Black Layer

Black layer is a common problem in sand based putting greens. Black layer is the result when metal sulphide occurs in the rootzone. It occurs when H2S gas combines with minerals in the rootzone which then leads to the formation of the metal sulphide. These conditions will ultimately result in root decline to the point that the grass plant will eventually die. When oxygen levels decrease in the rootzone we then see an increase in black layer formation. 

Practices such as over irrigating and fertilizing can help to promote black layer. When the soil is saturated commonly and for extended periods of time we see oxygen levels lower which can then lead to the increase of black layer. Using soil profilers/soil probes to take samples out of the green to look at along with submitting soil samples to soil labs can all be tools used to identify the presence of black layer. The black layer will be a very visible contrast when looked at compared to the existing sand base found within the rootzone. The smell can also be a very good characteristic in identifying black layer as the rootzone will have a "swampy/rotten egg" smell which is very distinguishable. 

Black layer from a creeping bentgrass putting green

 in northern Michigan. Photo by William Berndt

When black layer forms within the rootzone the most effective way to get rid of it is through cultural practices. The most effective cultural method will be by removing material from the act of core aeration. If the black layer is severe enough multiple aeration events may be required. Topdressing the greens with a new, clean sand material is also very helpful when performed in conjunction with aeration. These practices aid in increasing oxygen levels within the soil while also removing the areas of high sulphur contamination. Excessive thatch also helps to promote black layer by acting like a sponge that holds water at the surface so the aeration and topdressing helps to remove and dilute the excessive thatch that may be present. 

When it comes to products that may be available to aid in repairing issues from black layer there are a few options available on the market. Products that aid in promoting beneficial bacteria/microbial activity can be helpful in increasing soil oxygen and they can also aid by feeding on thatch. The use of aggressive acid based products can also be helpful to combat the black layer within the rootzone. Penetrants and surfactants that help to move water away from the surface/upper rootzone and lower into the profile can also be helpful and increase surface oxygen levels.

While curing black layer is important when it becomes present in your golf greens it is even more important to understand why it formed in the first place. Most often it is due to the overuse/improper use of irrigation water which leads to oversaturation in the soil. If this is the case it is important to make some changes to your irrigation program/practices to ensure the plant is being provided with only the amount of moisture it requires. It is also important to perform soil testing if black layer is becoming a problem to determine if anything in your soil is also helping to contribute to the black layer. If soil tests do indicate any problems then some changes to your fertility/amendment program may be required. 

Turf Fuel has a product called D-Solve that can be very helpful in attacking the mineralization buildups within the rootzone from black layer. D-Solve is a proprietary blend of strong, yet safe acids that are designed to solubilize exchangeable calcium, dissolve bicarbonate layering and move sodium from the soil. 

The Kraken Plus can also be a helpful water management tool for managing black layer as it can effectively move water downward and away from the surface of the rootzone. The Kraken Plus is a premier soil surfactant that provides tournament quality playing conditions. Built with two advanced polymers, fortified with S4 solvent. It is an effective tool against localized dryspot. 

Turf Fuel is committed to developing products that are not like any other on the market and finding solutions to the problems that have been plaguing turf managers for years. They are committed to always improving the already great products they currently have. Turf Fuel has solutions available from the most simple aspects of nitrogen nutrition to the much more complicated solutions that you have been looking for such as stress management.