NASTUS ELATUS
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        Slender culms with curved offsets at the base.  The lowest 2 or 3 sections of the culms are curved by as much as an inch on the mature plants.
        Hermine - "This is one of the Bamboos which wiggle around instead of making an effort to grow into mathematically perfect poles.  I give it high marks for this effort, & greatly enjoy seeing it growing in a tub or pot."