May 9, 1997
Black Knot
Black knot is a fungal disease that occurs on wild and cultivated cherries and plums. Signs of the disease are easy to recognize. Black knots (or swellings) occur on branches, twigs, and/or the main trunk. These swellings, which are longer than wide, may extend up the branch from a few inches to a foot or more. They are especially noticeable before the leaves emerge in the spring.
Black Knot
Black knot is a fungal disease that occurs on wild and cultivated cherries and plums. Signs of the disease are easy to recognize. Black knots (or swellings) occur on branches, twigs, and/or the main trunk. These swellings, which are longer than wide, may extend up the branch from a few inches to a foot or more. They are especially noticeable before the leaves emerge in the spring.
Growing Hardy Geraniums
Hardy geraniums are easy to grow. Most species prefer moist, well-drained soils and partial shade to full sun. They have few insect or disease problems.
In spite of their favorable qualities, hardy geraniums are not widely planted in home gardens. Gardeners may want to try some of the following species and cultivars.
Infectious Needle Disease of Conifers
Infectious needle diseases of conifers, such as Dothistroma needle blight on Austrian pine, brown spot of Scots pine, and Rhizosphaera needle cast of spruce are controlled primarily through the use of protectant fungicide sprays in the springs. The first spray is typically applied around mid-May and a second application a month later.