POISONOUS PLANTS.

Star (Christchurch), Issue 10300, 3 November 1911, Page 2

POISONOUS PLANTS.

A valuable article ou poisonous plants which are planted in our shrubberies appeared a little while ago in the London "Field." Only very few occupants of our gardens are known to be poisonous, although there may bo many others that at present aro unsuspected. Among trees and shrubs are the rhododendrons, aucubas, cherry laurels, laburnums, sumachs or rlius, hydrangea, buddleias, enonymuscs, brooms, and daphnes; whilst among exotoie herbaceous plants the hellobores, delphiniums, anemones, solanums, lupins, and colchiums are known to posses toxic properties. There are no doubt many more among those that are at present unsuspected. Dr Greshoff last year tested a largo number of plants cultivated in the Kew Gardens for their chemical composition, with a view to obtaining new data for pharmacology and toxicology. Ho discovered poisons where they were not even suspected to exist, for instance, in acacias, cassias, ceanothuses, choisya, deutzia, many clematises, arundo conspicua, gulega, lirodendron, philadelphus, pittosporum, olearia and platanus. There was found sufficient liydrocanic acid present in every London piano leaf to kill a London sparrow .

Other plants known to be more or less poisonous are the following;— Trees and shrubs -Ailanthus, anagyris, aristolochia, eoriaria, eoronelia, hedera, gym n i elaudus, jimiperus, juglaus, laurue, sassafras. Herbs—Amaryllis, cyclamen, l'ritillaria, gladiolus, lobelia, nieotiania, podophyllum, ruta, saponaria, thalietrurn, tulpia, veratrum, psoralea, spirea, syniphoricarpus, trollius and viburnum.

A noteworthy characteristic of theso vegetable poisons is that of being; more virulent.at one period of tho plant's development than at another. It may bo the young shoots that aro poisonous, and later, when they have matured, the poison is no longer present. Or the young shoots .may be innocuous and the old virulent. The toxic properties of many plants aro slow in their action, consequently they are not suspected when evidences of poisoning appear.

Fortunately the poisonous principle is often volatile, and almost, if not entirely, dissipated by drying, as. l'o r example, in tho case of the leaves and stems of buttercups, daffodils, and meadow saffron, which, although poisonous when green, nro quite harmless when they occur dry anion;;; hay. There is also safety in tho often disagreeable taste of most poisonous plants. The monkshood (aconite) is a deadly poison. Its roots have been dug up and served at the table instead of horseradish, and an instance is recorded where three persons died who had caton sauce with their heel' which had been made from monkshood instead of horseradish. Every part of this plant is deadly poisonous. The yew, box tree, elder, blackthorn, foxglove, caper spurge, ranunculus, scleratus or crowfoot, celandine, hemlock, black bryony, wood sorrel!. the bluebell or scilla, And many other British plants are more •>r less poisonous.