June 20, 2007
Samples with the following problems have been seen in the Clinic lately: Apple scab on crabapple and mountain ash
Erineum gall on viburnum
The increase in bagworm populations noticed on arborvitae, juniper, red cedar and other trees in southern and central Iowa over the past few years appears to be continuing. Large populations of "miniature" bagworms were reported this week from Iowa City. Miniature bagworms, of course, are early instar caterpillars and the small bags that they construct from silk and bits of plant needles. Bags collected were about one-half inch in length. By the end of the summer, fully-grown bags will by approximately 2 inches long.
Grapevines can be supported and trained to a variety of structures. In the home garden, structures range from the decorative arbor to the conventional trellis.
Construction of a grape trellis is similar to constructing a farm fence. The trellis must be substantial enough to carry the weight of the vines plus a heavy crop during high winds. Basically, the trellis consists of two or three wires, one above the other, stretched tightly and secured to firmly-set posts.