Blackthorn is a Tier 2 plant from Industrial Craft 2 (Tiers range from 1-8). It can only be obtained by Cross Breeding. It is a convenient way to obtain Ink Sacs should you not wish to go squid slaughtering.
It is a green stem based flower in its initial stages, identical to Roses, Dandelions, and all other flowers. Once mature, the flowers turn black.
Harvesting Blackthorn may yield an Ink Sac as well as a Blackthorn Seed Bag.
Blackthorn Growth Stages:
Retrieved from ‘http://tekkitwiki.com/w/index.php?title=Blackthorn&oldid=33917’