He believed that the symptoms were caused by freshly cut hay, so the condition was called hay fever.
ولأنه عزا اسباب هذه الاعراض الى العشب اليابس ،‏ او الكلإ ،‏ المقطوع حديثا ،‏ دُعيت الحالة حمى الكلإ .‏