'Fires are natural in boreal coniferous forest ecosystems, occuring every 100-200 years. Burning of the humus and forest vegetation (mainly spruce and understory) raises the pH of the humus of the podzolic soil and leads to new succession of the forest plant community. The prevention of forest fires may lead to lower base saturation and higher acidity of the podzolic soil. Tbe use of prescribed fire (burning of the humus after clear-cutting of Picea abies and seeding with Pinus sylvestris) was common in Finland until tbe eariy 60s. The method is coming into practice again since burning of thc humus counteracts soil acidification and mimics the effect of natural forest fire. Since 1989 we have been working on the effect of forest fire and prescribed burning on the humus microflora. Here, we present the results of the first and some results of second year after burning. A detailed publication of this project will follow elsewhere after the third year of study.'