Scheduling is best way to keep water on tap
Using water more efficiently
was the theme at this
years Water for Farming
event in Peterborough.
Edward Long reports
ONLY about 1 in 10 farmers who irrigate use any form of scheduling system to target water to where it is most needed at the most appropriate time.
But the need for some form of water management is increasing as it becomes more costly, supplies dry up, and integrated crop management protocols are implemented. That is the opinion of ADAS Huntingdon-based water specialist Colin Smith.
A trial at ADAS Gleadthorpe in Nottinghamshire between 1992 and 1995 showed the benefits of scheduling. Potatoes irrigated at a fixed seven-day interval received 308mm and yielded 49.8t/ha. Assuming a price of £80/t and £3.50/mm/ha for the water, the margin over the unirrigated was £1074/ha.
Where the interval was adjusted to allow for rainfall with a one-day delay for every 5mm of "free" water only 242mm of irrigation was needed. The crop yielded slightly less at 49.5t/ha but the margin was better at £1281/ha.
A fully scheduled approach brought an even greater benefit. The crop given 192mm of water yielded 49.2t/ha and a margin of £1432/ha.
"But the real advantage comes in a dry season when growers are short of water, as most who irrigate are. Then scheduling allows it to be better targeted. If it is in very short supply yield will be lost, but scheduling will help to reduce losses," Mr Smith says.
Too few growers schedule their irrigation and lose up to £350/ha as a result, says Colin Smith.
• Only 1 in 10 growers use irrigation scheduling.
• Scheduling can boost profit by over £350/ha.
• Full better than partial irrigation.
• Reconsider water supply.