More Sand

For a variety of reasons, our greens have a tendency to get puffy and soft as soon as the weather starts to get hot and humid.  It is caused by a combination of factors including lack of subsurface drainage as well as excess organic matter in the rootzone.  Also, the bentgrass on our greens was originally seeded to a variety called 'Penncross', which was one of the very first turfgrasses ever to be genetically bred back in 1955.  While it is still regarded as a decent bentgrass cultivar, it isn't the greatest.  Part of its issue is that it has a tendency to separate into genetic clones of its self over time, leading to a very distinctly mottled appearance.  Apparently, some of these clones have the tendency to get softer than others, which leads to small scalped patches on the greens as we get down to our summer mowing height of .125"

Genetic separation of Penncross is very evident in the spring as all the
different clones green up at different rates.

There are really only two solutions to this problem.  The first is water management.  We have been making a very conscience effort this summer to use our new moisture meter and keep the greens as dry as possible, without letting them get too dry.  It has proven however to be a very difficult challenge to effectively manage the moisture on the greens with our outdated and inaccurate overhead sprinklers, meaning we have to rely on handwatering, a lot.  That is very difficult somedays with our small crew.

Our other weapon against soft greens is sand.  I have a love hate relationship with sand however.  I love how much it helps to firm and smooth the greens surface.  I hate how much it destroys the reels on our mowers.  Regardless, it is a necessary evil.

We topdressed the greens with another good coat of sand today, only 2 weeks after the last application.  Hopefully the greens will respond well and should pick up some firmness and speed in the coming days. 

We also tried a new method of incorporating the sand into the turf canopy this time as well.  Our Penncross/Poa Annua greens aren't very dense in comparison to newer Bentgrass stands, so instead of using a brush we used our greensroller.  Furthermore, we utilized the spiker attachment on our roller at the same time.  This helped to not only get a little bit of the sand worked down into the top of the rootzone, but also helped to open up the surface of the greens to allow better oxygen exchange with the roots, which is extremely important this time of year with the heat and humidity.

Throwing sand.  A relatively heavy application for the middle of summer.

The roller/spiker combination did a great job of pounding the
sand down into the canopy.