Spring Gall week 2023 comes a week or so too early for central England. This year Spring has come slowly, and in fits and starts, with the result that leaf bud burst is only just underway for most trees.

Usually the first new galls of Spring are eriophyid galls on newly unfurled leaves, with Acer, Salix and Crataegus often galling as tge leaves open (I believe the mites overwinter within the bud scales, so can move in immediately). Cecid gall causers tend to be a bit later: early ones are Semudobia sp. Ovipositing into female Betula catkins, and Dasineura tiliae, but neither host is ready yet. Oak Apples should be forming now, but I have only one location close by where I've seen them. Other cynpids on Quercus must await the catkins.

All of this means my initial hunt relied on old galls, a few rusts, and some eriophyid big buds, leaving only about 3 currently tenanted galls out my first day's haul of 17 galls:

• Trioza centranthi. Until 6 years ago this psyllid could not over-winter inland in Britain. A colony was discoveted in Leicestershire in October 2016. I then found it in two locations in Nottinghamshire in early 2019, and discovered one more on checking photos taken even earlier (1st January). Four years down the line the galls are ubiquitous locally, and appear rapidly on new seedlingss.
• Box Leaf Miner: a winter cecid gall on Box. I'm lucky enough to have a local colony, which seems to have survived thebarrival of the Box Moth which has defoliated much of the plant. This is quite diffivult to find, mainly because Box tends to be regularly pruned and the galls/mines are found only in the latest leaves towards the end of a stem. The best bet is to locate Box which has been allowed to grow out: when I was telling Jenny Seawright what to look for she knew such a p.ant close to her, and had photos of the gall the nect day.
• Aceria cephalonea. This required close examination of newly opened Sycamore leaves, the bumps although reddened are stil small, and anthocyanin pigments mask the color difference.

In terms of likely suspects for the remainder of the week, I only have a handful of obvious targets: Marble Gall, two Semufobia, Hollyhock Rust. If leaf burst continues I might find Aceria macrochela, A. myriadum., and Phyllocoptes goniothorax (for some reason both the latter two are quite scarce close to me). A couple of fungal galls are also possible : a smut on Winter Aconite leaves, and both a smut and a rust on Lesser Celandine. The gall I've failed to find this year, which for some reason is a late Winter one locally, is Dasineura violae. All-in-all I don't expect to get to 30 galls in the week. For comparison in early May 2014 I led a gall walk at Attenbourough NR where we found 50 galls in a couple of hours (more eyes does make a big difference).

@sk53 here.

I wrote a journal post about my first day looking for galls around Nottingham, my home in the East Midlands of England. One of this project's originators, @merav, gave me permission to post the journal here.

I'm going to try posting each day's gall hunting as a comment to this journal.

Day 1

Spring Gall week 2023 comes a week or so too early for central England. This year Spring has come slowly, and in fits and starts, with the result that leaf bud burst is only just underway for most trees.

Usually the first new galls of Spring are eriophyid galls on newly unfurled leaves, with Acer, Salix and Crataegus often galling as tge leaves open (I believe the mites overwinter within the bud scales, so can move in immediately). Cecid gall causers tend to be a bit later: early ones are Semudobia sp. Ovipositing into female Betula catkins, and Dasineura tiliae, but neither host is ready yet. Oak Apples should be forming now, but I have only one location close by where I've seen them. Other cynpids on Quercus must await the catkins.

All of this means my initial hunt relied on old galls, a few rusts, and some eriophyid big buds, leaving only about 3 currently tenanted galls out my first day's haul of 17 galls:

• Trioza centranthi. Until 6 years ago this psyllid could not over-winter inland in Britain. A colony was discovered in Leicestershire by Graham Calow in October 2016. I then found it in two locations in Nottinghamshire in early 2019, and discovered one more on checking photos taken even earlier (1st January). Four years down the line the galls are ubiquitous locally, and appear rapidly on new seedlings.
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Box Leaf Miner : a winter cecid gall on Box. I'm lucky enough to have a local colony, which seems to have survived the arrival of the Box Moth which has defoliated much of the plant. This is quite difficult to find, mainly because Box tends to be regularly pruned and the galls/mines are found only in the latest leaves towards the end of a stem. The best bet is to locate Box which has been allowed to grow out: when I was telling Jenny Seawright what to look for she knew such a p.ant close to her, and had photos of the gall the next day.

Chaange of plan. I've decided to do subsequent days as separate posts: markup doesn't work as well in comments & ir makes it easier for other commenters. So this is day 3 of the 2023 Spring Gall Week.

I started the day with one objective: find the elusive Marble Gall. I remember seeing this and several other Oak galls in the opposite direction to my usual walks. I therefore earmarked it for the afternoon.

The morning proved serendipitous. Firstly, I stopped by some planted sapling birches, to check the new catkins. These are low enough to allow observation at eye level, unlike the ones at the end of the road which have been pruned. I've been checking out the development of the female catkins for a couple of weeks now. As they mature they turn upright, and the flowers open from the proximal (lower end). It's just possible to see two stigmas protroding very slightly. Once all flowers are open I expect to find female Semudobia ovipositing into the catkin, and that's exactly what I found today. I even made a little video, but cant share it on iNaturalist. These images aren't perfect as it was a bit breezy.

Here's a similar photo I took 11 years ago:

My second bit of serendipity was that I forgot to make bread this morning, so had to get some shop bread for lunch. I diverted en route to the shop to a large Bay Laurel covered with old galls of Lauritrioza alacris.

I followed my plan in the afternoon. Still a lot of trees with buds firmly closed. I found the three oaks on the lawns of tge main University campus, but drew a blank on the first. The second had a patch of twig covered by Lachnus aphids, and some Ramshorn galls. The third had a solitary Marble Gall. Success!

I carried on to look at a few Turkey Oaks, most were still in bud, another has hsd the gall-bearing branvhes pruned away, but was coming into leaf. Even the Lucombe Oak hybrid had lost all its leaves, so no chance of old galls there.

On the way back I looked at some Black Poplars by the ring road. A few old Spiral galls were visible, but no sign of leaves.

I finally broke the Marble Gall bogey, and added two more which I didn't expect.

I likely won't find anything on Day 4, as I have to stay at the house in the afternoon, but I plan a visit to the last of our local churchyards looking for the Artichoke gall on Yew. I'm hopeful about finding a few more mite galls by the end of the week, so 30 galls still looks in reach.