 It is present in Europe and Asia as an introduced species, and it is known as a common weed in many regions.Its common names include great ragweed, Texan great ragweed, giant ragweed, tall ragweed, blood ragweed, perennial ragweed, horseweed, buffaloweed, and kinghead.This is an annual herb usually growing up to tall, but known to reach over in rich, moist soils.