For the benefit of those who have never grown chufas and would like to see how fast they grow, I will try to put up a picture about once a week. I took this one yesterday, July 20, which is 2 weeks after spraying them. You can see they have grown since the last picture, and it's also worth noticing that the tire tracks from the spraying are starting to disappear.

I think the plants are a little too thick in this field, but that's better than not being thick enough. Turkeys are already scratching some of them up, so there must be a few small tubers on them.