Two‐ and eight‐year‐oldPinus sylvestris, originating as controlled crossings from southern and northern Finland, were studied in order to determine their susceptibility to damage byMicrotus‐species. For characteristics that indicate climatic adaptedness (bud set, needle stage) there was a clinal change from north to south according to origin. These differences were not correlated with susceptibility to vole damage. Nor was the total phenol content of the saplings correlated with resistance to such damage. Between families, however, there were statistically significant differences in susceptibility to damage. Some families showed both rapid rate of growth and high resistance.