Trees are a gift that are given to us, usually by someone with vision, from a previous generation that had a desire or some plan that a certain tree or trees would look nice and be beneficial in a certain place. As they tower above us with their beauty, providing shade and shelter from the public as well as the elements, we give them little thought, until they are gone. Then we mourn them like losing an old friend. Most of us, as we think back through our life, can think of trees that were great, whether it be for beauty, protection, or climbing. The June 17 tornado took many of these towering beauties. You can rebuild a building, but it will take almost a lifetime to grow a good-sized tree.
The Wadena Soil and Water District has planned an opportunity to purchase bare-root trees this fall at a reduced cost (like they also do every spring) to help replace trees lost in this tornado. So I want to write about some factors to consider when planting trees. The first is that transplanting is a shock. Whether the tree is bare-root, balled and burlapped, containerized, or dug with a tree spade, all these trees have had a large amount of their root system cut off and lost. This causes transplant shock. Even if healthy and correctly planted, they must recover from the shock of transplanting before they can live long, healthy lives. The tree has to regenerate its root system and may need to become acclimated to a new soil type. Although the tree may put out new leaves, it usually will not grow normally while in shock. Larger trees take longer to recover from transplant shock than smaller ones or seedlings. The fact is that the tree will not grow on top until it has recovered its root system under the ground. A rule of thumb is to allow at least one year of recovery per inch of stem diameter. So if you have a two inch stem, it will be at least two years before you will see any tree growth other then leaves, above ground.
Digging the hole for bare-root tree is the first important step in transplanting. The hole should be at least 1 to 2 feet wider than the size of the root system. The larger the hole the better the opportunity for root growth. Roughen the sides of the hole with a shovel to make the hole wide or wider at the bottom than at the top, so the roots can be spread out. Make a mound in the middle of the hole on which to place the tree (the root collar should be at ground level) and spread the roots down and around this mound. Place the tree in the hole so the largest branches are facing southwest. Cover the roots with soil and gently raise and lower the plant while adding soil to eliminate air pockets. When the hole is three-quarters full, tamp the soil and fill the hole with water. This should take care of any remaining air pockets. Finish filling the hole and water thoroughly.
It is not advisable to fertilize trees when they are planted because the fertilizer may burn the roots. If you want to add some soil amendments like compost or loamy top soil it is OK; however, too much soil amendment can create moisture gradients and cause roots to be confined to the planting hole. One important adjustment a tree has to make is to the soil type in which it is planted, so that the roots can continue to grow outward and anchor the tree.
Mulch around the base of the tree. Mulching plants makes a more favorable environment for the roots. A mulch allows better infiltration of water, holds soil moisture, limits weed growth, and discourages injury from lawnmowers and weed whips. A good mulch is 3 to 6 inches thick, spread to form a 3 to 6 foot diameter circle around the tree. The mulch material should not come in contact with the tree trunk, but be pulled back 3 to 4 inches in a circle around the trunk. Wood and bark are good mulch materials. A porous landscape fabric or newspaper (at least four layers thick) allows gas and water exchange for the roots. Plastic under mulch can cause roots to suffocate and is not recommended.
Watering is especially important the first few years of a trees life. If rain is not adequate, 5 to 7 gallons of water applied to the root ball once a week is necessary. If it is hot and windy, or if the soil is sandy, this amount may need to be added more often.
Newly planted trees will do better without staking. Young trees standing alone with their tops free to move will develop stronger, more resilient trunks than those staked for several years. Trunk movement is required to develop strong, tapered trunks. However, a tree that is unstable in a strong wind or is pushed over, will require staking. Soft nylon webbing or carpet strips attached by grommets to a stake can reduce damage to the tree. Whatever material is used it should allow for some movement. Remove the stake and ties once the tree is established -- usually after one year.
Kyle Schulz is a Wadena County Master Gardener from Sebeka, and the regular gardening columnist for the Wadena Pioneer Journal.