Sunday PM
The golf course is performing well during the first weeks of a hot summer. Greens have recovered nicely from the damaging nematicide application except for 15 which lags behind. 15 green is being pushed for growth and we expect lateral growth will fill in voids soon. (More on the nematicide application below....for true turfnerds only) All other greens are back under growth regulation and have sped up a bit the last few days.
Fairways are in excellent condition but have shown us signs that extra aeration procedures are needed this fall. Even during our wet early summer, when probing just below the surface, sometimes soils are drier than they should be. This tells us we need to more aggressively break through that top layer of thatch and provide channels for water to enter soils.
Aerating Potowomut fairways with conventional equipment can be an adventure because of stones and rock that is close to the surface. Equipment fails, aeration tines are quickly ruined and our patience is always tested. This year, however, we will alter our methods to accomplish the task. We will use solid tines instead of pulling a soil core. Using solid, index fingered shaped pieces of steel to aerate will break through the layer of thatch and help us accomplish our goal. It is our intention to aerate all fairways and intermediate rough twice. Sometimes, more is not better, but in this case it is! We also plan on experimenting by applying a thatch elimination chemical to a fairway or two this fall and will report our results late in the year.
Golf course water use has increased with hot and dry weather. During the last eleven days we have used 2.5 million gallons. (Total season irrigation stands at 8.9 million gallons) Our small well has trouble keeping up with the heavy demands of summer, so we have been purchasing supplemental water from the city of Warwick. (So far estimated at 460,000 gallons) As always we try and use, and thus buy as little water as possible.
Also please remember that the effective width of the irrigation system is about 74 yards across each fairway. Beyond this width, turf sees no irrigation and is prone to go dormant until September. Most rough is not irrigated! Please be patient...remember the green color will return! Personally, I enjoy the many different colors the golf course presents to us through different seasons.
During the next few weeks we will be working to add more sod plugs to a few spots on greens. The poor turf area of 9 fairway will be sodded. Weed and nutsedge control will continue to all areas. The golf course will be treated for grubs during the next two weeks. The new Otterbine fountain in the pond continues to have problems staying running. Service technicians will be here again on Monday.
SPECIAL SECTION FOR TURFNERDS ONLY....DETAIL ABOUT NEMATODE ISSUE AND THE APPLICATION OF JUNE 19. NON TURFNERDS READ AT YOUR OWN RISK!!!
Potowomut greens have perennial populations of plant parasitic nematodes, especially one species....the stunt nematode. Longtime members and employees tell me years ago the golf course was annually closed for a day during summer to treat these root destroying pests. In early June, we had populations ranging from 4800 to 6600 stunt nematodes per cup of soil from the four greens sampled. Other damaging nematode species were present but not at damaging levels. When a single sample contains 500 or more stunt nematodes, turf damage on greens is possible.
Nematodes are common on golf courses of Potowomut's age because we have been growing the same crop (turfgrass) for many years. Farmers rotate crops almost every year to avoid hosting a single damaging pest but in golf, that option is not available.
Nematodes are the most populous animal on earth and are present in all soils. Most are beneficial; hardly any are parasitic. Stunt nematodes are aquatic animals....living in water films between soil particles. In agriculture, they cause estimated $ 10 billion damage annually to crops. Golf course turf is a perfect living environment for them as we irrigate turfgrass to sustain life. With each irrigation cycle, we also keep our billions of nematodes fat, healthy and reproducing. Every action we take to maintain turfgrass and turf roots keeps nematode populations high and maintains the potential for damage from them. The old dog chasing its tail is an analogy that works well here for turf maintenance guys like us.
Previously, we had a chemical available that controlled plant parasitic nematodes, Nemacur, made by aspirin maker Bayer. Nemacur was an extremely hazardous product to both applicators and golfers and it was pulled from the marketplace in 2005. (Unfortunately for me, it was readily available when a partner and I applied tons of Nemacur to 28 acres of fairways in the 1980's on 95 degree days with old hand Cyclone spreaders. One word….nasty!) After 2005, turf managers had a few unreliable methods available to control a significant golf course pest. Last year, Agrium Advanced Technologies introduced Multi-Guard to turf managers and I for one was intrigued.
Because of high populations, we applied Multi Guard (chemical name furfural) on June 19, and saw turfgrass damage on June 22. Damage was minor, except for 15 green where it was more severe. Calls were immediately made to the seller of the material who contacted the chemical manufacturer, Illovo of South Africa. Lucky for us, their Commercial General Manager (and product developer) Dr. Greg Burger was in Washington DC meeting with the United States Environmental Protection Agency, and he visited us at Potowomut last Thursday evening with Vice President Jonathan Myers of Agrium Technologies, the US seller of the product.
