Eastern white pine trees are a fast growing, long-lived species. They’re native to northern Illinois, but you’ll find them throughout the state. And even though they are “evergreen,” they do go through changes in the fall.
Ken Johnson is a horticulture educator with the University of Illinois Extension. He said that if you notice a large amount of needles beneath your white pine trees, or any pine, don’t be alarmed. That’s the seasonal needle drop.
"White pines -- evergreens in general -- conifers, pines, spruce, cedar, stuff like that -- they're all going to drop their needles at some point in the fall, just like our deciduous trees," he said. "It's primarily environmental."
Johnson said the shorter days and the cooler temperatures trigger seasonal needle drop.
"It's just a response to fall conditions," he said.
Johnson said pine trees start dropping their inner needles -- the ones closes to the trunk, from top to bottom -- when they are two or three years old. It's a sign of good health.
To help the trees maintain their health, now is a good time to make sure they have adequate water to survive the winter.
"Particularly this year," he said, "because a lot of parts of the state are getting into drought conditions. So water the trees now because once the soil freezes, they won't be able to take up water anymore."
Johnson also said that mulching will help the trees retain moisture and prevent "winter burn." That's when the needles run brown or look bleached from a lack of water.
Healthy white pine trees can live about 200 years and grow up to 80 feet tall. Their needles are soft, so it doesn’t hurt to touch them. When they are young, they are often used as Christmas trees.
"They have those blue-green needles and look relatively full compared to others," he said. "But one of the drawbacks to white pines is their branches are kind of pliable, so if you have real heavy ornaments, white pine probably is not going to be the best."
If you don’t chop them down, white pines can live about 200 years while providing a good windbreak, a place for kids to climb and a place for wildlife to live.
If you are interested in planting a white pine tree, they will do well in the northern part of the state. Johnson said northern Illinois is on the southern border of the range where white pine trees flourish.
"They tend to like soils that are a little more coarse, a little more loose," he said. "They kind of like soils that have a little more sand and silt in them than clay. They also don't really like real hot, humid conditions during the summer so they're more restricted to northern Illinois."
Johnson said, "Theoretically, you can plant white pine trees as long as the ground isn't frozen." But, he added, "At this point in the year, it's probably best to wait until spring."
For now, fall is a great time to give them a trim, a good soak and tuck them into a bed of mulch.