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A Cow's Nemesis

This summer has been tough in several ways. But one of the biggest issues has been with the cattle.

I'm going to say it. My cows have a fly problem.  It's embarrassing as a farmer, sort of like having your kids come home with lice from school, you really don't want the neighbors to know.

I have been struggling to control the horn and face flies organically since mid-June when, with all the heat and rain, the fly population skyrocketed.  The horn flies are the worst, because they are biting blood feeders that drive the cattle to distraction, causing them to walk continually looking for relief, cutting down on the time they spend eating.

I finally thought I got a handle it using neem extract and cooking oil which kills the horn flies on contact, if it gets on them. But then the face flies began to multiply.

Face flies don't bite, but feed on the secretions from the cows eyes, nose and mouth and can spread pink eye, a common cause of blindness in cattle. They are a general annoyance to the cows, especially in large numbers. Needless to say, I wasn't eager to let that happen, so I bought a fly trap that was recommended to me and added powdered garlic to the salt and mineral mix I give my cows.  

But at this point, the flies have had such a head start that I haven't been able to catch up.   And so, I have a fly problem.

The hardest part of the situation is that there is a simple solution: fly sprays that would end the fly population in a week, such is their toxicity.  A simple spray on the head of each cow and it's done, fly free for weeks at a time. Similarly, insecticidal ear tags in the cows' ears keep them fly free all summer, a simple and effective way to protect the cows.

When the vet came, he clearly thought I was crazy to not be deworming and treating my cows for flies.  He probably thought "Another damn idiot tree hugger," but at least he kept his own counsel. It's really hard to go against accepted practice and to head in another direction, but I do have my reasons.

First, my neighbor showed me the latest fly spray he bought - it cost him $700 for the 16 oz. spray bottle. That's a whole lot of gee whiz and almost the price of a 600 lb. calf at market. On top of that, the chemicals from the tags, sprays and pours get into the cows' blood stream, and is eventually excreted in their poop, where it carries on killing flies.  But the flies aren't the only thing being killed.  Iowa's pasture lands are almost entirely devoid of dung beetles, whose whole life purpose is to break up cow pies and haul them away for their babies. The dung beetles largely disrupt the life cycle of the flies because flies use intact cow pies as nurseries for their own eggs.  And so by killing off the dung beetles (and who knows how many other beneficial insects), we in fact enable the flies, who breed so quickly and voraciously that the chemicals my neighbor bought will become ineffective in just a few years.  

It just doesn't make sense to me to continue to feed the agro-chemical beast that preys upon farmers who don't have the time, knowledge or desire to build a balanced ecosystem where checks and balances come in months and years instead of days and weeks.   

But for now, my cows are miserable waiting for the damn dung beetles to show up, for the first frost to hit or for me to find a chemical free answer to the problem.

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Hi John, are these flies anything like fruit flies? When I have fruit flies in the kitchen, I make a simple funnel out of paper and put it in a glass with some cider vinegar at the bottom. The flies are attracted to the vinegar, go down the funnel, and can't get back out. I don't know if it would scale for your purposes, but it seems a lot like the trap you bought. I wish you the best of luck overcoming your challenges in the most purposeful way possible, if not the most expedient. Ken

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