Grass Type

Continuing on today with the series on what makes greens great, I thought I would touch a bit on grass types. They can make a huge difference in the quality of a green, from how well they roll, to how well they stand up to temperature extremes. How we maintain our greens via cultural practices (topdressing, verticutting, water, ect ) also plays a big role in what species of grass wins out. The two main species we deal with here in Atlantic Canada are creeping bentgrass and poa annua (fescue is also a consideration, but there is only one course seeded out to fescue at this point, so we will see how it goes).
 Most of the older courses you would play around the Maritimes (older than 20 yrs) are predominantly poa surfaces. Over time many people in the industry think that poa dominance is inevitable and they maintain for it. The courses that were built over the past 10 years or so would still have majority bentgrass surfaces, although many would be on the slow road to poa.  These courses would have been seeded out to a newer strain of bentgrass and depending on the cultural practices employed, they would have varying amounts of poa vs bentgrass in their greens.
 People ask me a lot what the difference is between the two species of turf. Well the best way to answer that is to feature each one, give some pros and cons, and let you decide. Most who know me know which one I prefer, but that by no means makes it right. So let's start with Poa...

Poa Annua

• What it likes...
    - lot's of water (frequent small amounts)
    - lot's of fertilizer
    - to be disturbed (via cultivation like verticutting)
    - openings or voids in the turf stand. Poa is a very opportunistic grass that will fill in any void it can.

• Positives
   - it makes a fine putting surface if you can control the seed head development
   - it recovers really quickly because of prolific seed head production
   - it will fill in bare areas of turf (if you want it to)

• What it dislikes...
    - lack of water
    - lack of fertilizer
    - the winter...especially ice cover.
    - the heat of the summer
    - to much traffic
• Negatives
  - susceptible to winter kill (although it can bounce back...by July)

 
   - seed head production makes for bumpy surfaces for putting

   - they have very shallow root systems that make it tough to maintain in the summer.

 So poa has some positives and some negatives for sure. That said, a lot of the best courses in the world (Pebble Beach, Oakmont) have poa surfaces. They also have lots of money to maintain them.

Creeping Bentgrass

• What it likes...
   -  deep and infrequent amounts of water
   - small amounts of fertilizer
   - to be left alone
   - low mowing heights

• Positives
   - deep roots

                                                             That's from #7 green today
 
     - will stand up to disease better than poa if maintained properly
     - makes for a wonderful putting surface
     - holds up well to traffic
     - it generally holds up to winter and deals with ice cover better than poa (but when it dies it does not    come back!)

• What it doesn't like...
    - to much water
    - to much fertilizer (both cause to much thatch production)
    - to be disturbed (if done at the wrong time it allows poa invasion)
   
 • Negatives
  - it can be a prolific thatch producer and becomes very prone to certain diseases if maintained incorrectly.
  - can be slow to wake up in the spring
 

 So there you go, an abridged version of the two main species of turf we use on our greens. Like I said, both can be great putting surfaces, but in the end I will always chose bentgrass. There is a slow movement away from poa in the industry at this time (there are even chemicals that will eradicate poa but not harm the bentgrass) and even a new way of looking at bentgrass maintenance that will allow it to become an even more sustainable species of choice.


PS     The other turf one could choose  is a fescue mixture. Many of the older links course in the UK have predominantly fescue surfaces and they work just fine. Fescue is probably the most sustainable choice for greens, as it requires little in the amount of water, fertilizer, or fungicides. It does not, however, stand up well to any amount traffic (read, no golf carts). The the course I mentioned earlier is the soon to be opened Cabot Links, located in Inverness NS. It will be interesting to see how these surfaces hold up to the rigors of Maritime winters and the inevitable traffic form a full golf season...stay tuned.

  Thanks for reading
paul m