104 PLAXT LIFE ON THE FARM. 



ovina> Agrostis vulgaris, Avena elatior, Holcus lanatus 

 and Poa pratensis, are noted to have been predominant, 

 Poa trivialis, on the contrary, being practically banished. 

 The two first-named plants owe their predominance not 

 exclusively to the manure, for they thrive luxuriantly 

 under many other conditions. A similar remark applies 

 to Rumex Acetosa. On those plots where the quantity 

 of ammonia salts was doubled, Dactylis glomerata for 

 some years was in enormous preponderance, Agrostis vul- 

 garis, Holcus lanatus, Alopecurus pratensis and Avena 

 elatior have been also in large quantities. Briza media. 

 Cynosurus cristatus, Lolium perenne, Bromus mollis, all 

 poor grasses, except Lolium, have been discouraged by 

 the ammonia. Poa trivialis also has greatly diminished 

 in proportion to the quantity of P. pratensis. 



Among the miscellaneous plants, Ranunculacese, like 

 the Leguminosse, have been practically banished. Um- 

 belliferae have been almost expelled, Composite largely 

 diminished, Labiates greatly reduced ; Plantago lanceo- 

 lata is unrepresented, and even Rumex Acetosa consider- 

 ably diminished. As these or corresponding effects are 

 generally observed where ammonia forms part of the ma- 

 nure employed, and as they are enhanced when the 

 quantity is increased (though not in direct proportion), 

 it would seem that ammonia must be actually prejudicial 

 to some plants. It is probable, however, that the dimin- 

 ished proportion of these plants is more often due to the 

 increased luxuriance of the stronger-growing grasses than 

 to the directly prejudicial effects of the manures on the 

 other plants. 



It is generally observed, that on the ammonia plots 

 the plants show a great tendency to form leaves, and 

 when mineral manures are added, the period of ripening 

 is hastened, and its degree enhanced. A combination of 

 mineral and ammonia salts, where the latter are not in 

 excessive proportion, is beneficial to almost all crops, as 



