Status Updates From The Great Compassion: Buddh...

In discussing who is and is not sentient ie worthy, the author excludes plants declaratively and then hedges: "Worms and insects are certainly above it. Microorganisms are probably below it. But wherever scientific investigation ultimately places it, the line is certainly far lower than most of us have been willing to consider." Since 2004, there's more information about plants: communication and sentience.