Johnson Ops Tree Care Blog

Oak wilt is widespread in southern Wisconsin but in much of northern Wisconsin it is still a new and uncommon diseas Oak wilt kills thousands of trees each year in forests, woodlots and urban areas, or  can even attack and kill healthy trees. The disease is a particularly serious problem for species in the red oak group such as northern red, northern pin and black oaks. Once wilting symptoms are apparent on a red oak, the infected tree will lose most of its leaves and die within approximately one month. […]

MEET THE PEST The Japanese Beetle is coppery bronze and beautiful, but the mess it leaves behind, with its voracious appetite, it tears through foliage, flowers, and roots of more than 300 plant species. Both as adults and as grubs (the larval stage), Japanese beetles are destructive plant pests. Adults feed on the foliage and fruits of several hundred species of fruit trees, ornamental trees, shrubs, vines, and field and vegetable crops. Adults leave behind skeletonized leaves and large, irregular holes in leaves. PEST TYPE Chewing insect (Popillia japonica) ORIGIN & DISTRIBUTION […]

Bur Oak Blight Bur Oak Blight is a fungal disease that is relatively new to our area and that we should be aware of. The blight first appears in June as purple-brown spots on the underside of Bur Oak leaf veins. In July, the spots expand, and purplish necrotic veins become noticeable on the upper leaf surface. Leaf veins are killed as the infection progresses and a characteristic wedge-shaped necrotic area develops on the leaf blade. The trees have a scorched appearance with the disease typically worse on the bottom […]