Bee Plague Threatens To Exterminate County Hive


Gardens Suffer The Effects Of Mite Infestation

April 07, 1991|By Mary Gold

The common honey bee is not on the endangered species list -- at least, not yet. But its numbers are dwindling dramatically here in Howard County and throughout the United States. Thomas Price, president ofthe Howard County Beekeepers Association, is worried. All of the bees in eight of his 10 hives died over the past winter, and those losses are mirrored throughout the county this year.

Tiny mites are theculprits. Two predatory mite species that have invaded the U.S. in the past few years use any member of the bee family as hosts, and theymean death to the bees they infest.

Beekeepers are bracing for bigger losses. In fact, the hobbyist beekeeper may soon be a thing of the past. In Howard County, the greatmajority of beekeepers fall into this category.

Honey lovers probably won't feel the effects of the bees' decline. The big losers besides the beekeepers in this ecological disaster are orchard owners, farmers and home gardeners.

Lessons of the "birds and bees" are no joke in this case. Pollination, or fertilization of plants, is key to much of our nation's food supply and to success in the backyard garden. Ninety percent of the world's plants depend on insects, mostly methodical bees, to produce fruit and seed -- for their own survival, aswell as for humans and other animals to consume.

As Price explained, bees accomplish thousands of dollars worth of pollinating for farmers and gardeners each year. In fact, last year's commercial cucumber crop on the Eastern Shore was severely affected by a lack of pollination. Beekeepers in the business of providing hives on a temporary basis to commercial growers couldn't keep up with demand, due to a lack of bees.

The varroa mite (varroa jacobsoni), which originated inAsia, affects young bees in particular by feeding on their blood. InEurope,this mite has completely wiped out the wild bee population, and only cultivated hives that are chemically treated survive. Price said the mites have been active in Howard County for approximately three years. Their appearance here has been traced to a ship that dockedin Baltimore's harbor.

The smaller and more mysterious tracheal mites (Acarapis woodi) were first noted in Europe more than 60 years ago. Dozens of these microscopic adult mites enter and feed within thebee's trachea. They are lethal to overwintering adult bees. Beekeepers detect little evidence of these mites until an entire hive fails to survive the winter. Their destruction of the bee industry in parts of England gave rise to the U.S. Federal Bee Disease Act of 1922, which bans the importation of live honey bees (except from Canada).

Bees, their diseases and parasites cross borders and oceans despite laws. And the spread of the mites within the United States has been accelerated by the migratory lifestyles that many commercial beekeepers maintain. If you have ever wondered how the same beekeeper can offer orange blossom honey and New England clover honey, envision a large truck loaded with hives following various flower crops up and down thecoast. What better way to spread the mites?

The Maryland Department of Agriculture maintains a regular health inspection program for both hobbyists and commercial beekeepers. Chemical pesticides that kill mites but leave bees unaffected are scarce. Some treatments used inthe hives controlthe mites somewhat but do not eliminate them, stresses Price. This complicates an already labor-intensive and money-losing avocation.

Home gardeners may well notice a drop in the productivity of certain crops this summer due to low pollination rates, saysDenise Sharp, regional specialist for vegetable production at the University of Maryland Cooperative Extension Home and Garden Information Center. Commercial growers are more conscious of pollination problems and work to maintain adequate bee populations. Home gardeners havetraditionally relied, perhaps unknowingly, on wild bee populations.

Particularly at risk are tree fruits like apples and pears, strawberries, blueberries and raspberries as well as all members of the cucurbit family -- cucumbers,melons and squashes.

To promote bee activity on their property, home gardeners should use great care with pesticides. Ill-timed applications of insecticides, in particular, can poison the good guys like bees along with garden pests, and are the bane of beekeepers.

If you do use chemical insecticides, fungicides and herbicides, choose those that break down quickly. Read the labelscarefully. Some of the most common over-the-counter insecticides, such as Cygon, Diazanon, Sevin, Malathion and Dursban, are very toxic to bees. And don't apply when plants -- be they vegetables, shrubs or groundcovers -- are in flower. Bees attracted to the blooms will not only infect themselves with residual poisons but may take them back to the hive. Information on applying pesticides properly with respect to bees may be obtained from the Home and Garden Information Center, at 1-800-342-2507.

Baltimore Sun Articles
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.