gauging the amount of available water. If the soil probed to 75mm wets the hands there is too much water present but, if the soil flows like salt, it is probably already too late and grass cover has shown signs of deterioration. Good management can prolong the water storage and the water use rate in turfgrass can be enhanced by the degree of maintenance of the grassed area. Deep tine aeration to create a porous root zone and deeper roots will mean that more water can be stored to a greater depth. Good nutrition ensuring adequate potassium levels also promotes better durability at the time of water stress and increasing the interval between mowing reduces the rate of water loss (Kneebone,1992).
Determining the water need
A simple water balance table revealing a little water stress could take the following form (remembering that after good penetrating rain there is a time-lag before field capacity is reached and ETc values will lessen daily when no water is added). This understanding gives comfort in judging the water available but nevertheless the table only gives a ‘guide’ condition. Only by probing can we judge the variation in water supply in the different locations and aspects and a powdery dry condition should be never
Date
be allowed to develop. Selective hand watering is often the best solution where run-off has developed wetter and drier conditions on a golf green. On a sports pitch with deeper root depth, water storage is greater and conditions are more uniform. Interestingly, the turfgrass plant shows little visual loss in quality with carefully managed deficit irrigation (Kneebone,1992). This simply means applying less water than the theoretical calculated requirement. In practice, aiming to ensure the available water content between field capacity and wilting point is the main consideration and a temporary shortfall causing a little stress is better than too much water - more air is available in the root zone, roots will endeavour go deeper and the grass will be less succulent and develop greater hardiness. Duncan Kelsoe, golf course director at Kingshill Golf Club, in maintaining a weather station able to record daily ET losses, plans to apply 50% of these losses at intervals of two to three days allowing for expected rainfall. There is no doubt that with experience, maintaining a tight rein on water application and continuing with a sound maintenance programme, the water use rate of turfgrass cover can be controlled and even reduced. Restricted watering can be taken to a stress level where grass cover is not
Day Reservoir in Rainfall Effective Irrigation ET crop Gain/Loss Balance 50mm in 24hrs rainfall mm
effective
18.4.05 1 6max (fc) 19.4.05 2 6 20.04.05 3 3 21.04.05 4 0.2 22.04.05 5 -2.4 23.04.05 6 6.0 24.04.05 7 4.2 25.04.05 8 1.7
r+i-e
- - -
15 - - -
- - -
11 - - -
-
- - - - -
2.6 1.4 3.0 2.8 2.6
mm mm (r) mm (i) mm (e) mm c/f mm 4
-3.0 -2.8 -2.6
1.5 9.5 2.8 2.5 2.3
-2.8 -2.5 -2.3
Note: fc is short for field capacity - the maximum water this depth can hold against gravity. Days OFF!
Water run off on a golf green
Water run off on a planted sports pitch significantly impaired.
It now must be evident that as we become more aware of the water losses and effectiveness of rainfall and irrigation we can, with sound management, use water more wisely and produce hardier turfgrass growth that still meets our requirements.
reservoir
6.0 max 3.0 0.2 -2.4
6.0 max 4.2 1.7 -0.6
The Bill Adams Literary Awards were kindly sponsored by Syngenta
Pitchcare would like to thank Simon Elsworth at Syngenta for his assistance and Bill Adams for judging the competition.
Gordon Jaaback wins a Weekend Break for 2 to the value of £500
... or what Pitchcare readers get up to out of office hours
DAVID GOODJOHN - General Manager and general dogs body at GSB Loams for the last ten years. The biggest challenge is to keep my family happy and continue to promote the company whilst enjoying life to the full. I have three children - one daughter, Bernie 20, and two sons Nick 18 and Don 17 who are all in full time education. As for interests outside of work, I am very committed to playing and watching sport. For the last twenty years or so I have regularly played cricket and rugby in and around Kettering. Every year I find myself on either a rugby tour or cricket tour travelling to some part of the UK. I also attend an annual cricket sabbatical to the Isle of Wight each July. My sporting prowess, or lack of it, has certainly enabled me to meet many interesting characters and potential customers. I regularly plan my working diary to enable me to play or watch sport. As for other interests, I enjoy watching comedy, I particularly like Bill Hicks, an American comedian. As for TV, I rarely get enough time. I tend to spend evenings sorting out my domestic matters, cooking and cleaning, and planning my next working days. My involvement in sport has certainly helped me promote my business and above all has given me the opportunity to combine business and pleasure.There is never a dull life working in the sports turf industry, especially when you meet so many dedicated and interesting people. What more could I want out of life? I seem to be getting my cake and eating it.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80