TREES, PLEASE: Arboreal Caveat Emptor


By Tim Clancy.

Pot-Bellied Pig Syndrome

'Right tree, right place,' is an often-repeated mantra when it comes to choosing and siting trees in the landscape. Usually, this has to do with what I refer to as pot-bellied pig syndrome. Those adorable pets were all the rage when I first moved to San Diego in the late 1980s. How cold you resist a cute little intelligent animal that would both entertain you and provide companionship. Little did many people realize that these cute little animals were perhaps misrepresented by unscrupulous business people and in a few short months, the tiny pig had grown into a giant couch potato eating people out of house and home.

As with selecting the family pet, pig or otherwise, choosing trees should include careful planning for the future growth of the tree and finding a place that will accommodate that growth. Remember that trees will try to fill as much space as possible. That's their mission, so to speak. Along with top growth comes root growth, so we need to be aware of that as well.


Three Palms: Right Tree, Right Place?

Let's consider another right tree, right place scenario. This one has to do with three types of palm trees. The first two are the California fan palm (Washingtonia filifera), its hybrid the W. filibusta (W. filifera x W. robusta), and the fishtail palm (Caryota urens).

In the case of the of the Washingtonia palms, they should not be used anywhere there is a coastal influence. This is because they are susceptible to a malady named diamond scale. The name sounds like an insect pest but it is in fact a fungal disease. The disease causes diamond-shaped lesions on the host foliage. There is no chemical treatment available. In the case of the hybrid, the amount of disease present will depend on the amount each parent contributes to the hybrid as the Mexican fan palm (W. robusta) is not susceptible to the disease. So if there is more California fan palm, the disease can be severe than if there is more Mexican fan palm. Either way, it is best not to use a Washingtonia in areas of coastal influence as it won't be aesthetically pleasing in the long run.


In the case of the fishtail palm the issue to look out for is not a disease or pest problem, but a genetic one. The fishtail palm is monocarpic. This refers to a plant that flowers, sets seeds, and dies. In our climate, a fishtail palm generally grows for twenty years, flowers each year for about ten years, then, 'bye-bye!'—all the while looking progressively worse. For serious palm collectors, this is an acceptable scenario. However, imagine having paid for a specimen palm to be installed in your beautiful landscape (as a specimen, it may already be ten years old or more) and then it flowers and begins to decline. You may feel somewhat slighted, I imagine. Believe me—I have seen this, and the planting of the aforementioned fan palms in coastal zones happens on several occasions.

Right tree, right place indeed! Consider this a reminder of the implicit arboreal caveat emptor and take the time to ensure that the trees you choose are appropriate for the space and location of your property.

Editor's Note: Please see SelecTree's Right Tree, Right Place for additional things to consider when choosing trees for planting. Learn more about SelecTree in this newsletter issue at 'SelecTree: A Tree Selection Guide'.

*All images courtesy of the author.

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