Left: Boxwood blight leaf symptoms on boxwood This photo is from the Connecticut Agricultural Experiment Station and is a contribution courtesy of S.M. Douglas, M.K. Inman, V.L. Smith, or P. Trenchard Right: Potted boxwood infected


with boxwood blight Kate Aitkenhead, USDA APHIS-PPQ


Remove and dispose of infected plants (including roots) immediately.


Do not compost the infected plant material. A wide range of commercial fungicides can offer short-term protection, (check Rutgers recommendations) however these need to be reapplied regularly throughout the season, and products available to homeowners provide little control. Avoid overhead irrigation (especially night-time irrigation) and any conditions that result in long periods of leaf wetness. Plant growers in New Jersey have applied fungicides to protect the plants from downy mildew throughout their production cycle, but that protection only lasts a few weeks after the plants leave the greenhouse or garden center. Here is a website with useful information from NH including some fact sheets: http://extension.unh.edu/Agric/AGGHFL/ DownyMildewonImpatiens.htm


Boxwood Blight


Boxwood blight (Cylindrocladium buxicola syn. C. psuedonaviculatum) is a fast acting fungus which affects most species of boxwood including Buxus sempervirens, B. microphylla var. japonica, and B. sinica var. insulari, as well as Pachysandra. Tis disease was first found in the United States in 2011 in Connecticut, North Carolina, and Virginia where it has caused significant damage to plants at specific growing facilities as well as in landscape settings. Symptoms of the disease to watch for begin as small brown spots on the leaves with dark borders which rapidly grow, coalesce, and turn whole leaves brown or straw colored, and usually cause them to drop. Plants will often try to flush out new growth which becomes infected again, causing the plant to weaken and potential die. Dark stem lesions are also characteristic, and can be found anywhere from the soil line to the tips of the plant. Boxwood blight is a serious disease for many reasons. It can complete its disease cycle in one week under warm and humid or wet conditions. It can easily be spread as it has sticky spores that disperse via wind, water, or on people’s tools, clothing or shoes when moving between


GrowingMEGreen


plants. Also fungicides have not been found to be very effective, but have been used in combination with strict sanitation measures to help suppress but not effectively remove the disease. While boxwood is not the most popular plant for Maine landscapes as it is not hardy in some areas, one must consider the disappointment this disease could present for your few customers who maintain formal gardens with boxwood hedges. Also, the other host pachysandra is more widely grown throughout the state. C. buxicola is therefore an important disease to keep in mind when speaking with your suppliers and finalizing your plant orders.


A New State Department Te new Maine Department of Agriculture, Conservation and


Forestry became official last week. Te new department, which merges the departments of Agriculture and Conservation, is the result of legislation signed into law earlier this year by the Governor. Tis department will have 732 full-time and seasonal employees and have a budget of $96.5 million. It will be organized into seven divisions:


• Division of Agricultural Resource Development; • Division of Forestry; • Division of Parks and Public Lands; • Division of Quality Assurance and Regulations; • Division of Animal and Plant Health; • Division of Geology and Natural Areas; and • Division of Land Use Planning, Permitting and Compliance. Te Horticulture program will continue to be a part of the


Division of Animal and Plant Health. You may wonder how this will impact your business? Te answer is that it will probably not have any impact on your interactions with the new department. We all have the same offices, email addresses and phone numbers.


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