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The Jelecote pine, also called Mexican yellow pine, is an uncommon evergreen whose distinguishing trait is its long, light green needles that hang vertically.
Photograph by Shari Kaplan
Pest, disease control can be environmentally safe
By Tony Tomeo
Those of us who truly enjoy gardening generally try to avoid problem situations that require the use of chemical pesticides. Application of pesticides is not the sort of chore garden enthusiasts enjoy. Most garden enthusiasts are also concerned about the environment beyond the garden and find the use of potentially toxic chemicals to be objectionable. Consequently, many less toxic methods have been developed to control pests and diseases.
The most obvious remedy for disease or pests is limiting the selection of species for the garden to those that are not susceptible to the most prominent diseases and pests. For example, snapdragons are very susceptible to rust and powdery mildew and should not be grown if either disease has been observed either among other species or snapdragons grown earlier.
The environments within the garden may be modified to gratify that which grows there, but should not be as conducive to disease and pest organisms. For example, roses that are often infected with rust and powdery mildew may experience serious problems in areas that are regularly moist and humid. However, roses grown where dry air is well-circulated and irrigation is applied to the soil (avoiding foliage) in early morning may perform very well without pesticides. Many disease infestations may be remedied by adjustment of irrigation.
Many insect infestations are more easily controlled with applications of simple alternative 'pesticides' that are harmless to the environment. Insecticidal soaps similar to dish soap very effectively control aphids. (Many garden enthusiasts prefer to use dish soap, but you didn't hear that from me.) A very dilute solution of soap--more diluted than what dishes should be washed in--explodes (or implodes, I can't remember which) the aphids as their bodily fluids react with the solution, which is of a very different pH. Scale (another pest) is easily suffocated by horticultural oil, which is no more detrimental to the environment than vegetable oil.
The West Valley Clean Water Program is very concerned with the reduction of pesticide use and in minimizing the quantity of toxins that flow into drains and ultimately into the San Francisco Bay. To promote the use of alternative pest control, the West Valley Clean Water Program has developed brochures describing environmentally respectful control procedures for pests that are commonly encountered in the garden as well as a few that may be encountered in the home. I have found these resources to be very informative, and I will likely feature more specific topics throughout the year.
Some of the brochures I recently received from the West Valley Clean Water Program are concerned with the control of ants, aphids, slugs and snails. Another brochure describes problem pesticides--those that are most toxic and harmful to the environment. Other issues include selection of appropriate roses, lawn care, safe use of pesticides and attracting beneficial predatory insects to the garden and maintaining their populations. Any of these brochures, or additional information, can be obtained by calling 408.354.5385 or 408.354.4734.
As I mentioned, I will try to feature much of this information as space allows, but I cannot discuss it all in just one week.
Tree of the Week: Jelecote pine
I studied this pine as Mexican yellow pine, and some people may know it by that name. The Jelecote pine, Pinus patula, is somewhat rare, but one of the more intriguing pines. Research reveals that this species is one of the fastest growing pines and may grow to 70 feet tall. However, the few that I have been acquainted with are rather small and slow-growing, likely as a result of the dense soil of the Santa Clara Valley. In fact, I know of a specific tree that is now maintained at about 20 feet tall and wide, but was about 10 feet tall in 1972 when I started kindergarten.
Well-structured trees are broadly pyramidal and not densely branched. The slender light green, needles may be as long as 10 inches and hang vertically, which is the tree's most striking characteristic. The foliar canopies provide only light shade. Chlorosis may occur if soil is too saturated. The Jelecote pine is not commonly available and may need to be ordered from specialty nurseries. Many garden enthusiasts encounter this species in older gardens that were developed when it was more popular.
Horticulturist Tony Tomeo can be contacted at 408.358.2574 or at LGHORTICULTURE@aol.com.
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Sunnyvale, California Since 1994
