Scientific Agriculture. 



38 



[Jan. 1908 



greater for a day or so than from the other, but this evaporation takes place chiefly 

 from the loosened portion, and hence in a very short time, provided no rain falls, 

 this layer becomes dry and acts as a blanket to protect the soil below, diminishing, 

 the evaporation in one test we made by 62*5 per cent. Hence it is a matter of vital 

 importance that the soil should be cultivated at the earliest possible moment. A 

 delay of one week in this operation after the soil is fit will rob the soil of from one 

 to two inches of water, an amount sufficient to tide the crop over the critical period 

 of a drought. Deep cultivation is not advisable, for all of the loosened layer dries 

 out in time of dry weather, and since the deep blanket is little, if any, more 

 effective than the thinner one, the extra loss from the thicker blanket itself is not 

 atoned for by greater saving of water in lower layers, and is therefore a net loss 

 to the plant. 



With cereals the conservation of moisture by cultivation may be continued 

 until the grain is nicely up. If a rain has come, packing down the soil and destroying 

 the loose blanket and thus setting up rapid evaporation again, it is good practice to 

 run over the crop with a light harrow and restore the blanket. The saving in 

 moisture will more than atone for any injury the harrow may do the young 

 plants. With roots and other hoe-crops conservation of moisture may be continued 

 throughout the whole season. Theoretically, they should be scuffled or cultivated 

 after every heavy rain. This frequent working may not be always possible, but it 

 should be followed as closely as practicable. 



In humid sections, where the autumn rain is usually sufficient to saturate the 

 soil, after-harvest conservation of moisture is not essential, and the customary 

 ganging serves to sprout the weed seeds, and also, together with the fall plowing, to 

 put the soil in condition to retain enough water for the ensuing crop. But in sub- 

 humid or semi-arid regions the tillage right after harvest is essential for the purpose 

 of conserving moisture, as well as for the reasons already given. 



Before leaving the question of soil moisture, I should like to refer briefly to 

 the work in drainage that is being done by the department of Physics. Throughout 

 the Province there are thousands of acres non-productive, or under-productive, at 

 least, which, if drained, would be the very best of land. People are realizing this more 

 and more, and drainage operations are being more generally undertaken than here- 

 tofore. But in many cases men are hesitating because they are not sure as to the 

 best methods of going about it, whether they have fall enough, the best course for 

 the drains, etc The department of Physics is endeavouring to help these men. 

 Auyone having such difficulties may have the assistance of a man from our depart- 

 ment to take the levels of his land, determine the falls, locate the drains, give him a 

 working plan of his farm or field, and advise him generally as to the best methods 

 of operation. The condition upon which this service is rendered is that those 

 wishing work done pay the railway fare, etc., of the person sent by us. When the 

 applicant lives a considerable distance from Guelph, he sometimes clubs together 

 with one or two of his neighbours who have work to be done, each paying a share of 

 the expenses. 



We have done a great deal of this woi'k during the past season, and the men 

 for whom we have done it expiess themselves very strongly on the benefits derived. 

 I mention it here because of its connection with the subject in hand, and also in the 

 hope of making the scheme more widely known. For the initiation of the plan, I 

 wish to give due credit to Professor Reynolds, my predecessor, in the department. 



Another important soil factor is proper temperature. There is a certain 

 temperature at which each kind of seed germinates best. Of the more common 

 cereals, wheat has the lowest germinating temperature at about 70°, barely, oats 

 and peas probably in the order named, at about 80°. This may throw some light 



