Twenty-five years ago, when I first began hiking up through the neighborhoods in the north Berkeley Hills (on my way to the intersection of Spruce and Grizzly Peak), I couldn't help noticing the grotesquely large hairy spiders sitting in the exact center of their huge, hap-hazard, beautiful, scintillating-in-the-sun spiderwebs. Some of these constructions seem to be built on the scale of a cathedral - I just saw one the other day stretching the height and breadth of a typical Berkeley Bungalow. Sometimes one sees them in diminishing fractals, a large one, followed two feet away by a smaller circle, and so on, down to the baby spider-sized web.
Over the years, I observed sightings of the numerous spiders and their webs steadily marching lower and lower down in the hills, and finally, just several years ago, I began to find them in my own neighborhood, and on my own street and in my yard. Now, when I step outside in the morning, I never know if I am going to walk right into one! They seem harmless enough, scurrying away as I brutishly tear through their delicate filigreed webs of silver. Some years the spiders are so very numerous that it seems as if the house and its surrounding plants have become positively mummified in spiderwebs! This may seem like an exagerration, but I have a friend who never leaves her home in late summer and early fall without a switch to twirl around in front of her face so she won't walk into one of the sticky webs, invisible except when touched by the sun.
Like a perpetually junior naturalist, I have observed them as they have expanded their territory. HOwever, this has not been much of a feat in the annals of science, as it turns out they are very well-known and even common, an invasive European spider called Cross Orb-Weavers (among other names like Garden Spider or Diadem Spider). I found this passage about them on Wikipedia, which includes photos (I've tried to photograph them, but my camera must not be up to the job, and I notice that the photos did not transfer from Wikipedia. Probably Something in the universe wants to spare you nightmares): "The European garden spider, diadem spider, or cross spider (Araneus diadematus) is a very common and well-known orb-weaver spider in Europe and parts of North America, in a range extending from New England and the Southeast to California and the northwestern United States and adjacent parts of southern Canada.
"Individual spiders' colouring can range from extremely light yellow to very dark grey, but all European garden spiders have mottled markings across the back with five or more large white dots forming a cross. The white dots result from cells that are filled with guanine, which is a byproduct of protein metabolism.
European Garden Spider in Coudersport, PA (photo available on Wikipedia)
Female in the UK with traces of Dew (ditto)
The third pair of legs of garden spiders are specialized for assisting in the spinning of orb webs. These spiders also use them to move around on their web without getting stuck. These legs are useful only in the web; while on the ground, these legs are of little value."
I can see why these spiders are called 'diadems.' They sit like a jewel in a setting in the very center of their web and have a jewel-like appearance, as long as you don't get too close, in which case they turn into remarkably ugly, hairy spiders! Eeek!
I am really surprised to discover that these Diadem spiders are so common. I've never seen them in my life before I moved to Berkeley. Or maybe I've just never seen such humungously large ones. Right now we are inundated by them. Who would ever guess that Berkeley, in late summer, is completely swaddled in spiderwebs?