Rainbow Cacti

The Rainbow Cacti [sic] is a block added by Thaumic Bases. When it is harvested and is not the last block it will drop almost all dyes (with the exception of black, white, and blue dyes), with Cactus Green dropping more frequently than others; any Rainbow Cacti blocks above the harvested one will drop intact. Like regular Cacti it grows 3 blocks high except that coming into contact with it will not inflict damage or destroy items.