PREVENTION OF  CHRONIC INSECT PROBLEMS OF  TREES & SHRUBS...

    The application of pesticides is normally discouraged unless absolutely necessary and then these applications are restricted to the target plant and its specific pest.  In other words, "blanket" spraying as a preventative throughout the entire garden to kill anything that crawls is a big "No No"!  Through the years we have become more concerned with our environment, resulting in the discontinued use of such heavy duty insecticides such as DDT, Chlordane, and most recently Dursban.  The makers of such compounds have focused their attention to newer compounds that are more specific to the target pest and have a less negative impact on the environment than the old "heavy hitters" mentioned above.  Some folks have zero tolerance for pesticides, while others condone the use of pesticides only when necessary.  Those who still nuke everything should reconsider your position.

    Having said all of this, I am going to talk about a very effective, newer product for the prevention of chronic insect infestations.  The common name of this product is Imidacloprid and it is marketed under the name of Merit or Bayer Advanced Garden Tree & Shrub Insect Control.
This product is systemic in action which means that it is absorbed into the vascular system of the plant yielding protection for an extended period of time.  This product will kill an insect on contact but its main strength is its systemic killing power on insects which choose to take a bite out of the treated plant - bad bug!  Non harmful insects which are just visiting but not foraging on the treated plant are less prone to harm by Merit.  This is a positive advance in the art of pest management.

    The spraying of this product gives a 2 to 3 week control, but the drenching of the roots in advance of the infestation gives up to 12 months of control.  Since some plants are plagued by a specific pest every year, the preventative soil drench application of Bayer Advanced Garden Tree & Shrub Insect Control is a great idea.  You may well know that your maple will shower your car with the sticky Woolly Maple Aphid, your Euonymus will struggle with eunoymus scale, your azaleas will lose needed chlorophyll to a massive assault of lace bugs, your boxwood leaves will blister from leaf miners, or your birch leaves will pucker and distort as a result of the birch aphid.

    Application of this product in advance of the growing season will control these problems, giving you a healthier plant and eliminating the need to introduce pesticides to the environment, the plant, and yourself repeatedly through the growing season.  Your success in control will be greater with a soil drench of Merit and only one application is needed.  I would recommend applying this product as a preventative measure for plants which invariably have heavy infestations of a particular pest.

    The cost of Bayer Advanced Garden Tree & Shrub Insect Control is about $20 to $25 per quart.  A tree should receive one ounce of product per inch of circumference.  Measure the diameter of the tree trunk at chest height and multiply by 3 to determine approximate circumference.  For trees with a circumference of less than 50 inches, mix the appropriate dosage with one gallon of water.  Use two gallons of water for trees with circumferences greater than 50 inches.  For multi-trunk trees, calculate the combined circumferences of all trunks and add them together to determine the numbers of ounces required.  For shrubs, measure the height of the plant and round up or down to the nearest foot.  Apply 3 ounces of product per foot of shrub height in one gallon of water.

    These drenches should be applied by pouring the diluted material from a bucket around the base of the plant as close to the main trunk as possible.  Following the drench, rinse the bucket by filling it with water and pouring the rinsate around the truck of the treated plant.  Application is best if made in the fall, but applications in spring dormancy are also good.  The material will protect the existing vegetation as well as new growth for as much as 12 months.  You should act now for the 2001 growing season.  A little work now will save a lot of work this summer.