Seasonality of Leaf Fall and Litter Production in Sal (Shorea Robusta Gaertn.F.) ANR Forest in Tarai East Forest Division, Haldwani

Sal (Shorea robusta), which is widely spread in both moist and dry forests in across the tropics, has been inconsistently described as either deciduous, semi-deciduous or evergreen species. To assess this contradiction, a quantitative record of the sal leaf dynamics (via monthly counts on tagged leaf falls and twigs) was made in different ANR sites of the Tarai East Forest Division, Haldwani. By using sample plots, the annual leaf fall data was collected and analyzed. The annual litter production (leaf fall & twigs) was maximum (8003.38 kg ha–1 yr –1) recorded in Surai (Jhankiya) followed by Kishanpur (Horai) 5434.52 kg ha–1 yr –1; Jaulasal (Bera) 5291.03 kg ha–1 yr –1 and its seasonality (month of leaf-fall) was 12-16% in ( Ist February – 1stMarch), 22.0-30.0% in (Ist March – Ist April) and 40.0-43.0% in (Ist April to Ist May) in Summer. In the species level the Shorea robusta (86-90%) has maximum leaf fall coverage in ground, followed by Largestoennia sp. (6.0-10.0%), Terminalia sp. (2.0-6.0%), Schleichera oleides (0-2.0%) and Bauhinia sp. (0-2.0%) was observed. Throughout in March – April ( the transitio-nal month for the leafing pheno-phase); the two phenological variation were observed and reflecting significant functional diversity in sal trees. These variation were as follows; variation (a). Leaf fall completed and new leaf flushing begins; variation (b). Leaf fall and new leaf flush overlapping together. The presence of these variants are indicating that the most of individual of sal trees have semi-deciduous or evergreen characters in the division.