1,759 research outputs found
Biology and Management of White Spruce Seed Crops Reforestation in Subarctic Taiga Forests
Seed production is the most dramatic event in the life cycle of trees
and is the first step in forest regeneration. Embryos of white spruce
are fragile during germination, and they depend on vigorous seeds for
survival and growth. Mortality of white spruce seeds and seedlings is
high in northern forests because climate and microhabitat are often unfavorable
for seed germination and seedling establishment. Large quantities
of high-quality seed are required for natural and artificial regeneration
of white spruce forests at high latitudes.
The first chapter of this bulletin describes the reproductive process
of white spruce and factors that affect cone and seed production and
seed quality. Knowledge of the reproduction cycle and factors that affect
seed production and quality of white spruce is essential for
forecasting and managing seed crops.
Evidence that white spruce is a genetically variable species in northern
forests is summarized in the second chapter. This chapter includes
recommendations for maintaining the gene pool of natural populations
and for seed transfer in afforesting sites that do not have endemic populations.
A procedure for delineating planting zones for adapted seed sources
is described as an alternative for provisional seed zones that only reduce
the risk of maladaptation from long-range seed transfer .
The final chapter outlines steps in harvesting white spruce seed crops
and can be used as a working manual . Practical procedures are described
for evaluating quality and quantity of white spruce seed crops , certifying
the geographic origin of seed parents , collecting cones , and processing
seeds to mainatin viability for many years.
The genetic structure of white spruce and the environment-embryology
relationships that effect seed production and maturation have not been
studied in detail . The need for research in the areas of genetics,
biochemistry, physiology, and ecology is discussed in each chapter. The
results of such research will help to improve seed yields and make the
management of white spruce crops more profitable in Alaska and Yukon
Forecasting Market Index Performance Using Population Demographics
This study attempted to verify claims made by forecaster Harry S. Dent, Jr. It utilized regression analysis in order to determine the correlation between the number of births and the closings on a market index with a specified lag between the input and output variables. While the research was able to develop a model with the factor Dent considers the most important, the predictions based on this model did not completely coincide with the forecasts Dent makes. Furthermore, the research could not confirm the accentuation Dent places on a 46-year lag between predictor and response variables. As an extension, scenarios for Japan, the United Kingdom, and Germany were examined. This analysis could not confirm the hypothesized extension of Dent\u27s theory to other countries
Alien Registration- Thibeau, Alden J. (Enfield, Penobscot County)
https://digitalmaine.com/alien_docs/10154/thumbnail.jp
Shakespeare's kings
Thesis (M.A.)--Boston University, 1931. This item was digitized by the Internet Archive
Game Books for Reading Instruction
Books which contain directions on how to construct and use games for reading skill development are popular with teachers because they contain practical suggestions for classroom activities. There are matters related to the selection and purchase of such books with which the teacher should be familiar; those matters are discussed here
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