By Chip Deffaa
Updated April 19, 1996 at 04:00 AM EDT

Mercer Ellington, who assumed leadership of his father’s orchestra in 1974, died Feb. 8, 1996, a week after completing Only God Can Make a Tree. Reworked Duke Ellington classics (a semi-symphonic treatment of ”Caravan”) sit comfortably beside polished — if less emotional — new pieces, the most impressive of which is ”Osceola,” cowritten by Mercer’s teen son, Paul. Is a third generation of this dynasty emerging?