Kalmar "perennial ragweed" tana nufin wani nau'in shuka da aka sani a kimiyance kamar Ambrosia perennials. Wani nau'i ne na ragweed wanda ke girma a matsayin tsire-tsire na shekara-shekara, ma'ana yana rayuwa fiye da shekaru biyu kuma yana iya girma a kowace shekara. Ragweed Perennial shine a
