Bentgrass vs Poa

I thought it would be interesting to show the rooting difference between bentgrass and poa.  I pulled two plugs from #17 fairway, one bentgrass plant and one poa annua plant.  The picture below speaks volumes.  The bentgrass roots extend to 6" vs the poa plants 1.5".  This is one reason the bentgrass is more heat tolerant and requires less water.  The longer root system is able to pull water from deeper in the soil profile creating firmer playing surfaces on top.

The extremely short roots of the poa annua does not provide much water retention.  Subtle changes in the weather like increased wind or a drop in humidity can rapidly dry out the plants.  The root system can not retain enough water to make it through a high evapotranspiration day.  This is why we have to syringe or spin the irrigation heads in the afternoon.  As we increase our bentgrass population, the fairways will become stronger and stronger requiring less water and firmer conditions.


bentgrass plant vs poa plant from #17 fairway
  

The bentgrass that we have been seeding into the fairways has begun to germinate.  The cool nights forecasted for the rest of this week will be extremely helpful in the continued success of the seedlings.  I would anticipate pretty good growth this week.  The recovery will not be instantaneous, but the spots will keep getting smaller and smaller as the new plants germinate and the existing bentgrass creeps into the thin areas.  Please continue to avoid driving through the seeded areas.  The less traffic on these areas, the better off the plants will be.