Showing 241 – 250 of 351 matching resources
For several years, PMRC researchers conducted research on the collection of sap from small-diameter maple trees. This document outlines the basic concepts, techniques, and applications of this type of sap collection.
Explains how sap flows in trees and the impact that tapping has on subsequent years’ sap flow.
How does a tree respond to the wound created by a taphole, and what does that mean for future sap production?
In 1974 the Vermont Experiment Station, Proctor Maple research team, and the Northeastern Forest Experiment Economics Research Unit at Burlington, VT, launched an intensive 4-year processing research program. This program was designed to accomplish two major goals: (1) increase the efficiency of the conventional open-pan evaporator system from approximately 65 percent to approximately 80 percent; and (2) evaluate new evaporator systems for processing maple syrup products. As an initial part of the first research objective, the energy balance of the conventional open-pan evaporator has been completed. Also, design and laboratory and field testing of a sap preheater system has been completed.
Changes in the amount of sugar in maple sap vary within a sap run, from day to day, throughout the season, and from year to year.
The effects of tapping on trees, and how to avoid overtapping.
Some maple sap producers have wondered whether they could increase the total sap yields by tapping their trees not only in the sprint but also in the fall too. Our research indicates that tapping in the fall cannot be recommended.
In March and April 1983, 289 and 196 young grafted sugar maple trees were tapped and evaluated for sap-sugar content. In April, sap was collected from taps both above and below the graft union. Diameter of all tapped trees at 18 inches above the ground was measured. Analysis of the data revealed that: (1) trees selected for high sugar yield cannot be reproduced by grafting on rootstock of unknown but varying sugar content without encountering large fluctuations in sap sweetness of the trees produced; (2) diameter is not correlated with sap sweetness of young grafted trees; (3) numerous sap-sugar readings over time may be necessary to identify the sap sugar characteristics of a candidate sweet tree; and (4) the cause of the variation in sap-sugar content of trees over time needs to be investigated more fully.
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.
Nonstructural carbohydrate reserves support tree metabolism and growth when current photosynthates are insufficient, offering resilience in times of stress. We monitored stemwood nonstructural carbohydrate (starch and sugars) concentrations of the dominant tree species at three sites in the northeastern United States. We estimated the mean age of the starch and sugars in a subset of trees using the radiocarbon (14C) bomb spike. With these data, we then tested different carbon (C) allocation schemes in a process-based model of forest C cycling.