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I It should be thoroughly understood that these nitro-cultures are of use 

 for! legumes only, such as the clovers, beans, peas, and vetches, or, as they 

 are sometimes termed, the pod-bearing plants. We have had a number 

 of 'applications for nitro-culture for inoculating wheat, turnips, etc., but 

 these bacteria are of no use whatever for such crops. 



i^OIInoculation — and by inoculation we mean the treatment of the soil 

 or'seed with the nodule forming bacteria — is necessary when the land 

 has never before been seeded down to a leguminous crop, or if legumes 

 have grown in it without forming the characteristic nodules or tubercles, 

 which is proof that the nodule bacteria for that particular crop are not 

 present in the soil. In such cases as these the farmer may well resort to 

 inoculation. 



Inoculation is also desirable if a farmer wishes to grow a new kind of 

 legume on land even though it has previously grown excellent crops of a 

 different species of legume. Thus, although red clover may have been 

 successfully grown, with a large number of nodules on the roots, the bac- 

 teria from these nodules may not infect alfalfa or lucerne if it were planted 

 in the clover soil, and hence, inoculation with bacteria taken from the 

 afalfa nodules, would be desirable. So also, when introducing the culture 

 of vetches, of field beans, and soy beans, it would be necessary to treat the 

 seed with bacteria taken from these plants. In some cases, bacteria 

 derived from closely related species are mutually available, thus bacteria 

 from sweet clover (Melilotus) are capable of infecting afalfa. It seems 

 especially desirable in Ontario to inoculate the field bean and soy bean, as 

 experiments have shown that Ontario soils are not so generally infected 

 with the bacteria appropriate for these plants as for the other legumes, 

 and there is less possibility of their becoming inoculated from the bacteria 

 of closely related wild legumes, on account of the relative scarcity of the 

 latter plants. 



The employment of nitro-cultures is recommended also on soils which 

 produce a weak growth oi~ legumes even when nodules are present, the 

 more vigorous bacteria of the culture aiding the plant to fix more nitrogen and 

 in those cases where the leguminous crop is not producing the highest yield. 

 A word of warning is necessary with regard to failures in the use of 

 these nitro-cultures, and also with regard to their use as a remedy for lack 

 of. care in preparation and cultivation of the soil. No benefit may be 

 expected from the use of nitro-cultures if they are improperly prepared, the 

 directions for their use are clearly set forth, and should be strictly followed. 

 The farmer simply invites failure, if, for example, as some have done, he 

 disregards the directions and uses the culture on turnip seed, instead ot 

 forj the legume for which the culture was prepared. 



Failure of plants to form nodules, even when the seed is inoculated, 

 may result if : 



1 . The soil is too acid or too alkaline. Lime should be first applied 

 if the soil is too acid. 



2. If some fertilizer with a caustic action is brought into contact with 

 the treated seed. 



