One of the big topics in regards to the putting surfaces this season has been the presence of grain. “More than they have ever had” and “they are different than they used to be” are two comments I have heard from members. There is no doubt our greens have a good amount of grain and this is the case primarily for two reasons.
Northland has a tremendous amount of bentgrass, not just bentgrass but older varieties of bentgrass, which tend to have a strong grain. Most of the bentgrasses on our greens were designed to be mowed around 1/4 of an inch. Due to this these plants have a small number of leaves per plant. When mowed at today’s heights on putting surfaces these bentgrass plants adapt and survive by growing laterally producing grain.
The second reason for the strong grain on our greens is the tremendous amount of property slope. Grain grows downhill and the stronger the slope the stronger the grain.
Are our greens grainier than in the past? Yes, because we have greater populations of bentgrass. The photo below was taken last week from one of the greens at Town & Country, the course I worked on before coming to Northland. When I first saw Northland’s greens I remember them being very similar to what I was seeing everyday at Town & Country.
You can see this green is mostly Poa with bentgrass also present. You can also see that the bentgrass present is all growing towards the bottom of the photo; downhill. If the greens at Town & Country had a higher bentgrass population they to would be grainy as well.
The next photo is one from a green at Northland. Here you can see a much great amount of bentgrass, which is also growing towards the bottom of the screen, again, downhill.
Grain can never be eliminated. Bentgrass plants will always have a desire to grow down hill and thus they will form grain. There are methods we use to keep the grain under control. Vertical mowing or verti-cutting is a practice that has many uses in managing golf course turf. However, it is damaging to the plants, disrupting to the surface and offers the opportunity for Poa annua intrusion. All of the uses for vertical mowing are able to be completed by other, less invasive tasks; tasks which are employed here at Northland.
The two items below are the ways in which we control grain here at Northland:
Brushing-As our bentgrass populations have increased the need to brush our greens has become much greater. This post northlandgrounds.blogspot.com/2011/06/brushing-greens.html from last summer talks about brushing putting surfaces. We used to use a pull behind broom to lift the turf before mowing. For many reasons we switched last season to a brush mounted on the green mower. This year we have increased the number of brushes to include each mower. This allows us to brush every green, every time it is mowed if we desire.
Height of Cut-With cooler weather comes a greater ability to lower the height of cut on putting surfaces. The lower the height of cut the less grain becomes a factor.
As long as we have bentgrass putting surfaces we are going to have grain. Even the newer varieties of bentgrasses, which have a much more upright growth habit, would have some amount of grain on our sloping greens. Of course a conversion to the newer bent varieties is highly unlikely here at Northland, rendering the point moot.
Chris is the superintendent at Northland Country Club in Duluth, Minn. Check out his blog at www.northlandgrounds.blogspot.com