Tree and shrub litter production was measured over 2 years in 12 jack pine (Pinusbanksiana Lamb.) and 2 white spruce (Piceaglauca (Moench) Voss) dominated stands located in the Hondo – Slave Lake and Athabasca Oil Sands areas of north central and northeastern Alberta. Annual and daily production rates were calculated for foliage (by species), male cones, and structural material (bark, twigs). Annual litter fall weights were typical of those measured in other boreal regions and were correlated with stand basal area. Seasonal patterns in daily production rates suggested that three classes of control factors were involved in determining litter fall rates within a stand. Random factors, such as weather, and chronic factors, such as insect or disease activity, contolled foliage and structural litter through most of the year. Predictable seasonal factors relating to plant physiological state controlled autumn foliage litter fall in deciduous and most coniferous species and production of male cone litter in early summer.