Phenolic acids were investigated in the needles of eight different pine populations, five of which were Pinus mugo, two -- P. silvestris and one a critical form described by Neumann as P. uliginosa. Twenty different phenolic acids were detected. Six were discovered in pine needles for the first time (salicylic acid, gentisic acid, γ-resorcylic acid, o-hydroxyphenylacetic acid, β-resorcylic acid, p-hydroxyphenylacetic acid). Each of the investigated taxons was shown to exhibit a characteristic spectrum of phenolic acids. The critical form from the locus classicus of Pinus uliginosa is of intermediate character.