Poa Annua

Right now there are many things happening on the golf course with Poa Annua.  We talked in the last post, Poa Seedheads - Proxy, about the production of seed heads and how we control them.  There are also many examples currently occurring on why Poa Annua is a weaker and undesirable specie of turf on the golf course.  First we have the production of seed heads, affecting the playability and populating the soil and matt layer of our golf course with seeds that are ready to germinate whenever the opportunity is right.  Any opening in the turf canopy from a divot, a ballmark, a worm casting, mechanical damage from golf carts or mowers, or any disturbance to the turf causing an opening allows the seed to germinate and grow.

Overall poa is a very week specie in the family of turfgrass.  It does not perform well in cold or hot conditions.  Last month when the turf was first coming out of dormancy, I posted about the bentgrass growing and the poa having a sunken appearance on the greens because it was slower in breaking dormancy and was not growing at the same rate of creeping bentgrass.   We will see very similar conditions in the heat of summer, June, July, and august; the Poa will appear struggling while the bentgrass will be doing fine.  Poa is also much more susceptible to diseases.  Right now we have small areas in our fairways that have become inoculated with Pink Snow Mold disease, all of the turf effected by pink snow mild is Poa and the bluegrass and bentgrass in the fairways have no signs of the disease.

Tan areas are infected poa, greens areas are creeping bentgrass


 

 

During the growing season, Poa requires more water, more fertilizer, and a higher degree of maintenance.

 Poa Annua makes management of a turfgrass stand very difficult.  It is difficult to keep out or eradicate.  Once you get a high percentage of it then you are managing it, leading to  a very intense “babysitting” program in the heat of the summer.

Every golf course you go to will have some population of Poa Annua on it. It is very hard to control because of many different genotypes, and very versatile to adapting to any condition.  There are a few ideal climates where the high temperature is around 80 degrees every day, low humidity leading to a lack of disease pressure, and higher amounts of precipitation creating a nice germination of continued seed production.

In summary:

A.      Poa is very difficult and challenging to keep out, it exists in some population on all courses.

B.      A very rapid seed producer, increasing its reproduction chances

C.      Many different genotypes exist

Once you manage it, then you will deal with;

A.      The production of seed heads affecting playability

B.      A week specie in hot and cold conditions

C.      More susceptible to diseases

D.      Higher requirements of water and more fertilizer

E.      The ability to adapt to any conditions – mowing height, traffic, compaction