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Sugar Maple Ecology and Health: Proceedings of an International Symposium

During the past four decades, declines of sugar maple have occurred throughout its range. Each decline event has been the subject of intense research.The declines were ephemeral, preventing a complete understanding of conditions and causes.The most recent decline in Pennsylvania was the impetus to organize an international symposium on sugar maple ecology and health. Speakers from the United States and Canada were invited to share their research and explore a variety of topics concerning sugar maple history and ecology, recent sugar maple declines, nutrient and beiowground dynamics in northeastern forests, and interactions of forest health with biotic and abiotic stressors. Posters also were contributed. Attending scientists, natural resource professionals, and land managers participated in two days of talks and discussions and a day-long field trip to sugar maple decline research sites in northwestern Pennsylvania and southwestern New York.

Effects Of The Use Of Paraformaldehyde (PFA) Sterilising Pellets On Sugar Maple Health: A Review

Higher and wider discoloration, compartmentalisation and decay in maple wood by the use of the PFA pellet restricts the healthy sapwood areas and diminishes translocation of sap and nutrients. Furthermore, technological advances for better sanitation in sap collection and storage presently in use by the maple industry, tested by research to be safe for maple tree health and syrup quality, have made the use of the PFA pellet unnecessary.

Vigor and Nutrition vs. Sap Sugar Concentration in Sugar Maples

Although maple dieback has received considerable recent attention in the Northeast, little has been reported about the relationship between sap sugar yield and crown health or crown nutrition. We measured sap sugar concentration (sweetness) in six northern Vermont maple stands in the springs of 1990-1992, and sap volume yield from tapholes at one stand in 1991. The stands differed in average crown dieback, canopy transparency, density, and mean dbh, as well as cation exchange capacity (CEC) of upper soil horizons.

Sapstreak Disease of Sugar Maple: Development Over Time and Space

Sapstreak disease is a potentially serious problem of sugarbushes and forest stands. It is caused by the fungus Ceratocystis virescens, which invades sapwood of roots and bases of stems through wounds created during logging, saphauling, or other activities. This report describes the results of observations and experiments to learn more about the patterns of disease development and the factors that affect them, within individual trees and within representative forests and sugarbushes.

Photographic Guide of Selected External Defect Indicators and Associated Internal Defects in Sugar Maples

To properly classify or grade logs or trees, one must be able to correctly identify indicators and assess the effect of the underlying defect on possible end products. This guide assists the individual in identifying the surface defect indicator and shows the progressive stages of the defect throughout its development for sugar maple. Eleven types of external defect indicators and associated defects that are particularly difficult to evaluate are illustrated and described.

Height-Diameter Relations of Maple Street Trees

Height and diameter measurements were taken for silver, sugar and Norway maple street trees in Rochester and Syracuse, New York.

Sugarbush Management: A Guide to Maintaining Tree Health

Many pests and other stresses affect maple trees growing in a sugarbush. Some pests can markedly reduce sap quantity; others, although conspicuous, are not important. Stresses can result from activities by people and from natural phenomena. Recognizing problems and understanding the factors that contribute to their occurrence, development, and significance are necessary to maintain tree health. This report brings together current information on the living agents and nonliving factors that can cause problems in sugarbushes. Insects, diseases, improper forest stand management, and unwise sugaring practices are illustrated. and ways to prevent or reduce their effects are described.

“Salty” Syrup from Roadside Sugar Maples in Decline

We had two objectives in the study of sugar maples which showed signs of decline and stress on a roadside where deicing salt was used in the winter. One goal was to determine if tree stress is related to the levels offsodium and chloride in their sap and in the groundwater and soil around their roots; and, if so, to develop methodology approved by the Association of Official Analytical Chemists (AOAC) that would allow any laboratory to use a standard method to assess maple tree decline due to sodium and chloride effect. The second goal was to evaluate the quality of the syrup processed from sap aseptically collected from maples in decline. We are updating here the later objective of the project that is of interest to the sugar maple producers.

Timing of defoliation and its effect on bud development, starch reserves, and sap sugar concentration in sugar maple

Sapling sugar maple (Acer saccharum Marsh.) trees were defoliated artificially at 10-day intervals beginning May 27 and ending August 5, 1981. Refoliation, terminal bud and shoot development, and xylem starch and sap sugar concentration were observed in defoliated and control trees. All defoliated trees refoliated, but decreasingly with later defoliation. Defoliation caused an acceleration in the rate of primordia initiation in terminal shoot apices. After early season defoliations, the developing buds in the axils of the removed leaves abscissed, but axillary and terminal buds on the refoliated terminal shoots survived through winter. In late season defoliation, most buds of refoliated shoots did not survive and the next year’s growth depended on axillary buds formed prior to defoliation. Thus, when progressing from early to late defoliations, the next year’s shoot growth depended decreasingly on the last-formed and increasingly on the first-formed portions of the previous year’s shoot. Early October starch concentration in xylem decreased with later defoliation and was nearly absent in shoots and roots of trees defoliated in late July. There was not, however, a corresponding decrease in sap sugar concentration. Mortality occurred only in late defoliated trees and was associated with starch depletion.