually neglected.An ultrastructural study of the Sedum telephoides/Solanum pennellii graft was undertaken to define possible mechanisms of plant graft incompatibility. Grafts were surgically dissected from greenhouse grown plants at various times over 1-4 weeks and prepared for EM employing variations in the standard fixation and embedding procedure. Stock and scion adhere within 6 days after grafting. Following progressive cell senescence in both Sedum and Solanum, the graft interface appears as a band of 8-11 crushed cells after 2 weeks (Fig. 1, I). Trapped between the buckled cell walls are densely staining cytoplasmic remnants and residual starch grains, an initial product of wound reactions in plants.

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Identification of calcium oxalate crystals in dried or fixed tobacco leaf

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111550 ◽

1984 ◽

Vol 42 ◽

pp. 288-289

Author(s):

Vicki L. Baliga ◽

Mary Ellen Counts

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Calcium Oxalate ◽

Growth And Development ◽

Polarized Light ◽

Calcium Oxalate Crystals ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

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SEM study of the morphological effects of kinetin and zeatin on the growth and development of the apical meristem in wheat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141263 ◽

1995 ◽

Vol 53 ◽

pp. 978-979

Author(s):

G. M. Hutchins ◽

J. S. Gardner

Keyword(s):

Growth And Development ◽

Furfuryl Alcohol ◽

Apical Meristem ◽

Plant Cells ◽

Triticum Aestivum L ◽

Morphological Development ◽

Naturally Occurring ◽

Chinese Spring Wheat ◽

Sem Study ◽

Moist Environment

Cytokinins are plant hormones that play a large and incompletely understood role in the life-cycle of plants. The goal of this study was to determine what roles cytokinins play in the morphological development of wheat. To achieve any real success in altering the development and growth of wheat, the cytokinins must be applied directly to the apical meristem, or spike of the plant. It is in this region that the plant cells are actively undergoing mitosis. Kinetin and Zeatin were the two cytokinins chosen for this experiment. Kinetin is an artificial hormone that was originally extracted from old or heated DNA. Kinetin is easily made from the reaction of adenine and furfuryl alcohol. Zeatin is a naturally occurring hormone found in corn, wheat, and many other plants.Chinese Spring Wheat (Triticum aestivum L.) was used for this experiment. Prior to planting, the seeds were germinated in a moist environment for 72 hours.

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Mechanisms of ethylene biosynthesis and response in plants

Essays in Biochemistry ◽

10.1042/bse0580061 ◽

2015 ◽

Vol 58 ◽

pp. 61-70 ◽

Cited By ~ 11

Author(s):

Paul B. Larsen

Keyword(s):

Plant Growth ◽

Growth And Development ◽

Ethylene Biosynthesis ◽

Unsaturated Hydrocarbon ◽

Flower Senescence ◽

Detailed Knowledge ◽

Plant Growth And Development ◽

Step Process ◽

Ethylene Response ◽

Ethylene Signalling

Ethylene is the simplest unsaturated hydrocarbon, yet it has profound effects on plant growth and development, including many agriculturally important phenomena. Analysis of the mechanisms underlying ethylene biosynthesis and signalling have resulted in the elucidation of multistep mechanisms which at first glance appear simple, but in fact represent several levels of control to tightly regulate the level of production and response. Ethylene biosynthesis represents a two-step process that is regulated at both the transcriptional and post-translational levels, thus enabling plants to control the amount of ethylene produced with regard to promotion of responses such as climacteric flower senescence and fruit ripening. Ethylene production subsequently results in activation of the ethylene response, as ethylene accumulation will trigger the ethylene signalling pathway to activate ethylene-dependent transcription for promotion of the response and for resetting the pathway. A more detailed knowledge of the mechanisms underlying biosynthesis and the ethylene response will ultimately enable new approaches to be developed for control of the initiation and progression of ethylene-dependent developmental processes, many of which are of horticultural significance.

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The Fundamentals of the Clinical Fellowship Experience

Perspectives of the ASHA Special Interest Groups ◽

10.1044/persp1.sig11.81 ◽

2016 ◽

Vol 1 (11) ◽

pp. 81-85

Author(s):

Melanie Hudson

Keyword(s):

Growth And Development ◽

Transition Period ◽

Clinical Skills ◽

Practical Experience ◽

Professional Experience ◽

New Graduate ◽

Independent Practitioner

The Clinical Fellowship Experience is described by the American Speech-Hearing-Language Association (ASHA) as the transition period from constant supervision to independent practitioner. It is typically the first paid professional experience for the new graduate, and may be in a setting with which the new clinician has little or even no significant practical experience. The mentor of a clinical fellow (CF) plays an important role in supporting the growth and development of this new professional in areas that extend beyond application of clinical skills and knowledge. This article discusses how the mentor may provide this support within a framework that facilitates the path to clinical independence.

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