This is a new rule for my version of the reincarnation spell: If an elf casts induced reincarnation, he or she may choose whether to roll on the druidic table or the magic-user table. NPC elves have a 50% chance of choosing either table. (It just seemed to me that the druidic table was probably more appropriate to elves and should therefore be an option.)
This thought, along with the observation that magical spells are listed in Basic/Expert D&D as "magic-user and elf spells," led me to consider making separate magic-user and elvish spell lists in order to emphasize their differences. I could say that elves just use druidic spells, especially if I don't use druids in my game, or I could just include druidic spells as elvish specialty spells, just as magic-users who belong to guilds will have access to guild specialty spells. That might be the best approach. Then if I decide to use druids, they would still have greater access to druidic spells.
For now, the rule will be: Elves may choose one druidic spell per spell level of each spell level they are capable of casting. These spells are actually magical in nature, and must be memorized in the same manner as their other spells.