21 November 1997

Temperature key to balanced beet clamp

TEMPERATURE monitors are helping one Lincs beet grower strike the right balance between frost-free clamps and minimal sugar loss from overheating.

For the second year Tony Wright, farms manager at LCAH Farms, a subsidiary of De Montfort University, Caythorpe, Lincoln, is using a temperature monitoring system supplied by British Crop Development.

Last season he stored beet to the end of February with the clamp temperature never rising above 8.5C or dipping below 6C.

Monitor beneficial

"The monitor was beneficial and we shall use it again. And after the beet has gone we plan to use it to monitor the temperature at the bottom of corn bins, too."

University research shows that at 9C a sugar beet loses more than a third of its sugar content during 15 weeks of storage, says Peter Taylor of Lincoln-based British Crop Dev-elopment. By contrast a sugar beet at 5C loses just a sixth of its sugar.

"That four degree difference is clearly critical, so growers should aim for a practical clamp temperature of 4-6C."

Monitoring the internal temperature of a clamp helps avoid overheating in two ways. Most obviously it indicates when frost protection coverings should be removed. But it also shows when best use can be made of passive ventilation using cool winter air.

Keen to continually improve his clamping technique, Mr Wright replaced one of the three concrete sides of his clamp with Hesston big bales on top of pallets this year. That will allow cool air into the clamp, with small bales in front of the pallets to block the air flow when it is not needed.

The Hesston clamp side also eases access, allowing the warmest parts of the clamp to be delivered first.

"Consider your clamp as a number of temperature monitored sections," urges Mr Taylor. "Deliver the warmest section first, as this is losing the most sugar a day. Growers with a number of clamps can deliver the warmest clamp first or start from the warmest end."

Making a good job of beet harvesting from the outset is also important, stresses Mr Wright. "Our contractor uses a three-row machines and we take care at the clamp site, using dumper trailers and handling the beet as gently as possible with the loader. A perfectly level top to the clamp is crucial." &#42

Peter Taylor (left) and Tony Wright will be monitoring beet temperatures carefully and using cool air ventilation to minimise sugar losses this season.

BEET CLAMPING

&#8226 Avoid overheating.

&#8226 Temperature monitors show when to allow cool air into the clamp and when to remove frost protection covers.

&#8226 Straw sides on pallets allow cool air in and more flexible emptying.

&#8226 Monitors cost from £165.