Salem residents learn about trees
By BROOKS TAYLOR
Mt. Pleasant News
SALEM — Area residents were treated Saturday morning to a program on the planting and caring of trees by Lisa Louck, Iowa Department of Natural Resources district forester.
Louck, whose visit was sponsored by the Friends of the Salem Crew Public library, likened trees to human beings.
“A tree is a life form, and like us, they need adequate water, air and nutrition. Also, like us, if they have a good beginning, they will be healthier and able to resist diseases and plants,” Louck said.
One of the keys to planting success, she said, is planting trees in a good site, one that is well drained and allows for unrestricted growth as the tree matures. Adding mulch around trees increases overall health in many ways — including reducing competition from turf grass.
In tree selection, diversity is a key. Any project with less than 30 trees, only a maximum of three trees per species should be planted. For projects over 30 trees, a maximum of 10 percent per species and 20 percent per genus is the rule of thumb.
For the best shade of homes and buildings, trees should be planted on the east or west side. Enough distance shall be allowed so that trees are not competing with each other for resources. Although it used to be said that a tree’s root system was vertical, it is now known that the root system is horizontal. Typically a root system will be several times the diameter of the mature tree’s dripline. When calculating the planting distance between trees, use the diameters and heights of a mature tree as a guide.
Following are the key points in planting a tree.
• Handle the tree by the root package, not the trunk.
• Find the main root system and remove excess soil down to the top of the main root system (the root collar).
• Dig a hole as deep as the remaining root ball, and as wide as two to three times its diameter. This is especially important if the soil is clay or compacted (e.g. from a drought or recent construction).
• Free the roots and get rid of any potentially encircling roots.
• Once the tree is in the hold, back fill with the original soil.
• Straighten the tree and pu8ll up if necessary to keep the top of the root collar above ground.
• Spread a two to four-inch layer of much over the backfilled area, with mulch at least two inches away from the trunk. Mulch against the trunk of a tree can lead to seriously damaging problems — rot from moisture, encircling roots growing out into the much and a home for rodents or other damaging pets.
• Don’t fertilize immediately after planting. Fertilizer encourages leaf growth. However, the newly planted tree needs to get its roots firmly established. Fertilize later, only if testing shows the soil is nitrogen deficient.
• Stake and prune only if necessary. If the tree will be unstable, stake with a loose material so that the tree can grow without restriction. Prune only if a branch is broken, dead or if there are competitive leaders (main vertical branch). Prune to the branch collar, not flat with the trunk.
Once the tree has been planted is growing, it should be re-mulched annually. However, old mulch should be raked off so that the mulch depth does not exceed four inches. Also, keep mulch away from the trunk of the tree.
A young tree should be watered heavily during its first three years. The best way to determine if watering is needed is to check the soil moisture at six inches below the surface.
Mature trees also need watering because roots are much shallower in diameter than previously though. For a mature tree, water between six feet of the trunk and the dripline (an area equal to the tree diameter when in full leaf).
Louck also talked about the emerald ash borer (EAB), which has been found in several Iowa counties including Des Moines County. Imported from Asia, the EAB causes the primary damage to ash trees when in the larval stage, which feeds on the bark and wood fiber, cutting through the phloem. The phloem of the tree is the channels that carry nutrients from the roots of the trees.
There is treatment for EAB, but it is expensive. Early spring is the only effective treatment period. Louck said it was a waste of money to treat for EAB in the fall.
Unfortunately, there are no treatments on the market that are a one-and-done cure-all. The tree will be needed to be treated every one to three years depending on the product used. Injection treatments will damage the vascular structures in the tree so treatment should not be started before the infestation is discovered in your community.
For more information on the planting and caring of trees, see www.treeownersmanual.info.