Determines fine root turnover of Norway spruce and understorey in two climatically contrasting forests in Finland.

Shows that spruce fine root live longer at the northern site than at the southern site.

Calculates the ratio of below- and aboveground litter production in these and four additional sites.

Relates the ratio of below- and aboveground litter production to site fertility.

Shows that nutrient-poor sites produce relatively more litter belowground than aboveground.