Jim Gilbert

Leaf-Out Home Page

Today's News
Today's News
Spring's Journey North
Spring's Journey North
Report Your Sightings
Report Your Sightings
Teacher's Manual
Teacher's Manual
Search Journey North
Search Journey North
return to:
JNorth Home Page



Leaf-Out Study Begins Today: February 6, 1998

Updates Will be Posted on FRIDAYS:
Feb. 6, 20, Mar. 6, 20, Apr. 3, 17

Today's Report Includes:

How to Participate in Journey North's Leaf-Out Study
We hope you'll help us measure spring's northward journey by reporting when
leaves emerge on your trees. Here's how: Adopt a local tree of one of the following species. Visit your adopted tree on a regular basis. Sketch the buds on the same small branch each time you visit. Watch the bud open, the tree bloom and the leaves emerge. When its leaves are the size of a U.S. (or Canadian) quarter, report to Journey North. That's our definition of "leaf-out".

Maps courtesy of:
Macalester College Geography Department
and students Uriah McKinney and Debbie Bojar

Sugar Maple

Please report to Journey North when leaves on trees of any of these 4 species emerge.

Our definition of "leaf-out"?

Flowering Dogwood


When leaves are the size of a quarter.

Quaking Aspen

Spring Fever: Measuring "Growing Degree Days"
Leaf-out is closely associated with temperature. Spring can be said to be "early" or "late" depending on the date that leaves emerge, and leaf-out dates can vary by as much as a month from one year to the next!

How much heat does it take for leaves to emerge and grow? Try measuring Growing Degree Days and explained in Spring Fever lesson and find out. As you collect daily temperature readings, you'll be able to compare the rate
of leaf growth vs. temperature.

Introducing Journey North's Regional Leaf-Out Coordinators
We live in a huge hemisphere, and our success in tracking spring will depend on contributions from many people. This year, a volunteer network has stepped forward to help in this process. You may receive a personal reminder from these classroom Coordinators when the leaves are about to emerge in your region. Special thanks to Gustavus College student intern Christian Gilbert for spending the cold month of January in Minnesota to coordinate this project! And thanks in advance to these teachers and students for contributing their time:

United States Regional Coordinators
North East Ms. Hawes Class in New York
South Atlantic Ms. New's Class in Georgia
South Ms. Osborne Class in Tennessee
South Midwest Ms. Powel's Class in Ohio
Upper Midwest Ms. Sobotta's Class in Michigan
Great Plains Coordinator Needed *
Mountain Coordinator Needed *
Pacific States Coordinator Needed *
Eastern Canada Ms Conroy's Class in Ontario
Western Canada Coordinator Needed *

* If your class would like to take responsibility for one of these regions, please let us know!

Lessons to be Featured This Spring
During this 4-month study, these lessons will be provided to you on the WWW. As each becomes available they'll be linked from the Leaf-Out Home Page. If you have related lessons you'd like to share with others, please let us know.
  • Maple Sugaring & Phenology
  • How Old is Our Tree?
  • How Tall is Our Tree?
  • Tree Timeline
  • Natural History Journal of Our Tree

The Next Leaf-Out Update will Be Posted February 20, 1998.

Copyright 1998 Journey North. All Rights Reserved.