I received some exciting news just before Christmas – confirmation that I’d probably found on my local patch in King’s Lynn, a species new to Norfolk!
The newcomer is a gall caused by the mite Vasates quadripedes and was liberally dabbed on the leaves of a silver maple tree on the edge of the Reffley Estate’s Temple Wood when I discovered it earlier this year.
Indeed, the species is relatively new to Britain, having first been discovered in London in 2002.
I’d first spotted it during a walk round the Wood in early June. It looked like a lot of pink blobs on some of the leaves on the tree. Although I included a photograph of some affected leaves in a blog post around that time, no further information was forthcoming at that stage.
Later that same month, it was still very much in evidence, so I showed it to Norfolk naturalist, Nick Acheson, who gave a sample to the county fungi expert, Dr Tony Leech. The specimen was duly passed to the county gall expert, Anne Hickley, who identified it and reported that it was the first Norfolk record she was aware of!
Dr. Leech reported to me on Anne Hickley’s findings:
“The gall is caused by the mite Vasates quadripedes which occurs on both [silver and sugar maples]. It was first recorded in Britain (London) in 2002 but I don’t know how widespread it is although the NBN map (see link) suggests it is very little recorded (but possibly only a small number of records get to this database): https://data.nbn.org.uk/Taxa/NHMSYS0020190751/Grid_Map“
Wikipedia describes Vasates quadripedes as a maple bladder gall mite. It is part of the eriophyid mite family of plant parasites, which commonly cause galls or other damage to plant tissues. The mites are worm like and have only two pairs of legs, reports Wikipedia. Their main method of distribution is wind.
In America, the Vasates quadripedes mite causes galls on the leaves of silver maple (acer saccharinum), red maple (A. rubrum), and sugar maple (A. saccharum) and, in Britain, the mite affects introduced silver maples. The gall is rounded, or sometimes elongate, with a short thin neck. It is up to 5 millimetres high and may be very numerous on the upper surface of leaves. At first, continues Wikipedia, the galls are yellowish-green or bright red, later turning to dark red and black.
Although I first thought the host tree in Reffley Temple Wood was a sugar maple, I realise now it is a silver maple.It seems the gall mite can affect both trees. I have to say, it is easy to confuse the two trees, for their scientific names are very similar. Furthermore, whereas the sugar maple is now used in the USA for maple syrup, native Americans used to make sugar from the silver maple.