Senecio jacobaea, called tansy ragwort here, has been accidentaly
   introduced into several places in North America, including the Fraser
   Valley near Vancouver. Several years ago I worked for an entomologist
   attempting to introduce biological control insects (cinnabar moths
   didn't work because ground beetles cleaned up too well on their ground
   level pupae, but 2 species of specific seed eating flies are doing not a
   bad job since).
 
   The 93 edition Hive and honey bee (p 1195) lists S. jacobaea as
   poisonous to bees or brood, but doesn't give a reference for details.
 
   I've read that the alkaloids in tansy ragwort seeds (contaminating some
   grain crop, maybe Africa??) were enough to cause health problems in
   human consumers. (dairy cattle consuming tansy ragwort (in hay where
   they don't avoid it) have their liver harmed).
 
   Malcolm, there may be some information on alkaloid content of tansy
   ragwort honey available through your Agriculture ministry.
 
   Knapweed (Centaurea sp which has invaded about 100,000 acres of
   rangeland in B.C) sometimes is the source of large crops of a lovely
   looking golden honey which has not a bad flavour which in a few seconds
   turns to a very bitter taste which sticks in your mouth. Apparently the
   bitterness dissappears after a few months storage.  It isn't listed as
   one of the poisonous plants.
 
   cheers
 
 
   Kerry Clark, Apiculture Specialist
   B.C. Ministry of Agriculture
   1201 103 Ave
   Dawson Creek B.C.
        V1G 4J2  CANADA          Tel (604) 784-2225     fax (604) 784-2299
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