I'm a terrible blogger. I haven't posted anything since January, and there was plenty to write about. I just didn't get around to posting any of it. Well, today is different because there is a population explosion of insects on my coast live oak (Quercus agrifolia). From inside the house it looked like a wet spot on the lower trunk of the tree. When I went outside to take a closer look, I saw that it was a mass of tiny insects huddled in a fairly tight cluster. I took a number of pictures, trying to get as much magnification as possible because the insects are very tiny, only about 1-2 mm in length.
I sent the photos around to a couple of different insect experts for identification. The unanimous answer I got from them was that these are called Bark Lice (Order Psocoptera). However, they are not true lice, nor are they bees, despite the superficial resemblances. They are fairly common in and under trees. They are not harmful in any way and may be considered beneficial in the big picture. They eat molds, pollen, and various other kinds of organic matter, so they are part of the large and important group of decomposers who help keep the world from being buried in debris.
These nymphs will grow and go through several molts, eventually emerging as winged adults. For a picture of the adult, see http://naturecloseups.com/wp-content/uploads/2012/02/00075806.jpg. Until now, I was unaware that this group of insects even existed. Now I am delighted to have them living in my yard, and I hope they will become permanent residents. I believe this has occurred due to the combination of native plants and totals absence of pesticides. While a native plant garden can never be considered a truly complete ecosystem, the appearance of species like this brings a level of ecological complexity that is very gratifying.