Abstract Relationships of crown size, bole size, competition, and growth to sap-volume yield, sap-sugar concentration, and total sugar yield were examined in sugar maple trees ( Acer saccharum Marsh.), using stepwise regression and covariance analyses. Observations were made on 60 trees located in each of three sugarbushes in Vermont. Derived equations were not precise enough for prediction of yields; relation among variables differed among sugarbushes and years. Physical characteristics of individual trees are good criteria for judging potential yield in a broad sense, but past importance placed on them was not justified. Forest Sci. 19:175-179.