Made for Shade

April 2019 View more

White oaks are long-lived native trees

By Katie Dubow

If you’re only going to plant one tree this year, I urge you to plant a white oak,” says Charles Shonts, district manager at Naperville’s the Care of Trees. “Besides being our state tree, they are native to Illinois, provide ample shade, offer food and habitat for pollinators, and live a very long time.”

In 1907, almost 1 million Illinois schoolchildren voted for the oak, which was later specified as the white oak, as the official Illinois state tree. While white oaks can live an average of 300 years, even older specimens have been documented.

White oaks get their name from the light appearance of the bark. Oaks provide gorgeous fall color, and on occasion show shades of red, gold, brown, yellow, and purple all on one tree. Plus, oaks support a wide range of animal species, including 534 types of butterflies.

The white oak is as important to people as it is wildlife. Settlers in Illinois used its acorns to feed pigs and its wood to build homes. Today, the white oak is the most common oak in DuPage County and is the dominant tree in most of the county’s forests and woodlands. It provides more value than any other tree.

“In the Chicago region, oaks provide more than $2 billion worth of flood control and other water management services,” says Andrew Hipp, a senior scientist in plant systematics and herbarium curator at the Morton Arboretum. But “today, oaks need our help. With only 17 percent of ancient oak forest area remaining in the Chicago region and similar oak loss throughout the world, human intervention is critical to ensure we don’t lose this important species.”

Planting an Oak

White oaks can grow 80 to 100 feet tall. If given space to spread, the branches will create a massive canopy as wide as the tree is tall, making it an excellent shade tree. Shonts says to pick a spot where your tree will have plenty of room to grow. Make sure the tree is planted at least 20 feet away from above-ground wires, underground pipes or wires, sidewalks, and permanent structures like your home or garage.

The white oak can be found in every county in the state. It grows best in upland areas and on slopes. It is not a tree that grows well in wet soil. Shonts suggests making the planting hole two to three times larger than the root ball to allow the new tree’s roots to spread out. Then position your tree so that the area where the roots meet the trunk is at or slightly above the ground.

After watering, cover the planting hole with two to three inches of shredded hardwood or leaf mulch. Shonts warns: Do not over mulch the tree or “volcano” mulch, keep it two to three inches away from the trunk.

Be sure to provide proper tree maintenance for strong, healthy growth. White oaks are subject to leaf eaters and other bark diseases.

Photo courtesy the Care of Trees