Over the last several months the earthworm activity has continued to increase to nuisance levels. The cause of the increased earthworm activity is simple related to the precipitation we have received over this past year. Many of you may have also seen, in your personal lives, an increase in earwigs, ants and other soil living organisms. These insects along with earthworms lives in the soil. When precipitation levels and frequencies increase, many of the pore spaces in the soil begin to fill with water, in turn the oxygen levels in the soil dramatically decrease. When oxygen levels decrease, these insects need to find it to survive, so they go to where the oxygen is, the surface. Earthworms are no different and is the reason our earthworm issue is so bad right now. This time of year, when the temperatures are cooler, the soil takes much longer to drain/dry out. These normally air filled pore spaces will hold water much longer than in the late spring, summer and early fall.
Now, can we solve this problem? Ultimately, we need the faucets to shut off, but frozen temperatures will fix our problem in the temporary. Castings are also much more visible now because the grass has pretty much stopped growing. So for the grass to mask this issue, we will have to wait till next spring. Many years ago, there was research completed on the affects of topdressing and worm castings. Initially it was found that topdressing areas of your golf course and building up 1 to 2 inches of sand would correct worm cast issues. Now, if you ask researchers or the USGA, their tunes have changed, especially in years like this. Topdressing areas will not significantly affect worm activities.
When we topdress our greens during aerficiation, we are applying only about 1/8 of an inch of sand. To apply this amount of sand over our greens requires about 44 tons of sand. It also takes approximately 8 weeks for all that sand to be moved below levels in the turf that will not affect our mowers. To topdress our fairways and tees to levels which MAY help the earthworm issue, would take 5 to 6 years and many many tons of sand. It is a practice that just isn't cost affective for something that isn't even guaranteed to work. We do topdress our tees at Hartefeld, but not enough to make a signification impact on worms. I have made plans to begin topdressing many of our approaches this winter utilizing the dirty bunker sand we have removed during our bunker renovation. Topdressing our approaches will provide us with a better cut and allow the approaches to receive a golf shot better.
Eradicating earthworms by use of chemicals is also illegal, nor do we want to eliminate our earthworms. There are a few fungicides we apply throughout the summer that irritate earthworms. When we apply these products, you will see a reduction in the activity for a few weeks, when the product is no longer in the plant, the worm activity resumes.
Our earthworm activity is also not isolated to Hartefeld. Several high-end private facilities are also dealing with the same earthworm issue, Kennet Square Golf Club, Cedarbrook Country Club, Chester Valley Country Club, Whitford Country Club. These are just a few specific clubs, there are many many out there dealing with this. As I stated above, we need the rain to stop for our earthworm issue to decrease back to a more tolerable level. We also want to keep in mind, we need the earthworms in our rhizosphere; they play an integral part in creating our healthy soil and turf. However, just like anything else, too much of any thing is never a good thing.