In short, I received a short but detailed nematode education during the meeting. Fellow turfnerds, I wish you all could have been there! We learned plenty during our discussion and I believe we have a much better handle on nematodes in general and on designing a plan to control their numbers at Potowomut.
The chemical furfural is a byproduct of Illovo's sugar cane production operation. It is a 100% natural product; it is not a manufactured chemical. The work on the chemical began in 1994 and it has been successfully used in South Africa, mostly on "football" pitches for years. The company's goal, and one that I am sure is exciting investors everywhere, is to get furfural registered for use on food crops in the United States. Dr. Burger says he thinks they will get there.
Dr. Burger observed extremely short (less than a half inch) root systems on Potowomut greens, especially where damage occurred. He says he sees short roots wherever his nematode travels take him and our symptoms are common. He concluded...and I agree that nematodes are the cause. He did provide us with direction in managing these nuisance pests.
The chemical works by dissolving away the nematode's outer layer. Therefore, the chemical must get in contact with the little buggers in soil. This is why we were advised to apply .25 to .50" of irrigation water to move the chemical to where the nematode lives. We applied .35" of irrigation immediately following our application.
Dr. Burger suggested a few changes regarding our application. First, he advises that soils be at 70% of field capacity during application of the chemical. A soil at 100% field capacity is one that cannot accept ANY more water, in other words apply furfural to wet greens. With our big and heavy sprayer, this is a difficult but not impossible task to achieve. A viable plan I believe is to irrigate to field capacity, apply chemical, irrigate chemical in, then bring out the rollers to tire tracks!
Secondly, he advised us to apply a wetting agent just prior to applying furfural. Wetting agents help to draw water down into the soil profile quickly. The idea here is to move the chemical into soil ASAP. Before June 19, our last wetting agent application was on May 14.
Furfural is not designed as a one shot nematode cure-all. Nematodes won't go away from our soils anytime soon. The goal is to control and knock down huge population spikes that occur during summer months. Therefore, we were advised to plan two or three applications to manage the population. This can be done with the Multi-Guard product, at lower rates than we applied on June 19, 2012.
Back to our turf damage. Most of our damage was on 15 green, of course the green with the highest nematode populations this year and in past years. The back of the green was hardest hit while the more common speckling type damage is present on the front and middle of the green. Poa annua was mostly affected and bentgrass fared better. (No surprise there....bentgrasses always take more abuse from any source!) Not coincidently, bentgrass has stronger roots than Poa annua. Other greens affected briefly have healed. Recently, members have asked me what the big fuss is about because all greens are great!
Dr. Burger told us that damage to turf occurs but is not common. He clearly wanted to understand what happened here and assist us if needed. He advised us in the future to pre-irrigate greens and apply a wetting agent the day before applying furfural. The speckling damage was caused by chemical sitting in small pools created by indentations of tire tracks from our sprayer, and despite all the irrigation we applied, the chemical wasn't helped down into soil by the presence of a wetting agent. Most severe damage to the back of 15 is where nematodes had already done significant damage to stressed Poa annua root systems combined with three 95 degree days after application. He advised us to get on a regular program of controlling populations, using a lighter rate of furfural two or three times per season. I am confident that with our nematode education from Dr. Burger, we can successfully design a program to limit nematode damage for 2013 and beyond with furfural if we choose to.
Why such a long diatribe about nematodes and this one attempt at controlling them? First and most importantly, we wanted to explain with some detail why a chemical application caused damage to greens when applied using label directions. In my opinion, this should NEVER happen. We spent significant dollars to improve turf and yet, it was damaged.
Secondly, true turfnerds like me and anyone still reading know that turf roots are a very important factor in growing successful golf turf. The goal of most all maintenance procedures we perform is to expand or preserve roots. The more roots, the better the turf. Better turf is more reliable and provides the firmest and fastest playing surface for golf. We have been extremely frustrated over the years by our greens' lack of growing significant root systems despite having a high population (and continual promotion) of deeply rooted creeping bentgrasses. Potowomut greens have a history of high nematode populations and they are the one pest limiting our green's performance. We have been patiently waiting for the marketplace to provide us with a nematicide to assist us because nematodes in high numbers can be absolutely devastating to greens, virtually overnight. Over the last few years, we have bought and tried a few new products with no success. None have looked as promising to me as furfural on stunt nematode in our climate. On behalf of our greens and our roots, we will continue to look for the best solution. Thanks to everyone for your continued support. Please feel free to email me with any questions, or stop me on the golf course. And remember non turfnerds, you were warned.
Patrick M. Gertner CGCS
