- Height: 1 block
- Typical crop, planted on farmland
- Time: Late Cretaceous
- Native biome(s): None (obtain from fossils)
- Dandelion Yellow (convert from the berries)
- Ink sacs (convert from the seeds)
- Poisonous to humans
- Poisonous to most herbivores
- Safe for hadrosaurs (such as Parasaurolophus)
Native to North America, Rhamnus salicifolius is an extinct species of buckthorn that grew at the very end of the Late Cretaceous, around 66 million years ago. Its fossils have been found at the famous Hell Creek Formation.
Buckthorns (genus Rhamnus) are still around today in the temperate and subtropical regions of North America, east Asia, Africa, and South America. They produce distinctive berries (usually either red or black in colour). However, these berries are somewhat poisonous, and are generally unsafe for consumption by humans. Instead, the berries are often used to make yellow dyes, and the seeds are used to make lubricating oils, printing ink, and soap.
Commonly referred to by park staff as the "Cretaceous buckthorn", R. salicifolius is somewhat poisonous, just like many of its modern descendants. The effects of eating them are generally mild, but can be rather annoying due to their purgative properties. Some dinosaurs however, such as hadrosaurs, appear to produce a kind of natural antidote to the buckthorn's poison in their digestive systems, meaning they can generally eat the berries without side effects.
Despite being inedible to humans and most non-hadrosaurian dinosaurs, the Cretaceous buckthorn has its uses. Its berries are a great source of yellow dye, and its seeds can be made into ink.