What causes the inflorescence structure we often h...

Most of the time it's genetics. But excessive heat during the flower cycle can cause it. Also too much CO2 can do the same. But it's mostly just genetic

I think 24/0 light schedule sometimes can cause it

WOW LOOK AT DAT!!!!! I FIND DAT WHEN I DO GET FOXTAILING IT IS FROM 1 OF 2 THINGS!!!!! WHEN I GROW OUTDOORS IT GETS VERY VERY HOT SOMETIMES IN FLOWER AND IT WILL DO DAT!!!! I HAVE ALSO SEEN SATIVA GENETICS DAT JUST FOXTAIL !!!! DER IS OTHER REASONS SUCH AS ROOT ZONE ISSUES AND OTHERS!!!!!!

Foxtailing is most commonly caused by stress on the top buds, especially from too high light intensity (lamp too close / PPFD too high), heat stress at the canopy, and overall excess radiant energy late in flower. These factors keep the plant hormonally in a “keep growing” mode instead of fully switching into ripening, so the floral meristem stays active and keeps stacking new calyxes on top of each other instead of finishing into one dense, compact cola.