Trees are struggling. It’s a problem all over, said Rachel Allison, district forester for the Nebraska Forest Service, stationed in North Platte.
Many, if not most, trees are planted too deep, she said, and that sets them for problems throughout their lives. Another problem is the way people mulch their trees. Sometimes people buy trees that are not suited for the areas where they will be planting, too, she said.
Allison, along with local Arborist Lynn Fitzgerald donate their time to prune and care for trees in the median on Burlington Boulevard.
Many of the trees have multiple, competing leaders. The leader is the upward-growing branch that forms the center of the crown of the tree. Some are misshapen in other ways. Allison and Fitzgerald are pruning and staking to try to correct the problems. Re-shaping a tree is a gradual process that can take 10 years to accomplish, Allison said. If too many of the leaf-bearing branches are removed in one year, the trees are not able to produce enough food to grow and thrive.
There would be fewer problems to correct if all the trees had been planted correctly. People love trees, and they try, but they just don’t understand, Allison said. She pointed to the bases of some of the trees, noting that the stems (trunks) do not flare out at the ground. That “telephone pole” appearance is a sign of planting too deep, she said.
Trees need oxygen, Allison said, and oxygen content drops sharply from the top inch of soil going down only a few inches, so deeper planting deprives them of that important need.
Fitzgerald said he plants a tree so the upper main root is at the surface of the ground.
“You don’t want to get the bark portion of the trunk underground,” said Paul Huebner, co-owner of Huebner’s Nursery, Lawn and Garden Center. “Sandy, loamy soil is a little more forgiving,” but proper depth is important for any soil type.
Some of the trees that Alison and Fitzgerald are working with have circling roots that are starting to grow over and inhibit other roots. That problem often starts while the tree is still in the pot; the developing roots hit the edge and cannot continue to grow outward.
“Our advice is to score the roots” after taking the tree out of the pot and before planting it into the soil, Huebner said.
He uses a pruning tool or sharp knife inserted about ½- to ¾-inch from the outside edge, into the root mass. He cuts from the top to the bottom, in four to six places around the root mass.
“Sometimes you have to cut an x across the bottom” of the root mass, too, so new roots will grow outward and downward as they should, he said.
After planting, a layer of wood mulch, placed on the soil around the tree, helps provide a good growing environment for the roots, Allison said.
“Mulch the soil, not the tree,” she said.
Mulch piled against the stem can keep the bark of the tree moist, encouraging insect feeding and rotting.
Huebner said grass from the lawn may creep into the mulch over time. He recommends spraying the invading grass at the edge of the mulch, as needed, with glyphosate (Roundup) herbicide. Follow labeling directions carefully and do not get the herbicide on the lawn or the tree.
Stake the tree, if necessary, when it is planted, Huebner said. Use a wide material that will not cut into the bark, and avoid pulling it too tight. The purpose is to keep the root mass from rocking in the soil, not to prevent the stem and branches from swaying in the wind.
Huebner said that, even before planting, choosing the right tree is important.
“We sell like 105 varieties of trees, not counting evergreens,” he said. “They all grow in some part of our trade area,” but “people come from 100 miles and there’s a variation,” even in hardiness zones across the region.
A tree that grows well in North Platte may not be suitable for the Sandhills further north. Even within the city, soil conditions vary. Other considerations are matching the mature size of the tree to the available space, the water requirements of the tree, wind tolerance, etc.
Selection depends on personal preference, too. For example, “Some people just love lindens and some people wouldn’t have one,” he said, because they think lindens are too messy.
“There are no perfect trees,” Huebner said.
People need to be aware of their drawbacks as well as their fine points, and care for them so they will be the best they can be.