100 PLANT LIFE Otf THE FARM; 



and rich, deep blue-green foliage of the plants in the ad- 

 jacent ammonia plot is very striking. 



The effects of manure upon the struggle. When in 

 a long series of years the effects on the vegetation of a 

 particular plot are observed to be uniform in their nature, 

 if not in degree, the effects are obviously attributable to 

 the manure employed, and the fluctuations are as clearly 

 dependent on climatal variations. In endeavoring to 

 give an idea of the effect of different manures in influen- 

 cing the nature and fierceness of the struggle, it will be 

 convenient to allude first to those cases in which no 

 change has been made in the condition of manuring, 

 mentioning first those plots in which comparatively 

 simple manures are employed, and afterwards those in 

 which a more complex manure is employed. 



Mineral manures alone. One of the plots at Both- 

 amsted illustrates the effects of mineral manures consist- 

 ing of admixtures of various earthy and alkaline salts 

 used by themselves, without the admixture of nitroge- 

 nous substances. Speaking generally, it is there observed 

 that, while graminaceous herbage has, with much fluctu- 

 ation, slightly increased, the proportionate amount of 

 leguminous plants, as compared with grasses, has on the 

 whole been largely increased, although latterly it has 

 shown a tendency to decline. The large increase is 

 mainly due to Lathyrus pratensis, which prevails over 

 all its fellows. The grasses which hold their own best 

 are Festuca ovina, Agrostis vulgaris, and Holcus lana- 

 tus. Achillea Millefolium has increased considerably, 

 Conopodium denudatum and Rumex Acetosa, have usually 

 been abundant. This description of manure seems un- 

 favorable to most of the weeds of pasture-land other than 

 the above mentioned. The crop is generally moderate, 

 with an even and early ripening, and a marked tendency 



