The data set presented here represents part of a study that examined the ecological consequences of allochthonous litter deposition in tundra communities near Toolik Lake, Alaska. The study indicates that wintertime litter redistribution is an important mechanism of nutrient transfer across the Arctic landscape, increasing C and nutrient inputs to some portions of the landscape while decreasing their availability in other areas. Accumulation of windblown litter modifies the physical and chemical environment of patchy areas of the landscape and significantly alters some important biological processes such as respiration. Data are for control and litter plots and include net ecosystem CO2 exchange (umol m-2 s-1), photosynthesis (umol m-2 s-1), respiration (umol m-2 s-1), soil temperature at 5 cm (degrees C), and various dates for key phenological events (snow free, first green leaf visible, first flower petal visible, first flower open, first petal drop, last petal drop, first color change, and seed dispersal) for six important dry heath tundra plant species. The data span the time period of 19 June 1996 to 26 August 1998 UTC.