Written by Rhonda Ferree, retired horticulture educator
Have you ever noticed how a pine tree changes shape as it ages? On my way to Springfield recently, several old pine trees caught my attention.
Pine trees have distinctively different needle structure than other evergreens. Pine needles are in clusters of 2, 3, or 5 and range from one to several inches long. Pine trees also have distinctive habits. Most pine trees start out pyramidal in youth (Christmas tree-like) and become more round-topped, open, and picturesque with age.
Most of the trees I saw on my Springfield drive were Eastern White Pine (Pinus strobes). This pine has 2 to 4 inch needles in clusters of 5. Needles are slender and soft, giving white pines a soft, pleasant appearance. This is a popular tree to plant, partly because it is one of the fastest growing landscape pines, growing 50 to 75 feet tall in 25 to 40 years. Unfortunately, many have experienced white pine decline in recent years probably due to site, environment, and species requirements.
The white pine makes a very handsome landscape plant. According to Dr. Michael Dirr's Manual of Woody Landscape Plants, a "mature white pine is without equal among the firs, spruces, and other pines." In youth a white pine is a symmetrical pyramid. As it ages, the crown (top) changes to show several horizontal and ascending branches.
Another pine that changes greatly with age is the Ponderosa Pine (Pinus ponderosa). This pine has 5 to 10 inch sharp rigid needles in clusters of twos and threes. This tree grows slower, but still can reach 75 feet in 40 or 50 years. It is a very coarse textured tree. Again, this tree is pyramidal when young, but with time develops a narrow, circular top. As it ages, the lower branches droop very low. Very old trees have a flat top and have no branches for one-half or more of their height.
Ponderosa pines have interesting bark. On young trees the bark is brown-black and furrowed. As it ages, bark changes to cinnamon-red showing through large flat plates.
A third pine with unique characteristics is the Scotch (Scots) Pine (Pinus sylvestris). At one time this was a popular landscape tree, but it has developed some major problems. Today it is most commonly grown as a Christmas tree. Scotch pine has an irregular pyramid shape when young. Soon, however, the lower limbs die and the tree develops a very picturesque, open tree with wide-spreading branches and a flat top. This tree grows slower than other pines.
Unfortunately Scotch pine are extremely susceptible to the pine wilt disease. The disease kills trees very quickly. It will often show up as one dead tree in a row of Scotch pine. If that tree is not removed immediately, the disease slowly moves from tree to tree until the whole row is dead.
There are many more nice pine trees available. Look for picturesque old pine trees the next time you drive around, especially near old farmsteads.
MEET THE AUTHOR
As horticulture educator, Rhonda Ferree inspired citizens in local communities to grow their own food and improve their home landscapes. She focused on high quality, impactful programs that taught homeowners how to create energy-efficient landscapes using sustainable practices that increase property values and help the environment.
After 30 years with University of Illinois Extension, Rhonda retired in 2018. She continues to share her passion for horticulture related topics as “Retro Rhonda” on social media.
ABOUT THE BLOG
ILRiverHort is a blog that helps people connect to nature and grow.