Alan, bissetii always follows Yellow Groove forms here by a week or two sometimes, but always noticeably later. I have bissetii just now shooting and other bamboos are approaching 3 meters tall. Might be my clone of it just shoots later but it also seems to be bigger than others.
Juvenile bamboo always seem to shoot early, as the grove matures they push back later each year.
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Brad Salmon, zone 5b/6 Southern Indiana
Winters -20 to -25C. Summers 30 to 35C , humid. 115 cm annual precipitation, frost free from May through early October. 259.3 meters elevation. Growing 150+ species.
http://www.needmorebamboo.com/