Ghi chú nhận dạng và học tập

Lá dày bóng có ba gân chính phát từ gốc; hoa nhạt thành chùy nách lá, quả tím đen. Vỏ thuốc là lớp vỏ thân/cành dày cuộn ống/dải, thơm quế. Quế chi là cành non cùng loài, khác phần dùng. Quế Ceylon (Cinnamomum verum) khác C. cassia về loài/thành phần; không kết luận mẫu bằng mùi. AI không xác thực coumarin/chất lượng. Rou Gui and Gui Zhi are related but distinct materia: Rou Gui is bark from Cinnamomum cassia, while Gui Zhi is a twig material. A historical formula listing Gui Zhi does not authorize substitution with bark, whose composition and coumarin exposure differ. The evergreen tree’s three-veined leaves, panicles, and dark fruit help orient study; a strip of aromatic bark alone cannot identify species, tree age, or coumarin content. Culinary cassia products also vary by source and should not be equated with a medicinal bark lot. NCCIH’s caution about prolonged/high cassia exposure and liver effects is relevant to safety interpretation, not proof that every culinary serving causes injury. The tree takes years to establish and sources do not give a universal bark-harvest age. Do not strip a home tree or use bark as a daily “natural medicine.” In a formula note, transcribe whether the text specifies twig, bark, processed product, and exact source. This prevents a familiar cinnamon name from hiding a meaningful material substitution.