localized dry spot

Tribute to golf course dogs:

I am going to start this week by stating that golf course dogs are some of the best dogs around. I met another one yesterday who was the sweetest thing, a black lab. I think dogs love riding in golf course utility carts even more than they like riding around in pickup trucks. I'm not the only one smitten. I met a superintendent once where the dog was "technically, an employee of the parks department" for chasing geese. I think he was pretty taken with her, because he said that if he changed jobs, the dog might mysteriously disappear with him.

Okay, onto more serious matters.

Localized dry spot:

I had a putting green sample come in the other day where the turf was wilty. There were 4 cup-cutter plugs. When I picked up the first one, I noticed that the sand felt absolutely powder-dry on my fingers. This can indicate hydrophobic soil (water-repellent soil), otherwise called localized dry spot (LDS).

I did the old trick of placing some water drops on the soil and seeing if they wicked in. They did NOT wick in—they just sat there. As I read online somewhere, putting water droplets on normal soil is like putting it on normal paper—the drops get wicked in. Putting droplets on hydrophobic soil is like putting them on wax paper—the drops just sit there beaded up.

I examined the other 3 plugs. One was fine—the sand felt wet, and the water drops wicked in fast. With the other two plugs, parts of the profile were okay, but parts were hydrophobic. Hydrophobic conditions are usually in the top one inch of the soil, but it can be variable. In one plug, the top 1-inch was fine and the lower 1-2 inch was hydrophobic. One of the photos below shows drops beading up in the 1-2 inch range, whereas drops applied to the upper 1-inch wicked in.

LDS has been associated with the decomposition of organic matter, where the sand becomes coated with hydrophobic molecules. This been associated with fungal growth—some fungi produce and secrete hydrophobic chemicals. In particular, fairy ring fungi can produce hydrophobic chemicals, leading to the most damaging types of necrotic rings, but LDS is not always associated with fairy rings. This particular green did have some fairy ring issues, but NOT in the sites where the plugs were taken. There could be a correlation, but it is hard to say.

Wetting agents can help to move water into hydrophobic areas and to evenly distribute the moisture. Be careful, though, as some products can cause phytotoxicity under some conditions. Read the label carefully.

Water droplets wicked in on top, but not in the 1-2 inch range

3 drops sit there, not wicking in:

Snow mold:

I was glad to see Jim's postings about snow mold. As a Wisconsin native, I'm familiar with the regions where he's doing his work. In fact, while visiting my parents in March (they live in Madison, WI, not too far from the turf research center and the University Ridge course where Jim does some work) I stumbled across some snow mold. See, there's a hiking trail that runs through the woods at U Ridge and connects with a regional trail called the Ice Age trail. My parents and I were having a lovely walk, then I got distracted by the snow mold and couldn't help but stop, hunt for sclerotia, then teach my mom and dad to hunt for sclerotia.

Then, we came out of the woods and I found some guys spraying. I strolled over and said, "So, what are you guys spraying?" I could see the look of skepticism in his eyes, and you can imagine his point of view. It's a little unusual to have a woman you've never met come walking out of the woods in March in Wisconsin and ask what you are spraying. So, I quickly followed with, "I'm a turf pathologist, and I know Jim Kerns." With introductions taken care of, I had a nice converation with the superintendent, Aron Hogden (Hi Aron, if you are reading this!)