Sometimes, when I send a photo to go with my column (for the SF Chronicle, at www.sfgate.com), there isn't room for it. I guess I had too much to say. So when that is the case, I will try to put those photos on my blog.
Today's photo is of bur clover, a weed that is related to other clovers and to peas and beans. The bur is a little pod, like a bean pod, that is curled up and has prongs along the edge to catch on fur or clothing. I've picked them up on cloth shoelaces. The plant has tiny yellow pea-type flowers and, like beans or white clover, each leaf has three leaflets. At the base of each leaf there are a pair of little wing-like structures called stipules. (If you see this plant, get out a hand lens and check out some of these details. They are really interesting when seen larger.) The plant lies fairly flat to the ground, so mowing often doesn't do much to control it. In fact, if you have it in a thinly covered grassy area, and mow the area, you will favor it over the grasses. If the grasses were to remain unmowed and grow over its top, the bur clover would be shaded out.
The writer whose question I answered in the column today had been told to pull bur clover out. This can work if you keep at it, since it is an annual plant, growing only from seeds. Pulling when the plant is small or when soil is moist or both works best. It seems to sprout at different times of year. I have the mature plants in the photograph in the garden now, but I see it in summer as well, from seeds that germinated in the spring.
The solution I gave in today's column was for a property that was not going to be actively gardened. Judith Lowry, of Larner Seeds (www.larnerseeds.com) suggested a cardboard mulch covered with purchased soil. In the purchased soil, she suggested sowing seeds of red fescue. This is a solution intended for California, near the coast, where red fescue is native. I'm sure there would be other best choices of grass for other parts of the world.