Which plant is associated with hematopoietic depression?

• A. bracken fern (pteridium)
• B. onions and garlic (allium)
• C. oak (quercus)
• D. daylily (hemerocallis)

Answer: (A)

Hematopoietic depression means the bone marrow is suppressed, leading to reduced production of red cells, white cells, and platelets. Bracken fern contains toxins such as ptaquiloside that damage rapidly dividing cells in the bone marrow, producing bone marrow suppression and often resulting in anemia, increased infection risk, and hemorrhage due to low platelet counts. That direct effect on the marrow makes it the plant most closely associated with hematopoietic depression.

Onions and garlic cause oxidative damage to red blood cells leading to hemolytic anemia rather than bone marrow suppression. Oak is more linked to renal (kidney) toxicity, and daylily toxicity in cats primarily causes kidney failure.