XXX 



PLANT ALIENS 



" The noisome weeds, which, without profit, suck 

 The soil's fertility from wholesome flowers." 



SHAKESPEARE. 



T)RECISELY what constitutes an This species is the Canadian fleabane, 

 alien plant is an unsettled ques- or horse-weed, which came over, so 

 tion. Some botanists do not consider runs the story, in the seventeenth 

 a plant necessarily indigenous even if century, a solitary seed having acci- 

 found in deposits of the Glacial Age, dentally been packed along with a 

 much less in those of the Palaeolithic stuffed bird. Of no great mischief, 

 or Neolithic period. For our present the horse-weed has nevertheless dis- 

 purpose, let a statute of limitations tributed itself all over the kingdom, 

 be passed, so that we may call a plant The hamlets near the station have 

 native if its pedigree can be traced suffered invasion from another Corn- 

 back to pre-Roman days. posite, the galinsoga, a wanderer from 

 Starting from London for a long Peru ; this species has within fifty years 

 day's ramble, we will first take a rail- contrived largely to oust from fields 

 way journey of about a dozen miles, and gardens the ubiquitous ground- 

 Our object is to scrutinize closely the sel. Without leaving the district, one 

 antecedents of any suspicious plants, may notice the small-flowered balsam, 

 not excluding too rigidly, but paying or spotted touch-me-not, a harmless 

 no heed to the havoc which must be little intruder, which perhaps arrived 

 wrought with the " London catalogue." as a stowaway with garden seeds. 

 Many casual plants, such as foreign tre- As we saunter along by the hedge- 

 foils and pepperworts, may be looked for rows of a village built on the London 

 on the railway banks ; obviously these Clay, we are reminded that the rugged 

 cannot be examined. In the station elm has been called into court. The 

 yard, however, there is a miniature accusers state that the common elm 

 forest of little feather-fruited strangers never the indictment is as sweeping 

 which might carelessly be passed over as it is hazardous sets its fruit, hence 

 as groundsels. Truly, the flower be- it is not native. Against the edible 

 longs to the Composite order, but the chestnut the charge is more serious, 

 pappi of the head are white, not yellow, though the tree seems to be as old as 



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