November 11, 1994
One of the enduring folk tales that relates to insects is that you can forecast the winter weather by examining the woollybear caterpillars in the fall. The woollybear in question is not just any of the 8 or more species of fuzzy, bristly-haired, tiger moth caterpillars found in the U.S., but rather the banded woollybear, the caterpillar stage of the isabella moth, Pyrrharctia isabella.
Nematodes are microscopic worms that are free-living or parasites of plants or animals. Most plant parasitic nematodes live in the soil and attack plant roots. Foliar nematodes, in contrast, feed on the aboveground parts of plants. Recently, a chrysanthemum infected with the foliar nematode, Aphelenchoides ritzemabosi, was submitted to the Plant Disease Clinic.
Many gardeners delight in producing a breath of spring during the cold winter months. The breath of spring I'm referring to is forcing spring-flowering bulbs. Bulbs can be purchased at garden centers, flower shops, or through mail-order suppliers in the fall. Select bulbs that are large, firm, blemish-free, and of uniform size. Forcing bulbs indoors requires forethought. Most bulbs require at least 12 to 16 weeks of cold treatment to initiate a well developed root system, stems, and flower buds.
The gypsy moth situation in Iowa in 1994 was another good-news-bad-news story.
Good news. The good news is that 10 very small infestations (1 to 10 acres each) discovered in 1992 and sprayed with Bt in 1993 had no caterpillar or moth captures in 1994. This adds to the Iowa Department of Agriculture and Land Stewardship string of successful eradications of the small, isolated infestations of gypsy moth that result from transport into the state on vehicles and nursery stock.
The poinsettia is a colorful symbol of the Christmas season. Poinsettias often appear in florist shops, greenhouses, and other retail outlets in late November. Careful selection and care should help insure an attractive poinsettia throughout the holiday season.
Most modern roses grown in Iowa require protection during winter months. Exposure to low temperatures and rapid temperature changes injure and often kill unprotected roses.
Hilling or mounding soil around the base of each plant is an excellent way to protect bush-type roses. Bush-type roses include hybrid teas, floribundas, and grandifloras.