Evergreen Arborist
Spring Planting Time
March, 2009
The arrival of spring brings out the gardener in many of us.. The following tips will help to make practical decisions of what and where to plant and to consider a few trees to avoid.
Right Tree for the Right Place
The first step is to size up the planting space. Consider both the soil rooting space and the space available for the crown to develop. Is it a small bed next to a structure? Is it an area where a tree will have unlimited space to grow? Or is it somewhere in between?
Next, if you have a list of candidate trees, find out how large they will grow. Small trees look very innocent. Don't be fooled.
Check the labels on trees at a nursery. The heights listed are ranges only, not promises that trees will stop growing at the height listed. Try to find a knowledgeable employee and seek his or her input. Check more than one source as information may vary.
In determining what to plant, ask yourself what you hope to see there in the future. Do you want flowers, fall color, bright fruit, no fruit, interesting bark, a certain texture in the leaves, a short wide tree or narrow and tall?
If you do not know what to plant, look at pictures to find some interesting selections. Then learn about their preferred growing environments and sizes they will reach. For example, does a selection prefer shade, partial shade or full sun?
The bottom line is to select a tree that is right for the allotted space when it is mature and will thrive in the growing environment where it will be planted.
Trees to Avoid
I asked some arborist friends for recommendations of trees to either avoid or recognize that they are likely to have some serious problems.
John Hushagen, owner of Seattle tree Preservation Company, warned against planting Eucalyptus because it grows very fast and will die during a night of single digit temperatures. He also urged homeowners not to plant a giant sequoia or coastal redwood because few urban gardens can handle a mature specimen.
He also warned against planting Leyland cypress trees as a hedge because people usually "rue the day" they made such a choice. These trees should be planted where they can grow as large as possible and will never require topping or pruning.
His final warning was not to use many of the flowering cherry cultivars as street trees or near landscapes. They often develop very large surface roots and will destroy sidewalks, patios and driveways within just a few years. They are also very susceptible to brown rot fungi.
Bryce Landrud, owner of Thundering Oak Enterprises in Federal Way, offered two candidates to avoid. The first is Blieriana plum, a commonly planted purple leaf flowering ornamental, because of its "unruly" growth habit and susceptibility to numerous leaf and twig diseases and insects.
He is no fan of corkscrew willows because of their susceptibility to a leaf blight that often causes interior leaves and twigs to die.
Jim Barborinas, owner of Urban Forestry Services in Mount Vernon, suggests you avoid poplars unless you have a very large area that is seasonally wet.
Rather than avoiding a particular species, he reminds you to consider more of the smaller maturing varieties so that they better fit into our typically limited landscape spaces.
He continually sees large maturing trees planted much too close to each other as well as close to buildings and sidewalks. Imagine what a tree will look like in 30 to 50 years so someone will not be forced to cut down a crowded specimen. There are numerous small trees on the market and more being developed every year.
My personal list contains most spruce species. They are susceptible to numerous insects and spider mites that either deform or defoliate many trees. Dwarf Alberta and Colorado blue spruce trees are particularly vulnerable.
Alpine, sub-alpine and Fraser fir trees should also be avoided because of the balsam woolly adelgid. It is only a matter of "when", not "if" this devastating insect will find, deform and or kill these trees.
If you already have any of these trees in your landscape, please do not run out and cut them all down. Just beware of the pests and problems noted above.
Some of the problems can be controlled with sprays or soil or trunk injections. However, if your trees experience repeated attacks, some may become real eyesores. These can be removed and replaced with a well behaved variety.
Good luck with your spring planting.