Vietnam War: Forest Fire as a Military Weapon - Paperless Archives

SECRET
CLIMATE FF-HULB
FROSTFREE WINTER; HUMID, LONG BURN SEASON
All equatorial and frostfree tropical climates having high (+) values and high (-) values for the year, or at least
5 'B" months. Examples are:
Precipitation No. of Months Yearly Humidity Values
Location Pattern "H* ".D""B" +1 (1)
Balboa Hts., Panama Monsoon 8 2 3 +320 -32
Saigon, R. V. N. Monsoon 7 3 4 +273 -45
Malindi. Kenya Monsoon 4 4 6 +157 -58
Kadugli, Sudan Monsoon 5 5 7 +116 -79
Bombay. India Monsoon 4 6 8 +145 -89
Cook town, Aust. Monsoon 5 2 5 +206 -34
Leopoldville, Congo Monsoon 8 3 4 +202 -41
Vientiane. Laos Monsoon 6 3 5 +239 -42
Mandalay, Burma Monsoon 3 5 6 +130 -56
San Jose, Costa R. Monsoon 7 3 5 +270 -29
Temperature: Not limiting.
Precipitation: Plant growth is restricted during several dry months; causes leaf fall from most tree species, and
grasses become d.-y.
Major vegetation types Semi-evergreen, semi-deciduous, and deciduous tropical hardwood forests. Man-made
savana types and secondary forests are common.
Ground-story vegetation: Woody plants under forest canopy are tree seedlings, vines, and scattered shrubs.
Amount: Low to moderate in dry weight.
Moisture content: Drops during long dry season, but woody stems retain 100-120 percent of dry weight.
Litter layer: Only current leaf fall. Rapid chemical and biological breakdown during the wet season.
Total available fuel weight on a good burning day: 0.13 pounds per square foot.
Burn days: Dependable long burning season.
Desiccation needs. Must remove forest canopy and kill understory plants for successful burning. Use either foliar
sprays or an application of pellets to the soil.
Foliar sprays: Apply a defoliant spray at least 6 months ahead of planned burning date. w','ait at least 6 weeks
and apply a repeat spray on the exposed understory. On each date, apply the following mixture per acre:
8 lbs., a.e., of a 1:1 mix of 2,4-D and 2,4,5-T plus 2 lbs., a.e., of picloram ester, both herbicides
combined in diesel oil to make a total mixture of 5 gallons.
SECRET B.7