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Nursery & Forest
Volume 57 Number 5 Date 05/10/2012 VOLUTELLA BLIGHT - This potentially lethal disease is reported to be infecting pachysandra at several nurseries in Ozaukee County. Volutella blight begins as small water-soaked lesions on the leaves that eventually turn brownish-black and necrotic. Recommended controls include removing diseased leaves, stems and debris, and thinning existing plantings to promote air flow. For severe cases, nursery operators should dig up or prune back infected plants and follow with one or more applications of a broad-spectrum fungicide (containing chlorothalonil) labeled for use on pachysandra. FROST INJURY - Nursery trees, shrubs and perennials are showing the effects of the frigid nights last month. The problem is evident statewide. Reports from the northwest and southeast regions indicate a wide variety of plants have been affected to some degree, including bleeding heart, hosta, hydrangea, magnolia, maple, spirea, weigela and yew. TOBACCO RATTLE VIRUS - Standard inspections in the past week found tobacco rattle virus (TRV) on bleeding hearts in Ozaukee, Racine, Walworth and Waukesha counties. This relatively new and increasingly common virus in the nursery trade can infect over 400 species of herbaceous and ornamental garden plants, vegetables and field crops. Symptoms include light and dark green mottling of the leaves, stunting, leaf distortion, crinkling or curling, streaking and chlorotic ringspots. Removal and destruction of symptomatic nursery stock is required as there are no effective chemical controls for this virus. --Liz Meils, DATCP Nursery Inspector GYPSY MOTH - Gypsy moth Btk treatments were applied from May 3-9 in Chippewa, Dunn, Eau Claire, Grant, Iowa, Jackson, Lafayette, Trempealeau and Vernon counties. Approximately 14,973 acres were treated. Spraying is scheduled to continue through the end of this week in Chippewa, Clark, Eau Claire, Jackson and Trempealeau counties, where sites will receive applications of Btk or Gypchek. Treatments have been completed for the season in Green, Grant, Iowa and Lafayette counties. --Nkauj Vang, DATCP Gypsy Moth Program 
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