Text: 'Eleven experimental burns were conducted in the Kapuskasing District of the northern Clay Belt Region in Ontario for the period 1979-1983. The test fires, using strip headfires for ignition, were used to study the fire behavior in boreal mixedwood slash fuel complexes as it relates to the Canadian Forest Fire Weather Index System. Horizontal discontinuity of the fuel complex and poor drainage caused by a clay mineral soil makes fire spread difficult under low to moderate fire danger. Strong relationships were found for slash consumption and depth of burn with the Buildup Index of the Canadian Forest Fire Weather Index System. Weaker relationships were found for rate of spread and frontal fire intensity with wind speed and the Buildup Index. Because of poor drainage of the Clay Belt Region, forest managers are limited in site preparation methods that can be applied to harvested areas. Prescribed burning is one viable method of preparing the site. Guidelines were produced from the study to provide fire managers a better reference in prescribed burning these sites.'