1905] T RAN SEAU BOGS OF THE HURON RIVER VALLEY 427 



The effect of acidity upon cultivated plants has been investigated 

 in this country especially at the Rhode Island Agricultural Experiment 

 Station, under the direction of Professor H. J. WHEELER. The 

 experiments have been conducted upon "acid upland soils" (60), 

 and numerous reports have been published. These experiments 

 involved a great variety of plants and were carried on under natural 

 field conditions. The areas planted for comparison had their acidity 

 neutralized by the addition of CaCO 3 . The plants which were 

 favored by the liming include the orange quince, black Tartarian 

 cherry, Japan plum, Tilia americana, Ulmus americana, rhubarb, 

 Australian salt-bush, hemp, barley, oats, onions, Anthoxanthum 

 odoratum, Poa pratensis, Festuca ovina, Holcus lanatus, Festuca 

 elatior, Alopecurus pratensis, etc. Plants which^appear to be adapted 

 to the acid soil conditions include cranberry, blackberry, raspberry, 

 sheep sorrel, cow-pea, flax, corn, lupine, and soja bean. It would 

 appear, then, that the acidity of the soil solution is unfavorable for 

 the growth of some plants, and that it is a factor in the selection of 

 species for acid soil conditions. 



3. Food material. As to the presence of plant food materials in 

 the bog soil there is an agreement among all the analyses that have 

 been made. 5 The soils are unusually rich in nitrogenous materials, 

 some analyses showing three times as much as good upland soils. 

 But in the slow decay of the vegetable matter the nitrogen remains 

 bound up in organic compounds and is unavailable for the growing 

 plants. This is confirmed by experimental tests in which nitrogen 

 was directly applied, and by tests in which the conditions were 

 modified so as to permit the action of nitrifying bacteria. In such 

 cases crops were produced when the untreated humus produced 

 none. 



Under natural conditions the growth of the nitrifying bacteria 

 in bog soils is almost impossible. Three factors work against their 

 activity: (i) the acidity of the soil solution; (2) the lack of oxygen 

 due to high water content; (3) the lower temperature. It has been 

 found that the optimum temperature for these bacteria is 98 F. 

 (36.6 C.), and that their activity is very slight at 50 F. (10 C.) 



s Analyses of Wisconsin soils. Ann. Rept. Wis. Agric. Exper. Sta. 13: 304. 1896. 

 See also 27, p. 12; 23; 22, p. 276; 30; 48, p. 234; 12, p. 39; 14. 



