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of the unevitable June hug are made of heaps of scattered, moist bark which 

 heats itself. The June bugs lay their eggs in these heaps which later, with 

 a part of the underlying earth, are put in a wagon and worked up with peat, 

 or lignite, ashes, lime, plaster and organic refuse to a compost pile, which, 

 after a year or two, kills the grubs. 



Harrowing. 



Harrowing is a process which should find mention here. Anderegg' 

 has [>ublished very noteworthy results of harrowing meadows. A meadow 

 of uniform soil composition and mould was divided into four equally large 

 lots. These yielded, — 



(i). Unharrowed and unfertilized }^yy kg. hay 



(2). Unharrowed but fertilized '"^33 kg. hay 



(3). Harrowed but unfertilized 770 kg. hay 



(4). Harrowed and fertilized 1563 kg. hay 



Harrowing winter sown grains not only re-opens the encrusted soil, but 

 also increase considerably the formation of young shoots. Director Con- 

 radi-, however, justly points out the fact that the harrow is usuable only if 

 the crust is not too thick and the soil not too binding. Also, if an encrusta- 

 tion in spring may be foreseen, the seed must be more thickly sown since 

 harrowing destroys plants and the sand is thinned. For that reason har- 

 rowing is very useful occasionally in thinning the plants. The increased 

 standing room for the plants left in place gives a greater supply of light to 

 the basal nodes and starts the lateral shoots into a rapid growth and pre- 

 vents their too rapid lignification when these buds obtain moisture from the 

 earth heaped up by the harrowing, li the '"arth is not pulverized sufficiently 

 by the harrow, the roller, and preferably a wheel roller, must be used in ad- 

 dition. In the majority of cases the roller will have to follow the harrow, 

 because binding soils are not made absolutely fine by the harrow, and also 

 because it is desirable that the earth torn away from the base of the plants 

 may be pressed back again. The best time for harrowing depends on the 

 development of the plant and the water content of the soil. If the plants 

 have grown too far or continuous dry weather prevails, the harrowing 

 should be omitted or, in the latter case, should never be carried out without 

 a subsquent rolling. 



A few words also might be pertinent here as to the significance of stones 

 in the soil. In this connection. W'ollny's'' experiments have shown that 

 with a high, constant air temperature (during the warmer seasons) soil 

 covered with stones and mixed with them is slightly warmer than is that 

 free from stones. \Vith a falling temperature comes the reverse. During 

 the daily minimum soil temperature, soil containing stones is for the most 



1 Illustr. landw. Verein-sblatt, 1880; No. 8; cit. in Hicdcrm. Centralbl. f. Agrik.- 

 Chcmie. 1880. p. 693. 



- From "Der Praktische Landwirt" in Fiihling's landw. Zeit., 1880, p. 151. 

 3 Wollny, Fuhling's landw. Zeit. 1880, p. 314. 



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