Letters.

Bt and butterflies

The toxicity of Bt corn ("New studies clarify monarch worries," SN: 12/18&25/99, p. 391) has little to do with Bt corn being transgenic and much to do with the Bt toxin being less benign than hoped for. Bt dust is poisonous to insects regardless of whether it's produced by transgenic plants, sprayed by airplanes, or distributed by hand.

Spraying to control corn borers is often ineffective. Corn borers can be controlled by adding pesticides to irrigation water, but this practice is tightly controlled for fear of dangerous runoff. It was because of these difficulties that Bt corn was developed: It allows farmers to control a pest that would otherwise destroy their crops (and their profits and our food) because older methods were frequently unable to stop infestation.

Dave Argentar Bear, Del.

The study described merely corroborates the work of many other scientists showing that out in the real world, corn pollen concentrations rarely reach lethal levels, even on the leaves of milkweed plants growing within actively pollinating corn fields. Yet the article describes this as "hints that monarchs in the wild may not face a serious threat."

Alex Avery Staunton, Va.

It occurs to me that in the Midwest corn belt, finding a strip of land capable of supporting milkweed that is more than 10 meters wide is an exception. Monarchs may not have a lot of feeding choices other than the narrow strips of land between township roads and the next field.

On another note, has anyone thought about what happens to the corn pollen if a heavy thunderstorm washes it off the fields and into streams? Are we putting the aquatic food chain in jeopardy along with the soil microbes? This is an invention that needs to stay on the shelf.

Mike Davis Wabasha, Minn.

Ready, aim ...

The study described in "Suicidal link for gun owners" (SN: 12/11/99, p. 381) is flawed because it failed to take into account the method used in the suicides. The study appears to have a predetermined conclusion, justified by making the figures fit. California's 15-day waiting period for handgun purchases, mentioned in passing in the article, was implemented to prevent impulse buying. No mention is made of how many other guns may have been owned at the time of purchase, and it appears it was not considered. One alternative conclusion easily drawn is that many of the suicides spent time planning and even went so far as to purchase a gun in advance of the event.

James Longley Plano, Texas 

The findings described in the article are highly questionable, in that the researcher identifies the owners of firearms as having a predisposition to suicide. By focusing on the object only, he exposes his biases with regard to certain objects. A proper analysis of suicide must encompass every aspect of it and not just the object involved. Further, with the sheer number of firearm owners throughout the United States, it would have become obvious long ago if there was a problem in that regard. That there is not indicates that a mole hill is being made into a mountain.

Edward J. Totty Everett, Wash

Heady stuff

I am grateful for your article "Heading for injury" (SN: 11/27/99, p. 348). I have been kicking (and heading) soccer balls now for almost 30 years. I would like to point out that not all soccer balls are of the same quality.

I am constantly amazed by the fact that the vast majority of soccer balls sold in stores and in use today are a hard plastic, or so-called synthetic leather. Unfortunately, many adults don't realize how hard (and even painful) it can be to head and kick those hard plastic balls. And kids don't know any better. The cheap, hard plastic balls prevail over real leather balls.

My soccer ball of choice is made of rubber. It is head kind and less expensive, though hard to find. One more quick tip to reduce heading injury: Make sure the ball is not overinflated.

Jaime Hunter Garland, Texas

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