Tuesday, July 12, 2016

"Brown Spots, and what causes them..."

I was asked a good question today and thought I would share this with others.  A member asked, "What causes the random brown spots here and there in the fairways and roughs?"

Excellent question. There are a couple ways to look at this. One answer is the phenomenon of localized dry spots. GCSAA defines this as: 

Localized dry spots (LDS) - sometimes referred to as isolated dry spots, dry patch or hot spots - can be defined as irregular areas of turfgrass that, for no apparent reason, begin to show signs typical of drought stress. Possible causes of LDS include excessive thatch, compacted soil, poor irrigation coverage, steep sloping grade (water runoff), high soil salinity, improper chemical usage, insects, diseases and water-repellent soil.
 
The best way to treat this is through products known as wetting agents, which are essentially a soap like product that reduces water tension and allows the soil to absorb water again. Did you ever pot up a new plant using a peat moss based potting soil? You may recall how difficult it was to get the peat to absorb water because it was so dry? Soils work the same.

In Highlands, our turf is accustomed to heavy clay soils and a temperate rain forest climate. This is a recipe for a shallow root system. Simply put, we aren't accustomed to periods of extreme drought. Our antiquated irrigation system from the 1980s does an extremely poor job delivering water where it is actually needed and this is why we spend so much time dragging hoses around the course. Furthermore, our fairways are comprised of a stable mix of bentgrass and Poa annua. Poa annua tends to be a much more shallow rooted plant compared to bentgrass. When it gets dry, the Poa will dry out and wilt first because of this. This mix of tursuddenly looks noticeably patchy due to one species holding on longer than the other. Therefore, if we were going to manage the golf course to stay perfectly green, we would have soaking wet fairways. We would need to overwater the bentgrass in order to keep the Poa alive. 

All this said, let's face it...this is a rare occasion and one we only deal with every so many years.  I would rather focus on the playability aspects of the course, keeping the aesthetics a close second. I thing everyone likes, is the additional ball roll. In green committee meetings, when the irrigation system replacement conversation comes up, it's often met with members who feel it's a low priority given our average weather stats, and understandably so.  But the fact remains, you can't have it both ways. Until we make that investment in the future, there will be years like this with occasional drought.  That means dealing with a little brown here and there. We are not equipped at Highlands CC to maintain a wall to wall green golf course during times like this. It simply isn't possible given what we have to work with. Irrigation systems are meant to supplement rainfall, not replace it. Again, we are watering and area that is 60 yards wide by 40 yards long with one single irrigation head that puts out over 120 GPM. That was outdated technology in 1985, let alone 2016. Today's modern systems using more sprinkler heads, much smaller in size to pin point irrigation needs. This means mist heads on bunker faces, small heads that can even irrigate the bunker sand to ensure it is most playable each day. This means giving the superintendent total control of watering- irrigating roughs only or fairways only depending on the goals.  One sprinkler head can't do that, no matter how hard we try. A little brown isn't a bad thing, however.  When normal rain resumes, it will recover just fine. In the meantime, enjoy the extra yardage on your drives!  In Highlands, it won't be long before we are complaining about too much rain!