Earlier, we changed the Zone 1 irrigation to add bubblers for the crepe myrtle trees, described in the posting Changing the irrigation in the driveway peninsula. That left Zone 1 with 4 spray heads, as well as the 3 bubblers.
But the only things that are being "watered" by these heads are the two Barlett Pear trees, and maybe one crepe myrtle -- there used to be ferns and lamb's ear plants, but they have all disappeared. Either they were eaten by the deer or died from lack of water or sun.
And -- observing what happens when the sprinklers run -- only the top of the mulch gets wet; the water does not seem to get under the mulch to the dirt.
So we are replacing the three heads that are for the two Bartlett trees with bubblers. These will saturate the soil itself, under the mulch, and (hopefully) get water more directly to the trees roots.
This took half a day, but was relatively simple. I dug down to expose how the sprinkler riser was attached to the buried sprinkler lines.
Then we removed the long riser, replacing it with a shorter one that just comes up to ground level (or slightly less) and then put a bubbler on top of it.
Now when the sprinkler runs zone 1, there is no visible trace -- all the watering is being done by bubblers underground. At least we have little water wasted by misting and evaporation.
The fourth head (which really was not watering anything) was just capped off underground.
The main problem with this is going to be finding these bubblers if/when we need to do something with them. And then there is also the issue of whether it will be enough (or too much) water for the trees.