i9i i.J The Destruction of Stinging Nettles. 987 



which information is frequently desired. Along the borders 

 of meadows and pastures, particularly shady spots, it is often 

 very troublesome, insidiously reaching further and further 

 from the boundary into the field if nothing be done to arrest 

 its progress. 



In arable land this nettle is best combated by digging out 

 and burning the rootstocks, following this up by thorough 

 and continued cultivation and hoeing to destroy any further 

 growth or any seedlings that may appear. 



In grass land small patches may be dug out by hand and 

 burnt, but this plan involves re-seeding. Another plan is to 

 cover the small patches with large sheets of strong tarred 

 paper, which should be pegged down and have a few heavy 

 stones placed on the top. The exclusion of light results in 

 the destruction of the herbage beneath. This plan also in- 

 volves re-seeding of the destroyed patches. 



In the case of either large or small areas this nettle may 

 be dealt with by regular cutting from the time the shoots 

 appear in the spring, cutting taking place each time the 

 fresh shoots attain 6 in. to 1 ft. in height. This plan, 

 thoroughly and regularly carried out, exhausts the reserves 

 of food material stored up in the rootstocks, and eventually 

 kills the weed. The eradication will be hastened by a dressing 

 of salt (say at the rate of 5 J lb. per rod, or on larger areas 

 6 cwt. per acre) when the nettles are first cut in spring. 



Experiments conducted in Germany* in 1909 with a view 

 to destroying nettles on large areas, showed that the young 

 shoots were destroyed in spring by spraying with a 15 per 

 cent, solution of kainit, applied with an ordinary charlock 

 sprayer. The shoots became black and died off, and the 

 grasses won the mastery, so that at the time of hay harvest 

 the area seemed quite free from the pest. Careful examina- 

 tion showed that the fresh delicate shoots from the root- 

 stock appeared sickly and but little grown, while the 

 rootstocks themselves were black and had begun to die. (As 

 about 35 per cent, of kainit consists of common salt, it is 

 probable that the effect of spraying with the solution of kainit 

 is largely due to the salt contained therein.) 



* Prak. Blatter fur Pflanzenbau u. Pflanzenschutz, Aug. 1910, p. 97. 



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