Let's go Roots, Let's Grow!

I apologize for the long break since our last post, as you can imagine it has been very busy around our Turf Care Center lately. In this entry we will cover some of our key practices to focus on root growth and combating Take-all patch.

It was around this time last year that we had a serious outbreak of the disease Take-all patch (Gaeumannomyces graminis) on our greens.

Take-All Patch, 1st Green, June 2012

Take-all Patch is a fungal disease of bentgrass roots that is difficult to detect until heat and drought stress make the symptoms become evident. By this time it is too late, the damage has been done. The plant's root system have been compromised, the plant is not able to absorb water and nutrients and therefore cannot cope with the stresses of heat and drought.

This year we have taken preventative measures to avoid another outbreak like the one we had last year. This plan involves spraying fungicides and focusing on doing everything possible to encourage root growth. This includes adjusting fertility, irrigation and cultural programs (topdressing, aerating, etc.) to favor the plant over the disease. In each one of these practices we have pointed everything towards root growth, you might even go as far as calling it an obsession. I might even name my first born child "Roots."


A brief outline of our root growth maintenance practices:
-Spraying fungicides when soil temperatures are in the optimum range for Take-all patch activity.
-Irrigating less frequently to dry out the greens, encouraging roots to drive down searching for water
-Lower nitrogen and higher phosphorus to encourage root growth over shoot growth
-Bi-weekly applications of foliar fertilizer products that stimulate root growth
-Application of sulphur to lower pH of soil to favor plant over disease
-Applications of manganese and magnesium (which are unavailable in the soil at high pH) to increase plants natural defenses against disease
- Placing hole locations in different areas to disperse traffic
-Topressing regularly to decrease thatch and increase firm/smooth putting surface
-Aeration to open rootzone for gas exchange, and create pathways for nutrients, chemicals, water and sand to penetrate thatch, while providing and easy route for roots to drive down.

Our Foreman Cam Carnegie operating the Aerator on the 16th Green

On May 15th and 16th the conditions were finally right to undertake our first aeration of the year. We did some testing and experimenting on one of the putting greens to play with different sized aeration tines, spacings, depth and speed. We decided to go with a 3/8 inch solid tine on 2.5 inch spacing going to a depth of about 3.5 inches. We felt that this less aggressive form of aeration would still allow us to achieve the desired effect without causing a lot of mechanical damage to the plant.

Tine Action

Aeration Tine Holes

Following the aeration we topdressed with sand and then brushed and rolled to help push the sand into the aeration holes. This will help keep the holes open for gas exchange (oxygen in, carbon dioxide out), and make penetration of water and chemicals such as fungicide and fertilizer much easier. This will also help to further dilute the organic thatch layer while providing a channel for better root growth . With the solid tines the greens were also ready for play immediately after, and many golfers were not able to tell we did an aeration!




While the aeration holes were still open, we followed with an application of fungicide to ensure we would get the chemical into the soil, where the Take-all patch pathogen is active. Soil temperatures were recorded at 15 degrees Celsius, right in the wheelhouse of Take-all.

In the weeks following aeration we have been taking many soil profile samples to monitor root growth.

Soil Profile, 3rd Green, Root Depth at least 4.5 inches

Thick white roots, 4 inches down

Aeration hole profile on 18th green, root growth in channel noted.

 So far we have been pleased with the results of our efforts to grow the roots and combat Take-all Patch, but however pleased we may be, we are still never satisfied.

We have noticed some Take-all activity, primarily in collars, where we may have missed during an application.

This spot has all the earmarks of take all patch. See how the small poa annua grass patches have survived, while the bentgrass has gone a brown, orange colour. The good news is that we can see small new bentgrass plants regenerating. We suspect this area had high activity of the pathogen, but was irradiated by our fungicide application, May 18th, following aeration. Signs like this help confirm that our practices are keeping the disease at bay and our root depth and plant health helps to reinforce this.

We must also give thanks where thanks is due. Our Turf Care Crew of 7 staff has done an absolutely amazing job in maintaining the course to its current conditions. Their experience and work ethic has been instrumental in our success so far this season.

Mother nature has also been very kind to us so far this year. From our mild winter with long, protective snow cover, to a warm and relatively dry April. But try as we might, as Turf Managers, we are always at the mercy of Mother Nature. Lately she has provided us with a very wet few last weeks. This has helped everything on the course get green, however, it has slowed our greens speed as the greens stay wetter from the rain, and more importantly, has restricted our ability to manipulate the moisture of our rootzone, possibly impairing root growth temporarily. The good news is the forecast for next week is looking much better, and we hope to be able to continue on with our root growth practices. Lets go roots, lets GROW!