Outside of disrupting the busy golf schedule and rearranging our usual spring mowing patterns, the recent rains have brought Mother Natures aerators, earthworms, to the surface. Fortunately or unfortunately, depending how you look at this, these guys are usually beneficial to the environment. They are a sign of healthy soil and create passages into the soil which allows water, air and nutrients to the root systems. In most circumstances they go unnoticed in home lawns, gardens and throughout most areas of the golf course. That is until we get into very wet weather like we did the week before last.
Their castings which are a by product of their digestive system have wreak havoc on low cut surfaces like fairways and tees! Their castings which have a heavy soil content create half dollar size spots in the fairways and tees that smother the grass when rolled over by carts and more so, mowing equipment.
The casting also create chaos with the mowing equipment as they can be drawn into the reels, dulling the blades and build up on the rollers which can alter the height of cut. They are as much as a challenge to your game as they are to us while we try to provide superior playing conditions.
The photo above shows the mud being smeared on turf causing dulling of the mowers and poor lies!
So what can we do about these animals? Our choices are very limited! There are no insecticides labeled in the U.S. to control them. There are studies that indicate topdressing fairways with angular sand encourages them to move to the roughs where the soil is less abrasive. This is a very expensive option! There is also an organic fertilizer that contains tea seed meal which has been shown to have some success when applied on the onset of a steady rain, irrigation is apparently not effective in washing in the fertilizer. The cost isn’t cheap either, about $400.00/acre the last time I checked(we currently treat 20 acres of fairways or $8000.00/treatment). Reading other Superintendent blogs, this product must be applied while they are active on the surface and must be watered in with at least 1/2″ of natural rain. It has no residual so supplementing irrigation after a rain doesn’t seem to work. So the application guidelines are narrow for such an expensive product. In the past we have discussed including this option in the budget but determined to adapt to the problem as it doesn’t occur ever year.
There are a couple of fungicides that appear to irritate them to the point of moving them off site. There isn’t much research on this, just general observations throughout the industry. We do use them in the spring and late fall on the fairways and I do believe it helps, just not under the pressure we had here with the 4’+ rain we received over that week.
I will be adding the problem to the next Green Committee meeting agenda for discussion. We will add an additional fertilizer application to the fairways that received the most damage to hasten their recovery and hope for some drier weather, although the forecast for the next 5 days doesn’t indicate any relieve!