Friday, 5 August 2016

Thorny issues

We learned as children in Sunday School how some of the Biblical farmer's seeds fell amid thorns, and thorny ground is what I am traversing today. I mentioned recently how tricky it is to distinguish between the September Thorn - famous for arriving in July - and the August Thorn which usually follows a little later. To compound the confusion, we also welcome at this time of year the Dusky Thorn which is what I think we have today.

Regular readers know that I am the last person who should pontificate on such matters, but luckily I do not need to as on the ever-excellent Upper Thames Moths blog,  Adam Bassett has contributed a really useful post on sorting out Thorns, which you can read here. You can then decide whether I'm right in my dusky diagnosis or not. Here are a whole lot more pictures - actually of two moths which were in the trap on the same morning last week (pre-rain, which I'm glad to say seems now to have gone away, as in the rhyme which Penny and I sing to the grandchildren).)

One interesting distinction between the lookalike Thorns is their differing diet. The August's caterpillars like Oak best, Septembers go for that too but also wander to Limes, Beeches and Birch, the Dusky sticks to Ash (though will accept Privet in captivity) and the Canary-shouldered likes Downy and Silver Birch.

If the last two aren't Dusky, then I give up.  Finally, here is a battered but completely flightworthy Swallow Prominent, just to stop this being an entirely thorny issue.

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