The Wild Side of Beth Chatto Gardens: autumn plenty

I expected the final set of Wildside Walks for the year were going to focus upon nature preparing itself for the season to come. And yes, we looked at that although it all felt a bit superfluous as we were experiencing a short-lived, day-long heatwave, with temperatures around 26º Celsius, full sun and a light breeze, truly a (presumably) last blast of summer.

Chiffchaffs were in good song, a fleeting remembrance of spring, but soon quelled by the mournful, minor-key autumnal song of Robins, the twittering overflight of Swallows and the reedy wheezing of Siskins in the Alders. Down at the Reservoir, the Moorhen broods are growing fast, and the Mallards were joined by a pair of Gadwalls in the Duckweed soup…

Also around the ponds, there were still plenty of dragonflies and damselflies, with Common and Ruddy Darters, Migrant and Southern Hawkers, and most numerously Willow Emeralds, with lots of mating pairs fluttering about.

In the borders and beds, Rudbeckia, Verbena and Bistorta were pulling in the butterflies, especially Commas, Red Admirals and Peacocks, along with the ‘cabbage’ whites, and single Brimstone, Painted Lady, Small Heath and Common Blue. Sadly however, the Hummingbird Hawkmoth I had seen a few days previously was nowhere to be seen…

Bees and ladybirds were visiting the ice-plants in particular, always reliable at this time of year…

… and of course Ivy, the autumn pollen and nectar source par excellence. Hornets were everywhere, trawling noisily through insect-attracting flowers and leaping on anything too slow to get out of the way: the wasp in the photo below was despatched in seconds.

As the Sun’s intensity declines, so the importance of sun-basking increases so the insects can go about their business of feeding and breeding without becoming prey themselves. There were tachinid parasite-flies like Tachina fera, various other flies (just look at the covering of pollen!) and parasitic wasps, together with an array of true bugs: Cinnamon Bug, Dock Bug, Hairy and Green Shield-bugs. Plus a long-anticipated new species for the garden: Rhododendron Leafhoppers have been spreading since their arrival in Britain almost a century ago and are found on most local Rhododendron leaves, but not until now within our garden. Rhododendrophiles may hate them as they may help to spread diseases between host plants, but they are undeniably spectacular, while rhododendrons have very limited positive wildlife values. I love the bugs!

At this stage of autumn, our thoughts turn to Oak trees, especially in mast years like this with an abundance of large acorns.

The leaves are starting to look their age, many coated in mildew, nibbled or hosting the internal workings of leaf-mining insects, such as the sinuous galleries of the micromoth Stigmella ruficapitella (or similar).

And then there are the galls, distinctively shaped structures that signify the fact thattiny gall wasps are infecting the tree: Spangle Galls, Smooth Spangles, Oyster Galls, Knopper Galls, Cola Nut Galls and Ramshorn Galls are shown here, the latter also a new record for the garden.

There are of course many other types of gall-causers and leaf-miners, and plant species that exhibit them. The Holly Leaf-miner is a type of fly and the rough, raised galls on Alder leaves are caused by the mite Acalitus brevitarsus.

And searching leaves for galls and mines can also turn up other delights, such as the sputnik-shaped white egg-sacs of a small spider, Paidiscura pallens, again possibly the first time it has been recorded here. Indeed spiders and their webs are always a constant feature of autumn, none more impressive than the common Garden Cross Spider.

And so we come to the end of my Wildside Walks for the year. Thanks to all who joined them, or enjoyed reading about them. I hope they will return next spring: keep an eye on the events page of the Beth Chatto website Courses & Workshops – Beth Chatto’s Plants & Gardens or the page on my own website dedicated to the Beth Chatto Gardens Beth Chatto Gardens – activities and events | Chris Gibson Wildlife.