Monday, 7 January 2013

the first field trip to the allotment in 2013

Field Study's Man in E17 found himself transporting a bottle of oxalic acid up to the allotment/apiary today. Oxalic acid is a very corrosive substance depending on the concentration. The bottle of oxalic acid I took was a 6% solution in sugar and distilled water, and it carried a warning sign similar to the one featured above. Why the need for this 'hazchem'? Oxalic acid is a substance used to treat colonies of honey bees for varroa mite infestation. The substance is so noxious in the confines of beehives it damages the mouthparts of the mites clinging to the adult honeybees and with damaged mouthparts the mites cannot feed and therefore die.
There is some debate about how oxalic 'works' and there are some additional and alternative theories about the acid treatment. Oxalic acid is supposed to be administered in December/early January because (in the UK) this is the time of year when the queen bee stops laying eggs due to the cold and lack of forage. With the honeybee colony in a form of hibernation there should be little or no brood in the hive (their nest). Varroa mites prefer to live on bee larvae (brood) protected and incubated within the wax honeycomb. Oxalic acid cannot penetrate the honeycomb however it will damage bee larvae in uncapped honeycomb. Oxalic acid is significantly less harmful to the adult honeybees although some practitioners of certain sorts of apiculture may argue differently.
I had some reservations about administering oxalic acid today. The weather has been so mild recently that it's likely queen bees have not stopped laying and therefore most hives/colonies will not be broodless. Even though the weather may have been mild enough not to discourage laying it is still cool enough (at 10 degrees e.g.) to adversely chill a colony if opening up the brood box and lifting the frames to check for brood. In addition to these concerns about oxalic acid treatment there is also one about nutrition and sustenance. There is little or no forage (nectar and pollen) at this time of year and so honeybees need to conserve honey stores and other nutrients in the combs and in their bodies as much as possible until the spring when plants start flowering and forage (nectar and pollen) becomes available. Winter brood may be counter-productive because it will use more of those stores.
While the weather has been mild and very wet through December into January it is quite possible there will be some very cold weather soon that will be to the detriment of  bee brood especially, let alone the potentially impoverished adult bee population.
The grim prognosis is malnourished diseased honeybee colonies less able to revive themselves in the spring and thus likely die off. I went ahead with the oxalic acid application anyway. I was told emphatically by the supplier that I should apply the acid in the concentration supplied in the bottle yet this evening I have read it is better to apply a 3.2% solution. There's not much I can do about it now if I have over dosed the bees.
A view of the apiary

Dead bees at the entrance of a hive - an occurrence usual at this time of year

Mold growing from/in one of the hive compartments probably due to the damp mild weather

Elsewhere on the allotment the garlic is beginning to grow and there is welcome evidence of worm activity in the raised beds.

and there was a well rotted pile of grass clippings and leaf mold replete with worms to salvage for the purposes of making a rich loam based compost which is very useful for dealing with the heavy clay soil on this site.

Field Study's Man in E17 did not lose himself entirely in the pleasures of the site for preying on his mind were various issues concerning Base Camp Beere closer to home in E17.

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