Poa Greens Explained

If you're curious about why the greens on your course look the way they do, Morgan Creek Superintendent Alan Ayres has the answers...

Ayres recently posted two articles to Morgan Creek's blog that are must-reads for any golfer who wants to understand better why greens in BC are the way they are and look the way they do...

Here we summarize / excerpt from his excellent writing to explain why your course's putting surfaces are likely primarily Poa Anna (Annual Bluegrass) and why this can be an issue when the weather does not cooperate.

Most greens in BC start as seeded Creeping Bentgrass (see image above right). Preferred for its dense, lateral growth, this darker green, slightly blue-tinged grass thrives when mowed to very low heights and exhibits greater resistance to environmental stresses... all great for putting surfaces.

Native to British Columbia, Poa Annua see image above left) is a light green turf species that is sometimes not liked on courses given its pale colour (especially when compared to the Bentgrass) and its vulnerability to temperature extremes.

It is, however, quite resilient. Golf courses frequently train staff to remove small patches of Poa from what started as Bentgrass greens aiming to preserve a uniform turf colour and consistency.

Despite these best efforts, removing Poa Annua is ultimately a futile battle.

For this reason, almost all courses adopt maintenance strategies to manage this reality, focusing on the overall health and appearance of the greens. This management occurs through specific mowing and fertilizing practices to minimize the appearance of different turf species. Poa Annua also demands intensive care, including frequent mowing, fertilizing, and specific watering needs. Over-seeding efforts primarily aim to reintroduce Bentgrass, yet it remains a continuous struggle.

Last Fall, the issues related to Poa Annua greens came into sharp focus.

Courses across the province saw very warm temperatures into early winter. When this was closely followed by extreme cold (with wind chill factors reaching -15C), there was severe drying of greens. This meant that the Poa did not have the time to properly acclimatize to the cold.

Greens were devastated by this and superintendents have had to react. Many in the Lower Mainland made the tough decision to close greens and do an early year aeration to stimulate root development followed by overseeding with the more resilient bentgrass.

Recent good weather has helped the recovery and the courses that made the decision to use temporary greens early on will likely be able to open up pristine putting surfaces by early/mid-May.

You can read Ayres' full articles at the links below:
March 2024 Spring Greens Update
Poa: Friend Foe or Frenemy?

You can read a very in-depth piece about Poa from the USGA HERE