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_Ephedra_ & some Mesozoic Paleobotany

Message text written by INTERNET:bettyc@flyinggoat.com
>You obviously aren't a gardener.  There's no getting rid of horsetails
ever.  Fire won't kill 'em either.  Once you have a single horsetail
frond show up, you have MANY horsetails for the rest of your life
popping up (heh heh) like weeds.  <

        Untrue!  I have a single, small horestail in my home and it's been
lonely ever since I got it.  (Of course, it _is_ a fossil one from the
Eocene Green River Formation...  ;-D  )

>The young plants can be cooked like asparagus and are recomended as a
'spring tonic' (I guess all that roughage)  
A chinese relative of the horsetail called Ma Huang/Ephedra is used to
treat asthma as it is a natural source of ephedrine.

        While the Mormon Tea plant (_Ephedra_) is indeed the original
source of the decongestant ephedrine, _Ephedra_ isn't close to horsetails,
phylogenetically speaking.  Horsetails (including the modern genus
_Equisetum_ and the fossil genera _Neocalamites_, _Calamites_, and others)
are all members of the plant group Sphenopsida, which, along with the
lycopods, are some of the oldest plant groups on the planet (although both
groups are depauperate in terms of diversity in the present compared to
their fossil diversities!)  _Ephedra_ was, last I heard, a member of a
tiny, possibly para- or even polyphyletic, group of plants that confuse
botanists because they have some angiosperm characters, but not enough to
make them angiosperms but are more than gymnosperms -- colloquially,
paleobotanists have referred to these plants (_Ephedra_, the bizarre South
African desert plant _Welwichia_, and a leafy, vine-like plant called
_Gnetum_) as Gnetales, or gnetaleans, which are frequently considered the
sister-taxon to angiosperms.  If there's a recent reference showing
_Ephedra_ to be closer to sphenopsids, I'd love to know about it!

           ____/_\,)                    ..  _   
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           /\  '                        ^__/>/\____\--------
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                     Jerry D. Harris
                 Fossil Preparation Lab
          New Mexico Museum of Natural History
                   1801 Mountain Rd NW
               Albuquerque  NM  87104-1375
                 Phone:  (505) 899-2809
                  Fax: ; (505) 841-2866