•The greatest loss of mass was recorded in fresh habitats.•The high moisture content slowed the wood decay process in the boggy habitats.•FWD can be a useful source of nutrients that can be released in to the soil.•Wood species and habitat moisture had the greatest influence on the wood properties. Deadwood is an essential element of forest ecosystems that is a source of nutrients and serves a very important role in the maintenance of biodiversity. Our study aimed to determine the decomposition rate of various species of deadwood while considering habitat conditions, especially moisture content. The study was carried out in the Czarna Rózga Reserve in central Poland. Research plots were designated in a habitat moisture gradient (fresh, wet, and boggy). Eleven wood species were included in the study in two forms (40-mm-long/40-mm-diameter cylinders and 50x50x22 mm cubes). Wood samples were placed directly on the soil surface. After 40 months, these were removed for laboratory analysis. A significant impact of habitat moisture on the decomposition processes of wood samples was observed. The greatest loss of mass (50%, on average) was recorded under fresh habitat conditions. A higher moisture content slowed down the wood decomposition process. In the boggy habitat, the weight loss was 34%, on average. Our research confirmed that fine woody debris may constitute a useful source of nutrients in forest ecosystems that can be released over a short period of time.