We are gearing up for our February Nature Night on A History of Trees—Fire, Old-Growth, and Forest Restoration in Central Oregon! Our speakers, Dr. James Johnston and Dr. Andrew Merschel, use dendroecology in their research, so we’re taking a glimpse into the science of this field with four facts about dendroecology:

1. Dendroecology is the study of ecological and environmental changes depicted in tree rings. It uses tree ring analysis to understand the influences on the tree itself. This includes studying widespread outbreaks of insects in forests, tree decline, and potential changes caused by rising carbon dioxide levels.
2. Dendroecology provides a way to understand longer time periods than we humans can observe. Tree rings not only tell us the age of a tree (letting us look back at hundreds and in some cases, thousands, of years), but they also illuminate what the weather was like during each year of the tree’s life. Examples of this include having smaller tree rings during cold or dry years versus having wider tree rings during warm or wet years. With this weather data, scientists can understand the overall climate of the area during longer time frames.
3. Certain trees are easier to analyze than others. For example, alder and pine can sometimes “skip” a year of tree ring growth or even have two rings in the same growing season! Other tree species, like willow, aren’t used in dendroecology at all, since they have erratic growth patterns. In addition, trees in the tropics are more difficult to analyze because they don’t necessarily have distinct rings of growth. Meanwhile, oaks are incredibly valuable for study because they are very reliable with their annual growth rings.
4. Dendroclimatology is the study of trees as a recorder of the earth’s climate. A sub-group of dendroecology, dendroclimatology really focuses in on climate. Research in this field helps us learn about temperature changes, precipitation variations, and climatic events like El Niño.

We’ll be talking about dendroecology and more on February 21^st. Join us for this free Nature Night—you can register online to attend at the Tower Theatre in Bend or via livestream.


Sources:

• What Can Trees Tell Us About Climate Change?, NASA Climate Kids
• Dendrochronology, Dendroecology, Dendroclimatology… and a Bit about Volcanic Eruptions, Charlotte Pearson presentation, Cornell Tree Ring Laboratory
• A Brief Introduction to Dendroecology, University of Arizona Laboratory of Tree-Ring Research

Learn more:

• East Cascade Dry Forests
• Plant Profile: Ponderosa Pine (Pinus Ponderosa)