Preparing Sprayer for Dormant Zoysia Pre-emergent/Poa Control

Since I had to come in this morning to open the course, I decided to check spray rig before the next round of below zero temperatures settles in.  Within the next couple of weeks, we will be making our yearly Dormant Zoysia Pre-emergent/Poa control application to our fairways, tees and green surrounds that are covered in zoysia/bermuda.

This application includes a pre-emergent product Ronstar Flowable and non-selective herbicide Glysophate product for post-emergent on our fairways to control crabgrass/goosegrass/poa/other weeds and will kill already germinated poa annua that has popped up in the warm season grass since last fall.  We still need to do some off season work on the sprayer but the main thrust for checking it out was to insure that it is pumping properly before this very important winter spray application.  We try to spray on a sunny day when temperatures are above freezing and the ground can handle the sprayer driving on it.

Poa annua will become active in above freezing temperatures over a few days and will pull the material into its system and the herbicide will kill it over a few weeks.   It is only safe to spray this non-selective material during dormant periods in the dead of winter or it could hurt the warm season grass or delay it breaking dormancy.  The pre-emergent is sprayed onto the turf surface and prevents the shoots of the undesirable weeds from growing which kills the plant.  It is different chemistry than  other pre-emergents that inhibits roots from growing, including your turf grass roots.  If you ever hear someone saying that a pre-emergent is root pruning, that does not occur with the product we use.  It is not as price competitive as other products but when we are spraying over 30 acres like we do our tight zoysia areas, why would we not want the best product for the health of this large area of turf!  

The Glysophate spray will prevent little clumps of poa annua from interfering with play during the early part of the golf season.  It will also help to reduce the seed population of the poa annua which is a prolific seeding plant and will reduce competition in some of the less than ideal growing spots that we have on the course for the warm season grass.  Mainly shaded and or high compaction or traffic areas.  As the warm season grass is weakened, the poa annua or other weeds have a tendency to move in and attempt to reduce the warm season grasses ability to grow properly through competition for sun and water.

Still a few weeks away but the season will be upon us before we know it!