Needle mass, length, and nitrogen concentration, and their relation to site index were studied for lodgepole pine(Pinus contortaDougl.) and Scots pine(Pinus sylvestrisL.). Needles were collected at 53 locations throughout Sweden where the two species, of the same age, were growing on adjacent, comparable sites. Sampling was done throughout the growing season, with a pause during the period of most active growth. Needles of lodgepole pine had a higher mass, were longer, and had a lower nitrogen concentration than those of Scots pine. Site index was positively correlated to needle length and weight for both species, and to nitrogen concentration for lodgepole pine. For the characteristics studied, the relative differences between needles of the two species decreased with increasing site index.