Wednesday, January 16, 2008

How we manage pests and disease

We strongly believe there are too many unknowns to safely use toxins in our food production, and we’re hopelessly optimistic when it comes to finding local solutions. This week we want to tell you about the local solutions we employ.

Before dealing with the biggest problem, varroa mites, we want to touch on some others. Unlike varroa medications, the antibiotics that other beekeepers put in their hives generally aren’t used in response to any particular problem. In other words, antibiotics are typically used to treat diseases that aren’t even there. These problems are easy for us to deal with naturally. It’s incredibly simple and it takes us practically no extra time to inspect for the foulbrood diseases. As is the case with most smaller scale beekeepers, we have never had a case of foulbrood, and we certainly won’t put antibiotics in the hive for a problem that’s easy to diagnose and isn’t there. Other diseases like nosema are rare and mild enough that doing without the antibiotic for that disease is even easier yet.

The parasitic varroa mite, on the other hand, is not an easy problem to deal with naturally. Yet, by taking advantage of all the little things we can, breeding our own queens, and keeping the scale of our farm under control we have been able to deal with the mites very successfully. To help minimize the problem we keep close records on mite levels in each of the hives and use the most mite-resistant colonies for breeder stock. We also use special screened hive bottoms that let some of the mites fall out of the hive. Then, the most important thing we do to keep mite levels under control is called drone trapping. Varroa mites prefer drone brood (brood=the bees in the developmental stages) to worker brood, so we keep one frame of all drone brood in each of our hives. We keep a record of when each frame is added, and then remove the frame after the drone cells are sealed with wax (10 days) and before the drones hatch (24 days). We feed the drone pupae to the chickens, place the empty comb in the freezer to kill any remaining mites, and then repeat the cycle. By cycling drone brood through our hives like this we have managed to keep mite levels below the treatment threshold in all but two of our forty-eight hives. Another point to note is that we test each of our hives for mites this time of year. Without testing we wouldn’t know where to target our treatment and would probably be left having to treat everything, but with only two hives to treat we can easily forego the quick and easy chemical treatments. What we use on the hives with marginal problem levels is a spray synthesized from coconut oil and regular table sugar and diluted heavily with water. It’s chemically identical to a compound found naturally in the leaves of some plants. The spray, sold under the name of sucrocide, requires removing each frame one at a time and spraying the bees on each side, and then repeating two more times over the course of a brood cycle (21 days). Instead of poisoning the mites, the spray creates a soapy-oily film that simply suffocates the mites but leaves the relatively larger bees unharmed. In general, our disease and pest management methods take substantially more time, but they save us money on chemicals, benefit other parts of our farm (like the chickens), give us a better and more up-to-date knowledge of conditions in the hive and the field, and they yield a product we’re happy to eat and to sell.

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