|"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.
Red oak (binomial name Quercus rubra) also known as northern red oak or champion oak is an oak in the red oak group (Quercus section Lobatae).
Garrick Ollivander noted: "You will often hear the ignorant say that red oak is an infallible sign of its owner’s hot temper. In fact, the true match for a red oak wand is possessed of unusually fast reactions, making it a perfect duelling wand. Less common than English oak, I have found that its ideal master is light of touch, quick-witted and adaptable, often the creator of distinctive, trademark spells, and a good man or woman to have beside one in a fight. Red oak wands are, in my opinion, among the most handsome."