If it seems as though pests and diseases in the Lexington and Louisville landscape have become more problematic, it is more than just anecdotal conjecture. Researchers have documented expanding habitat ranges and increases in both fecundity and generations per growing season. Many factors lie at the root of these changes including longer growing seasons, milder winters, increased precipitation and increased CO2 levels. Kentucky weather records go back to 1895 and the Bluegrass Region has been trending warmer and wetter for the past 50 years. In fact the Bluegrass Region is currently at the warmest average temperature and wettest average precipitation rate since records began in 1895. (For more information, see the Kentucky Climate Center at Western Kentucky University)
The pests that seem to be responding strongest to these changes include scales, bagworms, white grubs, and spider mites. Root diseases and foliar diseases also seem to thrive in our changing environment. While pesticide options exist for the pests, not all diseases can be controlled by chemicals. Verticillium Wilt, Bacterial Leaf Scorch and Black Root Rot are the more common pathogens without pesticide control options that have disfigured and killed a wide variety of plants. Apple Scab is an example of a common disease that is easily controlled, but must be treated before symptoms appear.
The good news is there are ways to protect your landscape. Reducing environmental stress, keeping plants healthy, using resistant cultivars, and sanitizing are the best ways to combat pests and diseases. Identifying and treating problems early is vital, and options do exist for extending the useful life of plants infected by diseases that cannot be controlled by chemicals. Bio-control helps build green infrastructure by reducing chemical usage and increasing biodiversity. Remember the old gardener’s mantras: Right plant in the right place; and healthy plants begin with healthy soil.
