August 18th – The poor acorns are really hampered this year – the gall wasps really seem to have affected them. These seem very like knopper galls, which are caused by the wasp injecting a chemical encased egg into the acorn bud when it’s forming. The chemical causes the acorn to mutate, and inside, the wasp larvae hates and feeds.
There are now a good few healthy acorns, though, so perhaps it’s not as bad as I feared, but I do wonder why it just seems to be oaks that are tortured so.
May 29th – I don’t know why, but I find these oak galls a bit horrible. They are distorted leaf buds, into which a wasp injects it’s egg and a chemical which causes the tree to grown the gall instead of a leaf stalk. The larva lives within the growth, feasting on it. When mature, the wasp eats it’s way out and the life cycle continues.
This tree on Clayhanger Common is peppered with these tumour-like galls – they look like fruit. The gall doesn’t harm the tree particularly, but it’s a very visible parasite.
there are many different types of gall wasp, all with different methods and growths. I’ve not seen this one before, and am unsure what it is specifically.
Nature can be very odd sometimes.
August 19th – The oaks are faring better this year for acorns. Last year, the crop here by the canal at Clayhanger, and over on Brownhills Common, was ravaged by knopper galls, which turn the oak fruit into odd-shaped aberrations that are home to the larvae of a tiny wasp. Thankfully, I could only see a handful of such curiously distorted acorns on this tree, which had a healthy looking crop of normal fruit maturing nicely.
What the tree was suffering, though, is unknown but fascinating. Leaves had inverted, and the undersides were covered with an annular ring, clearly left by fungi or some insect or other. They look like tiny breakfast cereal pieces, but are obviously killing the foliage.
Do any passing arborialists know what they are, please?
July 29th – Oak Apples, or galls, are an interesting thing. Very visible right now, they are the gall of a type of wasp that lays it’s egg inside new oak leaf buds. A chemical reaction caused by a secreted fluid causes the gall to grow, and inside, the wasp larva feeds on it, eventually burrowing it’s way to the surface and flying away.
Isn’t nature amazing?
September 22nd – a bright, sunshine autumn day. A ride through Staffordshire. My goodness, it was nippy as evening fell. It’s been one hell of a bad year for the oaks. I’ve previously recorded the absolute plague of knopper galls around Brownhills, devastating the acorn crop, and I’ve hardly seen any unharmed ones at all. Out in Staffordshire the story was the same. The ones that aren’t victim to the tiny, drilling wasp are small and sickly, affected by the lousy summer.
I hope they (and we) have a better time next year. To me, oaks are the epitome of the English tree, and when they suffer, I feel we all do a little bit.
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