July 3, 2002
While this year's weather looks like a repeat from last year-- a long drawn out cold spring followed by an immediate jump into summer--courses under our supervision came through the winter looking very good. We are finally caught up from this spring's rush, and are prepared to serve your mid-season needs.
A couple of superintendents have started making their own compost teas for spreading on greens and fairways. Needless to say, they are very excited about their programs and what they are doing. For little or no money, and no additional labor, these superintendents are incorporating compostincorporating compost teas into their maintenance fertilizer program. We will report on their results, especially any reduction in their fungicide programs later this year.
We are hearing compliments from superintendents who took our advice to use yeast in their top dressing and aeration programs. They see a marked improvement in the healing of greens and a marked healthy color change when the yeast has been added. It's long been known that yeast helps build the microbe population at a plant's roots. A healthy microbial population helps control plant disease. The color change' or "bloom," is a result of the yeast feeding the microbes.
One word of caution: As noted, spreading yeast increases the microbial populations and activity in your soils. To keep those microbial populations up and working in your favor, I would encourage you to continue to apply the yeast every four to six weeks or so. You can starve the microbes by not feeding them enough. Should this happen, you may experience a retreat in the quality of your turf.
This brings up another point. I am currently investigating the idea of blending yeast into fertilizer. In discussions I have had with many of you, you preferred the idea of having the yeast blended with the fertilizer rather than having it blended in your top-dressing sand You said the fertilizer companies would have more precise blending methods compared to sand companies. You questioned the quality of the yeast when mixed with the sand, and noted you have no control over the weather and hence little ability to control the yeast from breaking down and becoming activated. Packaging the yeast in a fertilizer bag would solve that. We will keep you posted on the progress of the yeast/fertilizer mix project.
The last time we visited, I said I would explain the difference between the two types of black layers that occur in your soils. One is the type that hangs in or just below your thatch, and the other type runs deeper and occurs lower in your soil profile. Let's talk about the latter first.
Black layer in the lower portions of your greens root zones is a warning of sub-drainage problems, and will be indicated by elevated sulfate levels on your soils report. This is a signal that the water either cannot escape the green or is having a hard time doing so. The only way to treat this problem is to make sure that the drainage in your greens is working properly.
Sometimes drainage lines are cut inadvertently when the course is being constructed. If that is the case, or if a drainage plain wasn't installed, you may need to consider adding drainage to the greens. If you do have drainage in your greens and are experiencing problems with black layer, check the outlets in your greens. When operating properly, there needs to be a negative pressure in your greens so when the water is draining through the root-zone, it will be pulling air (oxygen) behind it. If you have a drain tile that is covered by water in a pond or low area, the water flowing through the greens needs to overcome the head pressure of the water sitting in the drain tile. If the drain tile is too deep, water perking through the green cannot overcome the head pressure of the water in the drain, and water that is trying to perk through the root zone will not be able to exit the green properly. Black layer may well result.
The other type of black layer is a water management problem. Since course construction, a thatch layer has developed. The result of a thatch layer is a decrease the infiltration rate of the water into the root zone. Many times water is applied until puddling is seen, then the cycle is shut off. The problem is that the water soaks into the thatch and because of the higher water retention of the thatch, it stays there creating an anaerobic condition. Because of the thatch layer, you are able to apply water faster than it can infiltrate into the root zone. Think of it in much the same way as a faucet drip. The thatch will hold back much of the water, then slowly release the excess water over a longer period of time. The water is never actually allowed to flow or escape and perc through the soil profile and allow air to enter in behind it. The water basically stays in that area and that area will turn anaerobic. To get around that, or not have that happen you need to apply enough water so that the soil beneath reaches field capacity. Sometimes the best way to do that is to run one head at a time. This will slow down the application rate and allow your water more time to infiltrate the root zone and reach field capacity.
There are other issues that can also exacerbate the problem. One is trying to water the surrounds around the greens without part circle heads. Ideally, greens should be watered every three to ten days. Surrounds often dry out more quickly, and so are watered almost every night. This means that the greens are overwatered, which can of course ruin them. So the question is, do you treat the surrounds by increasing the organic matter which will increase the water holding capacity of the soil, and also use wetting agents, or go the expense of putting in part circle heads? This is not easy to answer, but each case should be looked at individually.
If the black layer occurs at an isolated spot on the green, then it could be a misadjusted fairway head hitting the green, or it may come from syringing. With syringing, the water may be following the thatch layer to the lowest part on the green where the water will not properly drain, but simply create an anaerobic condition. I have long been opposed to syringing because of this. The water hangs up in the thatch, and your root zone never gets to field capacity. If your course is experiencing this type of black layer problem, you may wish to look again at your watering methods.
I am carrying the black acetate strips with me on my visits this summer. If you suspect that you are developing anaerobic conditions in your greens, then let's take a few minutes to check it out. The black acetate paper often will show indications of black layer before you see it appear. This simple test will give you a leg up on taking preventative action.
Please feel free to get in touch with me if you feel you need something. I will be out of the office and cellular range the week of July 9th to the 16th. If there is anything you need, please call either the office phone or the cell phone and leave a message. I will return your call as soon as possible.
Thank you for allowing us to help you take charge of your turf.