PREFACE 
r 
AS in the case of a previous volume, Common Weeds of the Farm 
*- and Garden, the preparation of this handbook was undertaken 
because of the great lack of readily available and reliable information 
on the subject in English scientific literature. Many of the facts were 
known to a few interested persons, but many others were so scattered 
here and there in technical reports and journals that they were scarcely 
known even to expert chemists and botanists. The bringing of this 
information together in some sort of order has involved considerable 
labour extending over several years, but if the volume be found helpful 
to those for whose use it has been prepared I shall feel more than 
gratified. 
That the subject is of importance is fully realised by farmers and 
veterinary surgeons alike, for the annual loss of stock due to poisonous 
plants, though not ascertainable, is undoubtedly considerable. It was 
felt that notes on mechanical injury caused by plants and on the 
influence of plants on milk might usefully be included, as in some 
degree related to poisoning; this has therefore been done. On the 
other hand, a number of cultivated plants (e.g. Rhus, Wistaria) which 
are poisonous have not been included because exotic and hardly likely 
to be eaten by stock. Fungi generally also find no place in the volume, 
as they are sufficiently extensive to deserve a volume to themselves, 
and are far less readily identified than flowering plants. 
The dividing line between plants which are actually poisonous 
and those which are only suspected is far from clear, but a division 
was considered desirable for the convenience of the reader, and an 
endeavour has been made to give a sound but brief statement as to 
the present information on plants poisonous to live stock in the United 
Kingdom, with symptoms, toxic principles, and a list of the more 
important references to the bibliography in relation to each plant 
included in Chapters n to vi (the numbers corresponding with the 
numbers in the Bibliography). 
Regarding symptoms it is to be regretted that in many cases they 
appear to be the result of injections of the toxic extracts, and not 
observations made after natural poisoning by ingestion of the plants. 
