How to Plant a Tree
Fall is a great time to plant trees, said a University of Illinois Extension horticulture educator.
"Nearly all of Northern Illinois have seen the decline and loss of ash trees from the Emerald Ash Borer or the drought of 2012," said Richard Hentschel. "The 2013 growing season has been good for many plants including trees. The longer cooler spring with above average moisture has been great. There are many other species of trees to choose from. This is also that opportunity in our yards to consider where the new tree will be planted and how big of a tree we want when it is mature."
Once size, location, plant characteristics have been decided, another decision is needed-- planting the tree yourself or having the tree planted by the nursery. "How much the tree weighs is often the deciding factor for a homeowner," he said. "Trees can be found in large pots with an artificial soil and weigh far less than the same tree offered as a balled and burlapped tree. One limitation to a potted tree will be the sizes available. If you are looking to replant with a larger caliper tree then you most often going with a balled and burlapped plant."
Regardless of how the tree sits in the pot or looks like being balled and burlap, there is a critical spot on the trunk that should be found before you even dig the hole. This is the flare area where the trunk begins to turn into the root system. On larger trees this flare is more readily apparent. On smaller trees you will have to clear away the soil in the pot or top of the ball to be sure you know where this flare is. Even on a larger balled and burlapped tree the flare can be below the top of the ball. What research has shown us is that a tree planted too deep is slow to recover from being transplanted and has more problems in the future with insects and disease.
"Once you determine where the flare is, then dig the hole so the flare will be at the soil line or even an inch or two above that," Hentschel said. "If you do not have great drainage, then above the soil line is suggested. Roots will naturally grow down into the soil profile to a depth where they find a balance of soil moisture and air for quickest transplant recovery and long term growth."
Once you are ready to set the tree in the planting hole, there are a few more things you can do to ensure your tree will establish easily. For a tree that has been grown in a pot, there will be some roots that have found the edge of the pot and are now circling. These roots need to be bent outward as you backfill the hole. If they cannot be bent out, pruning them away is the alternative. Any new roots that grow from the cut will grow out normally.
For balled and burlapped plants and those with a wire basket there is a different strategy. "Once the ball is in the planting hole remove some of the basket and burlap and twine," he explained. "Burlap and twine may not be entirely natural and rot away as in the past. Twine will need to be removed from around the base of the trunk and burlap down over the sides of ball as far as possible. That wire basket should be removed down over shoulder of the ball too, leaving room for those expanding roots to develop. You can use the remaining portions of the wire basket to tie more twine up and over the ball, just not around the trunk to help stabilize the tree in the new hole."
The final steps will be to back fill with your soil up about two-thirds, then water to settle the soil around the root ball. Finish back filling and water to settle that soil. With any remaining soil, you can create a berm for watering the rest of the fall. The berm will retain the water and keep it where the roots are, right in the area of the ball or pot.
"Monitor and water until mid-November to be sure the newly planted trees have ample water," he noted. "Before freezing temperatures get here, cut a couple of spots out of the watering berm so water will not stand and harm the tree trunk."