Turn acorns into oak trees

The following article was published in the Cedar Rapids Gazette on Thursday, February 27, 2025. Reprinted here with permission.

Turn acorns into oak trees, Marion nonprofit urges

Monarch Research Project to create ambassadors for the oak tree

By Bailey Cichon, The Gazette 

Monarch Research Project wants Iowans to know that the acorn is mighty.

“Most people don’t realize that (the oak tree) is a keystone element in the ecosystem,” said Clark McLeod, cofounder of the nonprofit Monarch Research Project, based in Marion. “A keystone is that shaped piece on the top of an arch and when you pull the keystone out, the arch falls. That’s what happens when you lose oaks in your ecosystem.”

Native oak trees can support hundreds of species of caterpillars, which in turn feed the birds. Caterpillars are a staple in the diet of baby birds. Contrast the oak tree with a non-native ginkgo tree, which supports just five species of caterpillars, according to the National Audubon Society. Plus, they are natural air filters, pulling carbon dioxide out of the atmosphere and storing it within tree tissue.

Despite the oak tree’s superhero-like status in the ecosystem, “the oak tree has fallen into a position where it’s not the top pick when people are going out and choosing trees,” McLeod said. But “an oak tree, by far (is) the best tree you can put in.”

After Linn County lost an estimated 1 million trees in the 2020 derecho, Monarch Research Project made it its mission to rebuild. The nonprofit has planted 100,000 native trees in Linn County, distributed 20,000 trees in October 2024 alone. The Monarch Research Project wants to double that total in the next five years.

So how do you get people passionate about planting oak trees? You arm them with acorns and create a special society.

Trees/ Participants to join students on project

The Mighty Acorn Society kicks off this week. Somewhere between 400 and 500 people will be supplied with pots, potting soil, stands and deer protection and can choose four acorns from five native Iowa oak species.

In addition to other members of the public, students from the Trailside Elementary and private Summit Schools will participate: 64 Summit students in grades 2-6 will join, along with 25 fourth- and fifth grade students from Trailside’s Green Team.

“The Acorn Society will rear probably 1,000 trees for springtime planting,” McLeod said. “But most importantly, are going to be working as ambassadors for the oak trees.”

McLeod said he chose the word “society” because it means a group of like-minded people. “And the idea is that this society then interacts with the community. … If it grew to 500 or 1,000, we would overwhelm the community with input,” he said, “and the idea is, when you bring the two together, you actually get a movement within the community.”

RAISE AN OAK TREE ON YOUR OWN

While the Mighty Acorn Society event is full and another event is not planned, McLeod said Iowans easily can raise oak trees from acorns on their own. If you’re looking for what species of oak to plant, take a page out of Monarch Research Project’s book. It consulted with three arborists to decide which species to provide and they landed on Northern Red, Bur, Chinkapin, Swamp White and Pin.

“The Swamp White is probably the easiest, fastest growing of the group,” McLeod said. “Northern Red grows from an acorn very easily. They’re all different.”

Start by picking acorns up when the start to fall from the trees. You can find viable acorns by placing them in water for 24 hours. If the acorn sinks, keep it. If it floats, is cracked or has weevil holes, throw them away. Next, put the acorns in a plastic bag with a moist paper towel. Place it in the refrigerator for a few months, removing it between mid-February and March 1. This is called stratification. Then plant the acorn on its side in an air pruning pot and cover it with potting soil. Keep it out of direct sunlight while the acorn germinates.

“Then you can spritz your shell and keep it moist. Do that a couple times a day,” McLeod said.

According to Monarch Research Project, a tap root will poke out of the bottom of the container by the fourth or fifth week. The tip of root will die off when it is exposed to air.

“You won’t see much above the surface,” McLeod said. “Below the surface, the container is filling with lateral roots.”

Water the acorn every three days, keeping soil moist but not soggy. Keep the seedling at 72 degrees until the seedling emerges. When the trunk emerges, slowly introduce sunlight. When the trunk reaches a half inch to an inch, place it in a south-facing window for half the day. Do this for two days.

Then, you can leave it in the window while leaves emerge. If leaves turn yellow, move it to a window with less-direct sun exposure.

In mid-May, move the pot outside and into the shade for half a day. Repeat this for a few days. This process is called hardening off and allows the plant to adjust to outdoor conditions before it is planted outside about June 1.

When you’re ready to transplant the tree, choose a sunny spot and loosen the soil in a 1-foot diameter, 3 to 4 inches deep. Dig a hole equal to the size of the pot.

After the seedling is removed from the pot, place the seedling in the hole and match the soil level with the surrounding ground. Keep about one-third of the acorn visible but ensure the root is not above the soil line. Mulch around the seedling, and make sure to protect it from wildlife. If it doesn’t rain, water the seedling every three to four days.