DNR Field Notes
April 7, 2010
Care and Maintenance for Trees
By Chuck Turley
Washington State Forester
Washington State Department of Natural Resources
With spring comes the urge to plant trees in your yard. Before you do, the Washington State Department of Natural Resources (DNR) suggests you make a plan for the care and maintenance of your new tree.
When you plant a tree, you look to the future. In the words of the 19th Century American poet Lucy Larcom, “He who plants a tree, plants a hope.” Diligent care after planting will make sure your hope stays alive.
Make sure the tree can live ‘comfortably’ to maturity in its new accommodations. That includes enough space for roots under the ground, and branches above the ground. (For example, if you have a narrow space, plant a narrow-growing tree.)
Planting correctly can ensure the success of the tree. Take note of the flare of the root – the part of the trunk that widens into the roots. You may need to dig some of the soil away from a nursery tree to find the root flare. Plant the tree so the flare is at, or slightly above, the height of surrounding soil. A tree planted too deep will not get enough oxygen. Moisture against the trunk may cause rot.
Be careful when mowing or weeding because cuts through the bark can damage or even kill a tree.
For healthier, long-living trees, follow these tips:
Watering: Trees lose up to 80 percent of their root systems during transplanting. Help your tree establish and grow quickly by giving it enough water to re-grow its roots. For the first two to three years, a tree needs about 5 gallons of water a week for every inch of trunk diameter. A tree with 1-inch diameter truck needs at least 5 gallons a week, but increase watering in hot or windy conditions. Watch your tree’s ‘body language.’ If leaves wilt, brown at the edges, or display early fall-like coloring, the tree probably needs more water.
Mulching: Mulching keeps tree roots cool and moist which will encourage growth. Mulch also reduces competition from grass and weeds. Mulch should be no deeper than about 4-inches, and should never rest against the trunk of the tree. Use loosely-packed organic material like wood chips, shredded leaves, or pine straw.
Fertilization: Research is inconclusive about the use of fertilizer. Your best bet is to watch for the signs of an unhealthy tree (poor foliage, color, insects or disease) before deciding whether to fertilize. Trees respond best to fertilizers with a higher percentage of nitrogen. Most soils already contain enough phosphorus and potassium, which are the other components of ‘complete’ fertilizers. Check out http://hort.ifas.ufl.edu/woody/ http://treesaregood.org/ for details about fertilizing shade and ornamental trees.
Pruning: Most trees do not need a lot of pruning and should not be pruned until after the first growing season, but some pruning may help young trees. Pruning directs the growth of the tree, keeps it healthy, and prevents future problems with a tree’s surrounding. Over-pruning can kill a tree. Also, never top a tree! Look here for great pruning tips: http://hort.ufl.edu/woody/structuralpruningflash.shtml or look for pruning classes in your area.
Hire an arborist: A certified arborist is a professional who can assist you with tree-care questions, and help you prune and care for your trees. One source is the International Society of Arboriculture with an online directory at: www.pnwisa.org
For additional tree tips, or tree care workshops, contact DNR’s Urban and Community Forestry Program at: 360-902-TREE or firstname.lastname@example.org
EDITOR: A photograph of Chuck Turley is available on request. Graphic art of the recommended root collar is also available
Contact: Janet Pearce, Education and Outreach Manager, 360-902-1122, email@example.com