Skip to main content

Possible online services disruption due to Internet related outage

A worldwide technology outage is causing disruption to some State of Illinois online systems.  We are aware of this issue and are diligently working on restoration.

Big Tree Programs

Winners of the National Big Tree Program at American Forests by American Forests; 3:23 minutes; Discusses the 700 national champion trees designated through the National Big Tree Program administered by American Forests.    


American Forests Big Tree Measuring Workshop Part 1: Crown Spread  by American Forests; 55:16 minutes; Crown spread is often the first sign of a tree's size. This webinar will cover the two-diameter method, spoke method and common obstacles when measuring crown spread.


American Forests Big Tree Measuring Workshop Part 2: Circumference by American Forests; 1:20:53 minutes; In Forestry, the girth of a tree is measured as diameter breast height (DBH), or 4.5 feet above ground level. This webinar will teach you how to measure the girth of a tree on a flat surface, a tree on sloping ground and a tree that leans. 


American Forests Big Tree Measuring Workshop Part 3: Height by American Forests
; 1:02:05 minutes; National champion trees may be 30 feet tall or 300 feet tall. From the red maple in your backyard to the eastern white pine in an old-growth forest, this webinar will show you the most effective techniques to accurately measure the height of trees for all skill levels.