Monday, August 31, 2009

The Nozzle Dance

Golfers that venture out on the course at the crack of dawn sometimes comment on wet conditions, soft spots, and mud on their balls. Obviously the superintendent has been over watering the course. If he/she would just turn down the water or shut off a couple of heads, the wet spots would disappear and the course would be firm, green, and uniform. I truly wish it was that simple.

I try to water as little as I can, just enough to keep the grass growing. I don't care if it is green, as long as the turf is playable and not wet, I'm happy. Well, I'm not happy, but I won't have to drink myself to sleep. I used to think it was as simple as turning down the water and letting things dry out. As the irrigation is tightened up, you'll begin to notice some areas dry much faster than others. Some, against everything that makes sense in this world, remain soft and on the damp side. Other spots absolutely roast and leave me wishing that I watered the night before because wet grass might be better than no grass.

So then you move on to fine tuning the system by adjusting the percentage of water each head (sprinkler) puts out on a nightly basis. Each head irrigates a slightly different microcosm with varying soils, slopes, grass species, wind, sun, and traffic. It takes a long while to dial things in and the adjustments always need to be made.

Then, if you still have a problem, perhaps the soil needs some work. Well, the soil here does need some work and we've been going at it with wetting agents, aerifiers, and subsurface drainage. These items helped, but the uniformity is still not what it should be.

So on to the Nozzle Dance. Our sprinkler heads are fairly advanced and they better be with a price tag of nearly $150. There are 3 nozzles in most of the heads: one large main, and two smaller back up nozzles. Some of the fairways have shown a uniformity issue, but I've been reluctant to start switching nozzles. I've gone down this road before and wound up returning the original nozzles after making a mess with every other arrangement. Hopefully, this time around will be different.

We recently installed some new secondary nozzles that seem to target the dry rings around our heads and to minimize the water that's delivered near the source. In the test plot we've had the wet areas around each head firm up without stressing out. The dry portions have greened up, but are still very firm. This is exactly what we are looking for, so the results have been positive.
Below are two photographs of a sprinkler head. The one on the left is spraying with the three original nozzles while the right is using the new configuration.

In both photos the main nozzle points to the right and the backups are spraying left. The new nozzles, in the photo to the right, are achieving a better spread and distributing the water evenly over the entire area. At least it looks that way now. That is why I call it a dance. Many times a new problem develops that will have you dancing around with a new configuration. The test plot has been monitored for over 3 weeks, so I think we can skip the dance and move straight to the after party. If this simple fix improves the fairways the way I think it will, we will all have something to celebrate.