In the past couple of weeks the weather has fluctuated from mild, seasonal temperatures with about an inch of rain, then more recent cold, wet snap and back to summery feeling highs. Seasonable day time highs, during the sunny period, and consistently cool night time lows along with the accumulated rainfall overall have been adequate for plant growth. The slow pace of spring development has caused extended, overlapping bloom periods, azaleas and rhododendrons are particularly spectacular right now. Lawns have greened up and mowing season is in full swing. On average 213 growing degree days have been added so far this season, and the soil temperatures have reached an average of 61 degrees. Of course as the growing season continues so do the potential problems, diseases have developed or are presenting in new life cycle stages. Discussed below are several currently being reported as active, this is, by no means, a complete list so make sure to contact your arborist with any questions, concerns or treatment needs.
Plant diseases may have many life cycle stages and multiple hosts so they may present differently in the late spring or early summer as air and soil temperatures rise and days grow longer and sunnier. These complex life cycles, morphological stages and multiple hosts can make identification and treatment tricky. Discussed below are some diseases which currently active. Your arborist will be able to properly assess disease on your landscape and recommend treatments and/or preventative measures.