The variation of double bark thickness (DBT) along the bole was studied in three 24‐years‐old experimental plantations with provenances of lodgepole pine growing in central Sweden. DBT was found to vary with bole diameter over bark (DOB) and the height of the point of measurement relative to total tree height (RH). DBT at constant DOB and RH was influenced by locality and provenance. The variation in DBT differed in the most northern locality from the more southern localities: DBT relative to bole diameter was generally greater and there was larger variation within the bole in the northern locality. DBT relative to bole diameter was generally greater and there was larger variation within the bole in the northern locality. DBT decreased clinally with higher latitude and altitude of provenance. However, between provenances of south British Columbian origin no significant variation was observed.