A bit of garden clearance in the rain is always therapeutic. Working off a good lunch and feeling the drip of water down my neck, I feel my endeavours are all the more noble.
A bit of garden clearance in the rain is always therapeutic. Working off a good lunch and feeling the drip of water down my neck, I feel my endeavours are all the more noble. Actually all I'm doing is ripping the vine out of the apple tree it's been trying to smother for the last two years. Like the vine mentioned in Adam's blog, it's a Vitis coignetiae, or crimson glory vine. The cultivar in our garden is 'Claret Cloak', and beautiful though it is, it's gone too far and needs cutting back. The tree isn't very old, it's not more than 20cm in diameter at the base, but the bark is rough and gnarled enough to provide the odd nook and cranny for overwintering ladybirds.
Surprisingly, these are not the recent alien invader Harmonia axyridis, the harlequin ladybird, although they were common enough in the garden during last summer. These are the orange ladybird, Halyzia sedecimguttata.
The first time I found this pretty beetle, in a West Sussex woodland, about 30 years ago, I was quite excited. It was then regarded as quite a scarce species, associated with ancient broadleaved woodlands, and especially with old beech trees. But in the last quarter century it has changed its status dramatically. The attachment to beech trees was supposedly because it fed on mildew on the leaves, it being one of the several mould-feeding ladybirds rather than the aphid-eating species. Nowadays it is most usually found on sycamore and lime trees and is much more abundant than ever before, especially in urban areas.
It has a habit of clustering together in small knots over the winter; the photograph here shows four I found snuggling down on a carved stone angel in Nunhead Cemetery a few years ago. The early arrivers give off a 'safety' pheromone (chemical scent) which attracts others to gather around them. The idea is that their warning colours are emphasized by the increasing numbers. The scent lingers throughout the summer so the same crevices are used year on year by subsequent generations. Very clever.
Another ladybird that is regularly found overwintering in gardens is the 16-spot, Tytthaspis sedimpunctata, another mildew feeder. A couple of years ago these were very common clustered at the bottom of the featheredge fence slats, but this year there don't seem to be any. I'm wondering whether this species has a safety pheromone or not. My pictures show them settled on dead leaves and stems. These are unlikely to be around for another year, so maybe this species finds new hibernation sites from scratch each year.
