Burning Recommendations 73

Burning Recommendations for 1974
Project Leader and Principal UC Investigators G.E. Miller, J.R. Goss, J.F. Williams, J.F. Thompson, project leaders, UC Davis and UCCE, Combustive Disposal of Rice Straw and Stubble (RM8) C. Page I. Akpan D. Fischer M. Engstrom B. Boynton	For minimum smoke in burning rice straw . . . pay strict attention to the following recommendations derived from latest University of California research. You will get definite and large improvements if you: Minimize straw moisture by spreading straw behind the harvester. Let dry for 2-3 days on standing stubble or up to 10 days or more on minimum-height stubble. Test representative samples of straw with a moisture meter to be sure moisture is 10-12% or less; or hand-test for audible crackling when straw is sharply bent. Bum when air relative humidity is 50% or less. Ask your local air pollution control officer for burning hours in your area. Use backfires, sidefires, and into-the-wind striplighting where practical. Employ headfires or peripheral fires with caution when residue is very dry and other techniques are inadequate. Studies now confirm that backfires do indeed produce less smoke: about half the particulate emission of headfires. Emissions are similarly reduced with sidefires and into-the-wind striplighting, techniques that help overcome the slow travel of a line backfire. Into-the-wind striplighting is an innovation that combines the low emissions of backfiring (or sidefiring) with nearly the speed of headfiring. To use this principle, the downwind side(s) of the field are lit as backfires, and then line fires are lit at intervals of 400-600 feet heading straight into the wind, lighting from the backfire side toward the upwind side of the field. The fire then becomes a series of arrow-shaped fires heading into the wind. (If the wind changes, some headfiring will result, amounting to no more than 20-30% unless the change is large and lasting.) A caution: We've had no problems yet - BUT a fire lighter might become incapacitated in the middle of the field. So a buddy system is advisable, with lighters working in pairs near each other, to watch for emergencies and give aid. (The fire moves at only about 3 feet per minute, so it will not normally be a hazard.) (RM8)

Burning Recommendations
for 1974

Project Leader and Principal UC Investigators

G.E. Miller, J.R. Goss, J.F. Williams, J.F. Thompson, project leaders, UC Davis and UCCE, Combustive Disposal of Rice Straw and Stubble (RM8)

C. Page

I. Akpan

D. Fischer

M. Engstrom

B. Boynton

For minimum smoke in burning rice straw . . . pay strict attention to the following recommendations derived from latest University of California research.

You will get definite and large improvements if you:

Minimize straw moisture by spreading straw behind the harvester.
Let dry for 2-3 days on standing stubble or up to 10 days or more on minimum-height stubble.
Test representative samples of straw with a moisture meter to be sure moisture is 10-12% or less; or hand-test for audible crackling when straw is sharply bent.
Bum when air relative humidity is 50% or less. Ask your local air pollution control officer for burning hours in your area.
Use backfires, sidefires, and into-the-wind striplighting where practical.
Employ headfires or peripheral fires with caution when residue is very dry and other techniques are inadequate.

Studies now confirm that backfires do indeed produce less smoke: about half the particulate emission of headfires. Emissions are similarly reduced with sidefires and into-the-wind striplighting, techniques that help overcome the slow travel of a line backfire.

Into-the-wind striplighting is an innovation that combines the low emissions of backfiring (or sidefiring) with nearly the speed of headfiring. To use this principle, the downwind side(s) of the field are lit as backfires, and then line fires are lit at intervals of 400-600 feet heading straight into the wind, lighting from the backfire side toward the upwind side of the field. The fire then becomes a series of arrow-shaped fires heading into the wind. (If the wind changes, some headfiring will result, amounting to no more than 20-30% unless the change is large and lasting.)

A caution: We've had no problems yet - BUT a fire lighter might become incapacitated in the middle of the field. So a buddy system is advisable, with lighters working in pairs near each other, to watch for emergencies and give aid. (The fire moves at only about 3 feet per minute, so it will not normally be a hazard.) (RM8)