Jim Gilbert Leaf-Out Home Page Today's News Spring's Journey North Report Your Sightings Teacher's Manual Search Journey North return to: A/CPB

Leaf-Out Update: March 6, 1998 Today's Report Includes: Leaf-Out News: Dogwood Challenge Question # 2 Leaf-Out News: Redbud Maple Sugaring Update How Old is Your Tree? Challenge Question # 3 Leaf-Out News: Dogwood Lisa Barnard of Benton, LA (32.73 N, -93.62 W) is the first to report leaf-out of a dogwood this spring, on 03/02/98. (jgbar@worldnet.att.net) From of Gainesville, GA, Mark Barton reports: "The dogwoods are close to start leafing out. The stems by the buds are a rich, dark, dark red. They get this way just before they start to sprout leaves. However we have gone from 70F to an estimated 20F tonight, with the prospect of snow." (mmb1984@aol.com) Also from Georgian, Martha Cummings in Blakely, GA observes: "Our dogwoods are just beginning to have small blossoms, but they are not yet the size of quarters. We're checking them every day or so. By leafing out, do you mean actual leaves or do the white flowers count? The trees will, of course, be filled with blossoms before the actual leaves take over." (pilgrims@sowega.net) 03/02/98 Blakely, GA Good question! We mean leaves, not flowers. Before spring travels any further, let's find out if anyone knows the answer: Challenge Question # 2 "Are dogwood flowers actually leaves or flowers?" (To respond to this question, please follow the instructions at the end of this report.) Leaf-Out News: Redbud Thanks to our Texas observers--and John Wakefield in Florida, for the following leaf-out dates from their region: Date Town St/Pr Lat (N) Long (W) 03/03/98 Houston TX 29.75 -95.36 03/02/98 Houston TX 29.76 -95.36 03/02/98 Houston TX 29.68 -95.36 02/28/98 Orange Park FL 30.13 -81.77 02/15/98 Houston TX 29.75 -95.36 Report the date your TAP your FIRST Sugar Maple tree this spring to Journey North! Maple Sugaring Update It's still too early for leaf-out in the north, but Journey North observers report that the sap has begun to flow in their maple trees. Link to data: First Maple Tree Tapped "This is the earliest we have ever tapped our maple trees in 15 years of sugaring!, reported, Ms. Pace from Wisconsin Rapids East Jr. High in Stevens Point, WI. (cpace@coredcs.com) And unusually warm temperatures in Castleton, NY also resulted in early sap flow according to Maple Hill Middle School: "In our region the average temperature for February is 23.8F. The average temperature for February, 1998 was 30.8F. Many people are predicting that the maple sugar season will be very short with disappointing yields." (jmonteau@albany.net) "We found out that it takes 40 gallons of sap to make one gallon of maple syrup!," said Lebanon Elementary School 3rd graders in Lebanon, CT. "We have 4 trees in front of our school and the sap is running in all of them. It is clear and sticky, not brown like the maple syrup you buy in the store." (lisa.gamache@lebanonct.org) "The night frost combined with 50 degree temps provided the perfect day for tapping and collecting sap," began Ms. Conrad of Auburn, IN. "Two second grade classes from Waterloo Elementary opened the sugaring season today at the Merry Lea Environmental Learning Center's sugarbush between Fort Wayne and Garrett, Indiana." (ldconrad@locl.net) What's Happening Inside the Sugar Maples Now? Here's Vermont forester Paul Cate's explanation as to why sap runs in the spring: "Actually, sap flows anytime when the trees are dormant (not growing) and there are sufficient temperature fluctuations above and below freezing. Trees could be tapped in the fall but the sap tends to be about half as sweet as in the spring. "In spring the thawing days, 40-45 degree temperatures cause an expansion of gases (CO2) and sap. This creates pressure in the tree and the consequent runs of sap from any tap holes. Below freezing nights cause a contraction of the gases and sap, and a pressure reduction in the tree. So, sap will flow whenever pressure in the tree is greater than the atmospheric pressure. "Starch stored in the wood cells is not readily changed to sugar by enzymes until the wood temperature reaches 40 degrees. Between 40-45 degrees the starches change to sucrose and go into solution in the sap. Above 45 the enzymes no longer convert starch to sugar. This explains why early and late runs of sap are usually not as sweet as the midseason runs. The starch-to- sugar change begins the process of breaking dormancy, preparing the buds to open and the leaves to expand." "Maple sap run was front page news in The Toronto Star today," said Don Davis . "There is concern for an abnormally short sap run; that trees will bud early and stop producing sap if the warm temperatures continue. One fellow held a cell phone to a tapped tree and heard sap coming out in a stream, fast and furious! Across the province of Ontario, there are many Maple Syrup Festivals." (Donald_Davis@stubbs.woodsworth.utoronto.ca) Link to Maple Sugaring Spring Phenology Chart How Old is Your Tree? Challenge Question # 3 "How could you estimate the age of your tree, without cutting it down to count its rings?" Think about this question. What other ways could you measure your tree to get a good indication of its age? In our March 20 update we'll share a method used by foresters. Help Track Spring We hope you'll help us measure spring's northward journey by reporting when leaves emerge on your trees. When the leaves on your adopted tree are the size of a quarter (our definition of "leaf-out"), report to Journey North. Simply press the Owl Button and a Field Data Form will appear. How to Respond to Today's Challenge Questions 1. Address an e-mail message to: jn-challenge-leaf@learner.org 2. In the Subject Line of your message write: Challenge Question # 2 (or #3) 3. In the body of the message, give your answer to ONE of the questions above. The Next Leaf-Out Update will Be Posted March 20, 1998. Copyright 1998 Journey North. All Rights Reserved.