▁out ▁the ▁plants ▁in ▁a ▁similar ▁way . ▁In ▁fact , ▁in ▁some ▁areas ▁the ▁plant ▁now ▁depends ▁on ▁periodic ▁human ▁disturb ance , ▁such ▁as ▁m ow ing , ▁to ▁clear ▁away ▁the ▁br ush ▁the ▁way ▁severe ▁natural ▁flo oding ▁once ▁did . ▁ ▁Population ▁sizes ▁vary ▁depending ▁on ▁the ▁amount ▁of ▁disturb ance , ▁such ▁as ▁flo oding , ▁occurr ing ▁in ▁the ▁area . ▁Pop ulations ▁have ▁been ▁noted ▁to ▁contain ▁anywhere ▁between ▁one ▁plant ▁and ▁one ▁million ▁plants ▁or ▁more , ▁and ▁some ▁populations ▁disappear ▁for ▁a ▁time . ▁Several ▁populations ▁of ▁the ▁plant ▁were ▁noted ▁to ▁increase ▁after ▁the ▁Great ▁Flo od ▁of ▁ 1 9 9 3 , ▁with ▁the ▁most ▁sever ely ▁sw amp ed ▁populations ▁growing ▁most . ▁Gen etic ▁analysis ▁reve als ▁the ▁species ▁is ▁gen et ically ▁diverse . ▁ ▁References ▁ ▁External ▁links ▁Bol ton ia ▁dec urr ens ▁Research ▁Station . ▁Southern ▁Illinois ▁University . ▁US DA ▁Pl ants ▁Profile ▁ ▁Category : A st ere ae ▁Category : Fl ora ▁of ▁Illinois ▁Category : Fl ora ▁of ▁Missouri <0x0A> </s> ▁Jon atan ▁Nord h ▁( born ▁ 2 7 ▁April ▁ 1 9 8 8 ) ▁is ▁a ▁Swedish ▁male ▁bad m inton ▁player . ▁ ▁Ach iev ements ▁ ▁B WF ▁International ▁Challenge / Series ▁Men ' s ▁Dou bles ▁ ▁M ixed ▁Dou bles ▁▁ ▁B WF ▁International ▁Challenge ▁tournament ▁ ▁B WF ▁International ▁Series ▁tournament ▁ ▁B WF ▁Future ▁Series ▁tournament ▁ ▁References ▁ ▁External ▁links