BEsT MANAGEMENT PRACTICEs HANDbooK - Tahoe BMP

that no detectable concentration of any pesticide shall be allowed to enter anystream environment zone unless the agency finds that application of thepesticide is necessary to attain or maintain the environmental thresholdstandards.Pesticide use in the Basin has been discouraged by TRPA since the 1987Regional Plan, which states that alternatives to chemical application should beemployed where practical. The policy aims to prevent potential harm from theoutset rather than manage it after the fact.Before any pest control methods are employed, a basic tenet of integrated pestmanagement (IPM) is to ascertain that there is actually a pest, and it has beencorrectly identified, before using any management tool. Factors that createdthe pest problem should be assessed to develop solutions. Otherwise, pests arelikely to recur.IPM practices include physical/mechanical, cultural, biological, and chemicalmethods. The different methods are often used in conjunction. Methods aretailored to the specific pest and its biology. Environmentally sound pestmanagement tactics, including prevention – the most important - are preferredto a reliance on chemical applications alone.Physical/mechanical methods (i.e. manual weeding, chainsaws, etc.) are oftenused for smaller scale infestations or in combination with other methods.Cultural methods include changing human behavior (e.g. plant pest-resistantspecies) or management to create healthy systems that are resistant to pests andresilient after disturbance. For instance, forests should be managed for healthystands that are not overcrowded and susceptible to pests and diseases. Thisincludes promoting vegetation diversity by planting different species, ages, andspatial arrangements to minimize pest problems.Biological methods such as releasing natural predators to attack their hosts (i.e.the pest plant) have been successfully used for large-scale infestations incombination with other IPM methods. An emerging method is biopesticides,which are certain types of pesticides derived from natural materials such asanimals, plants, bacteria, and minerals that control pests by low- or non-toxicmechanisms (e.g. pheromones).Conventional chemical pesticides are generally synthetic materials that aredirectly applied to the pest. You must read and understand the pesticide labelbefore you use a pesticide. The label is a legal document and is enforceable bylaw. It describes steps that must be taken to minimize chemical movement andcontamination of surface and groundwater resources. Property owners shouldnot use pesticides in or near water, while some pesticides are specificallydesigned for aquatic use; many pesticides are toxic to fish and aquaticinvertebrates.TRPA BMP HandbookCHAPTER 5: Soil and Vegetation Management2012 Page 5-13