Ta-daa. Back again, and the part was only about $2.50, so not bad at all. The sprinkler heads come in 1/4, 1/2 and full circle patterns, this one being a half circle.
I dug down around the old sprinkler head and unscrewed it, revealing the top of the underground tube. I screwed the new one in place, replaced all the mud and dirt round the sprinkler, and then it was time to test it.
Ta-Daa again. No problem. I was really expecting this to be a much trickier job, or at least more expensive, but in fact it took about ten minutes and $2.50, so I had time for a cycle ride.
Early October, and at last the leaves are starting to fall. The Willamette Valley is a very lush and fertile area, and we are blessed with a lot of trees. This also means a lot of leaves come Fall, and the first leaves are falling. This seems a little late compared to London, but I think the seasons here have been running late generally, possibly due to Global Warming.