Seasonal Variation of Terpenoid Constituents in Natural Populations Ofjuniperus Pinchotii Sudw

Foliage samples were taken from sixteen trees in eight natural populations of Juniper us pinchotii Sudw. in July and again in January to determine if seasonal variations occur in the volatile terpenoids and if the summer or winter collections would be more variable. Gas/liquid chromatographic analysis revealed that significant differences do occur from summer to winter in the relative composition of the terpenoids. The summer collections were more variable than the winter collections which indicates the desirability of winter sampling when practical.