Sunday 18 March 2012

Towards The Good Scout

As long as there have been trees and shrubs there have been insects and diseases that live on and in them that reduce their beauty and utility in our landscapes and gardens.

A former professor and colleague, still very much active in arboriculture, would repeatedly regale us with tales of the good old days when you could just spray everything with lead arsenate and DDT. (He did this with a great deal of humor) This pretty well killed everything and life appeared to be good. However the toxicity, both instantaneous and residual was dramatic, indiscriminate and long lasting. Thankfully we have continued to evolve the process of maintaining our trees and shrubs with less and less toxic treatments while relearning cultural methods that require no chemical inputs. Indiscriminate spraying can result in the destruction of beneficial predatory insects, pollinators leading to resistant super pests that are difficult to control.

The discovery of chemical insect and disease controls was heralded as a dramatic breakthrough in both agriculture and horticulture. And it was, however old, time consuming practices such as breeding plant resistance and using cultural methods to limit the damage of pests were largely abandoned and forgotten when this new wave of chemical methods were embraced. Amazingly this “New Wave Approach “occurred in the 80’s, the 1880’s! It didn’t take long for problems linked to residual toxicity, and residue to spill over markets and dinner tables of the country and the world. In 1891 the New York Board of Health seized shipments of grapes and threw them into the river because they had visible traces of “Bordeaux Mixture “a mixture of copper sulfate and lime. Good for the grape eaters, not so good for the Hudson river. A British Royal Commission recommended safe levels of arsenate in food crops in 1903 after a series of poisonings. The British also threatened a ban on imports of American apples in 1925 due to high levels of lead arsenate. The industry continued to develop and expand the use of chemicals.

The realization that we may be harming ourselves and the environments continued to simmer until April Carson’s landmark book “Silent Spring” was published in 1962. This landmark book leads to the development of the modern environmental movement the initial steps towards finding a safer more environmentally friendly approach were called Integrated Pest Management.

Integrated Pest Management seeks to combine cultural, physical, beneficial, and chemical controls into an integrated approach to insect and disease control. Moving beyond I.P.M. the scouted Plant Health Care program puts a trained specialist on site to carefully monitor the trees and shrubs in your garden and orchestrate the correct treatment regime when necessary. The goal is always to minimize the application of chemicals, when possible using nontoxic products or cultural methods to limit the impacts of pests to acceptable levels. All treatments are carefully recorded and reported to the property owner as well as kept on file for future reference. I will continue to discuss the details of this topic in my next article. Your I.S.A. Certified Arborist is up to date on the latest research and can plan and execute your scouted plant health care program with modern scientific techniques.

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