WEEDS— THEIR PECULIARITIES AND 



DISTRIBUTION 



By WINIFRED BRENCHLEY, D.Sc, F.L.S. 



Lawes Agricultural Trust, Rothamsted Experimental Station 



The wild plants of the countryside, sometimes collectively 

 designated " weeds," have always been of interest to the 

 community at large. Years ago, before the science of medicine 

 attained the position it now occupies, many remedies were 

 obtained from wild herbs and shrubs ; a few of these remedies 

 linger on to the present day, especially in out-of-the-way districts. 

 The old herbals and botanical works are full of accounts of 

 the preparation and uses of the various essences and decoctions. 

 Certain weeds still yield us some of our most valuable drugs, 

 for instance, Belladonna, which is prepared from the poisonous 

 Deadly Nightshade, whilst Henbane is obtained from the plant 

 so named. The popular names of plants were frequently 

 indicative of some special characteristic and habit, e.g. Bindweed, 

 which climbs by twining round other plants ; Irongrass or 

 Wirewecd {Polygonum aviculare), of which the stems are so 

 tough that they offer great resistance to the passage of agri- 

 cultural implements ; John-go-to-bed-at-noon {Tragopogon), so 

 named from its habit of closing at midday ; Poor Mans Weather- 

 Glass, which closes at the approach of rain. 



Nowadays, at least to the initiated, the term " weed " is far 

 more restricted in application, being applied only to those 

 plants which interfere in a greater or less degree with agri- 

 cultural and horticultural operations. 



At all times and under all systems of agriculture the intrusion 

 of weed plants into the crops has necessarily attracted attention. 

 To ensure the greatest measure of success in agricultural prac- 

 tice, it is of the first importance that the crops should be kept 

 clean ; as the presence of alien plants or weeds militates against 

 this end, a constant war has to be waged against the intruders. 

 So the more information of all kinds and from all sources that 

 can be gathered about such plants, the better the chance that the 



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