Then, in the summer of 1988, I wanted to do an internship here in the Santa Clara Valley, and the only one available was with a tree service. Although the men with whom I spent that summer conformed splendidly to the stereotype, they were among the most dedicated of horticultural professionals I have ever worked with and continue to work with. None of them were "hackers," which is to arborists what "mow, blow and go" gardeners are to landscape maintenance gardeners.

Dedicated arborists who have studied the most contemporary arboricultural procedures and spend their careers improving their techniques are more common than one would think. However, the arboricultural industries are, unfortunately, attractive to many who are not exactly career-oriented. There are many hackers in the industry who have acquired a pickup truck and a chainsaw and claim to be arborists.

Although less money may initially be spent for work performed by less qualified "arborists," the expense of repairing the damage or of removing unsalvageable trees is almost always greater than the cost of securing the services of qualified arborists. (Damage to trees may not be immediately evident but may evolve as victim trees respond to improper arboricultural procedures.)

Reputation is very important when selecting an arborist or tree service. The best have likely been in business for many years and have many satisfied clients who would recommend them and continue to procure their services. Blair Glenn of Saratoga Tree Service, for example, has been serving some of his clients since 1974, but that is somewhat unusual. It is usually best to consider recommendations from friends, neighbors and other horticultural professionals. (And many arborists can recommend other proficient colleagues who have not been in business long enough to have gained a reputation.)

Certification with the International Society of Arboriculture (as a certified arborist) is an indication that an arborist takes his or her career and industry seriously. To become certified, an arborist must demonstrate arboricultural knowledge and experience by passing the initial certification examination. Certification must then be maintained by periodic attendance at various functions of the International Society of Arboriculture, including lectures, workshops and seminars.

Hackers typically lack such commitment and are very often not specialized. For example, they may advertise that they do fences, decks, concrete, brickwork, irrigation and so on. I actually see this quite often. Unless the individual is very versatile and very talented, this should be an indication that he or she is not sufficiently proficient at arboriculture to be dedicated to it as a career. This is also demonstrated by advertisement of procedures that are not arboriculturally or horticulturally correct, such as "topping." This barbaric procedure has always been deplorable among real arborists.

Mature trees are the most prominent features of a landscape and a substantial investment within the corresponding property. Maintenance of trees is therefore something that should not be compromised or trusted to hackers. More information can be obtained at the International Society of Arboriculture's website at www.isa-arbor.com.

Tree of the Week: Dracaena palm

The dracaena palm, Cordyline australis, is not a palm at all and is actually related to yuccas and agaves. The evergreen foliage is about three feet long, 2¹/2 inches wide and resembles that of yucca but is more pliable and pendulous. Mature trees may be as tall as 20 feet. The cultivar "Atropurpurea" exhibits bronze foliage but does not grow as tall or as quickly. Long, branching clusters of white, quarter-inch flowers appear in late spring. Dracaena palms tolerate drought and inferior soil but prefer regular irrigation and well-drained soil.

Horticulturist Tony Tomeo can be contacted at 408-358-2574 or at LGHORTICULTURE@aol.com.