An bamboo grower with 25 years experience tipped me to another way to tell the difference between Nuda and Bissetii: "The little shoots in the small plants look similar, BUT when taking the shoot like you are holding a pencil the nuda green culm sheaths will feel rough on the downward stroke between your fingers. P. bissetii will feel smooth. Then when the plant is able to send of a little bigger maturish shoot the bissetii will remain all greenish where the nuda will begin to get dark blotchy spots." Well, my plants feels smooth as silk both ways, so they must be bissetii. (Roger Sr., you were right, right on.) The grower was cool and sent me two replacement #1 Nudas air mail at his expense, and the culms in some cases are really blacker compared to the Bissetii. They're in the ground now after 23 days without any appreciable rain, and mostly 90 degree heat. How often do you water bamboo in a dust bowl...