Earthworm Casts And Frost Delays November 11, 2014 By Darin S. Bevard

Heavy earthworm casts can affect maintenance and playability. Cool, wet fall weather provides ideal conditions for earthworms. At this late point in the growing season, simply managing the casts – and not the earthworms – is the best approach to maintaining playability.

During the latter part of the growing season in the Mid-Atlantic, preparing golf courses for daily play can be challenging. While the worries of hot weather are certainly gone, the changing weather creates new problems, like leaf removal, that are more of a nuisance than major issues. Additionally, earthworm casts and frost delays have been recent topics of conversation.

Earthworm casts affect maintenance and playability. In severe cases, fairways cannot be mowed until they are dry and dragging is performed to break up the casts. Wet earthworm casts can smear fairways and will affect the performance of mowing equipment. The combination of slower turf growth and less frequent mowing makes the casting problem more severe. Fertilizer products containing tea seed extract can be applied to irritate earthworms and reduce casting. However, at this point in the growing season, it may be best to simply deal with worm casts as the season comes to a close. Remember, earthworms benefit soil structure. It is only the casts on the surface that are detrimental to grass and playability.

Frost delays can be discussed every year, but the bottom line is that there is great potential to injure frosted turfgrass by introducing traffic. Frost also delays maintenance operations. Golfers are ready to go as soon as the sun is up and the frost is gone. However, remember that the maintenance staff cannot blow leaves, mow or perform other course setup tasks when frost is present. Therefore, some patience and understanding from the golfers is required. Realize there can be an additional delay after frost has burned off so the maintenance staff can get a head start on course preparation.

Late season is not mid-season. Golfers can help by being patient and understanding the challenges that maintenance operations must contend with when preparing for daily golf as we progress towards winter.

Source: Darin Bevard (

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