Friday, August 3, 2012

The Dog Days of Summer 2012

"The Summer Demands and Takes Away too Much."
John Ashbery

The  Ancient Romans who associated the Dog Days of Summer  with the rise of the "Sirius" or the "Dog Star". According  to Wikipedia they even sacrificed a brown dog in an attempt to appease the rage of Sirius believing the star was the cause of the hot, sultry weather. Although my research has led to differing dates of the "Dog Days", I consider them right now, the next 50 days between the beginning of August till the Fall equinox in mid to late September. 

These are the days  that the cool season turf at Granite Bay  can start to fade and thin in areas. The time in which certain opportunistic weeds start to emerge and take hold and disease pathogen's thrive. The time in which the bentgrass in our fairways start to get soft and the hybrid bermuda on our tees thrive. In short,  the Dog Days always have been, and always will be the most stressful period for this golf course requiring an all hands on deck approach to get us through with a minimum of casualties.

Irrigation Management Improvements 

Granite Bay GC weather station.
Our own weather station which collects hourly / daily
high / low temperature readings, humidity, wind speed and
solar radiation (Langley's)
Thankfully so far the summer season of 2012 has been fairly mild. We have had three periods of triple digit temperatures through July but they have been followed by cooler weather ushered in by the delta breeze and most importantly low evening temperatures. This type of weather certainly makes the battle easier, but we still have cool season turf  that would prefer maximum temperatures in the 80's growing in heavy decomposed granite soils. We still have to irrigate nightly and although we have great water quality to irrigate with, it still does not readily move through the heavy native soils. This requires an intense micromanagement of the irrigation system that I believe our GCM staff has gotten much better at and with future infrastructure improvements can improve even more.

Granite Bay of course has an automatic irrigation system which has a central computer that assimilates  weather data provided by our weather station and in turn calculates a  irrigation replacement quantity based on what is known as an evapotranspiration rate. This central computer has a software program called Cirrus which has a myriad of ways to apply this calculated ET rate to the site specific areas of the course. But it is not as simple as turning on a switch and letting the computer take care of everything. On a golf course there are  different types of playing surfaces, different species of turf and different sub and micro climates. Examples are shady area's  versus a south facing  hot bank's or hillside's. Topographical differences of a mound versus a low lying area of a fairway along with  different native soil types on one property and the modified soil types (sand blends) of the greens and tees are examples as well. All of these micro climates have different irrigation requirements that have to be taken into consideration. Sometimes the same irrigation heads or stations cover adjacent conflicting areas that have distinctly different irrigation requirements. All of this necessitates an intense micromanagement of the irrigation system. 

Screen shot of  "program detail" from our  Rainbird
Cirrus Central irrigation Computer located in the GCM offices.
This central computer is the brains of the irrigation
system and is where all run times are calculated,
adjusted and started.
Therefore one of the best management practices we have developed for Granite Bay, and are continuing to fine tune are daily individual station adjustments to the  automatic irrigation stations and heads throughout the golf course. Through the Cirrus software in the irrigation computer we can manipulate percentages of ET up or down based on conditions on the ground of individual stations and heads. In extreme situations where an area has become over wet or dry we can temporarily adjust the station up or down or off for a specified amount of time again based on these conditions. Stations are grouped in the software by golf course nomenclature such as greens, tees, fairways and rough and are put in programs that can be adjusted by area type and hole as well. The first line of micromanagement of the system is making these adjustments on a daily basis based on that days conditions. 

Jogi making daily irrigation adjustments to individual
stations and sprinkler heads via an IPad

IPad connects to the central Ranibird computer
wirelessly allowing for efficient, real time changes
 on the course exactly where we need them. 

We typically maintain program averages within Cirrus below our the ET rate that is calculated by the weather station. At Granite Bay we have found that  maintaining these percentages at the calculated ET rate results in undesirably wet conditions. Running programs below the adjusted ET rate necessitates the second line of irrigation of micromanagement, hand-watering. We have made a tremendous amount of infrastructure improvements to the irrigation system the past few years improving irrigation coverage and have more planed in the future. All of these changes have improved conditions throughout the course and have taken the strain off of our hand-watering regimen. That being said there will never be a substitute for a man on a hose. Irrigation systems at best can be 60 to 70 % efficient as compared to rain and if we purposely water below adjusted ET rates to avoid overly wet conditions at Granite Bay we must supplement with guys on hoses putting water exactly where it is needed.

Hand watering is the backbone of  micromanagement
of the irrigation system. There is no substitute for a
guy on a hose

Screen shot of our weather / irrigation tracking
which showing 2012 YTD water usage below the
adjusted ET rate. In the past when this line has been
closer or even over the ET rate the course has
been too wet.

Watering Putting Surfaces based on Volumetric Water Content

Another industry wide best management practice is the use of moisture sensors to determine volumetric water content or VWC and irrigating based on this data. The use of property wide VMC as a substitution to ET based program's could change the way we look at irrigating golf course turf but are still aways off from perfection.  However the use of hand held meters checking the VWC of putting surfaces has been noted as a best management practice by the USGA Green Section for some time. We have been using a Spectrum Technologies Field Scout TDR 300 soil moisture meter diligently for the past couple of months and are starting to experience good results from it's use. We check the putting surfaces in the morning and record VWC averages and note highs and lows and hand water and adjust individual heads according to the data we collect. Additional readings are taken in the afternoon giving us further data to work with. We started using the meter in reaction to inconsistencies and a nagging pythium root rot issue. Even though the daily use of the meter has added to our maintenance program, I believe that the data collection and adjustments based on  this VWC data will be a big help with surface consistency and health moving forward.

Gama checking and recording VWC data.
This has become a every morning task.

Spectrum Technologies Field Scout TDR 300
soil moisture meter.

Granite Bay's Irrigation Future

We have many plans for the future having to do with the irrigation system. We hope to finish all of the irrigation coverage issues this coming winter. When Mitch works his magic with corporate and gets the capitol funding we submitted released early,  we will be off to the races this winter and will get this work completed before we start irrigating in 2013. As I have stated many times before, without exception every place we have completed this irrigation enhancement work has resulted is superior turf and a much reduced need for labor intensive hand watering. Secondly we have some irrigation as-built mapping to take care of that will give us the kind of information we need for further 2014 irrigation enhancements which will give us single head coverage enhancing even further our ability to micromanage. More on this to come.

Given the importance of irrigation here at Granite Bay all of these type of improvements will help us micro-manage the irrigation system creating better conditions in the future Dog Days of Summer. And the one thing we can count on every year is that the Big Dog will be back.

"I purpose to fight it out on this line if it takes all Summer."
Ulysses Simpson Grant 1869

1 comment:

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