|"Is this all real? Or has this been happening inside my head?"
The topic of this article is of a real-life subject that has been mentioned "in-universe" in a canon source. The Harry Potter Wiki is written from the perspective that all information presented in canon is true (e.g., Hogwarts really existed), and, as such, details contained in this article may differ from real world facts.
Prickly ash is capable of producing wand-quality wood, and is unrelated to the similarly named ash tree. Not much is know about the wandlore of prickly ash, but it was used by James Steward to create Chadwick Boot's wand.