Experiments with different Top-dressings upon Wheat. 5 



progress of the experimental plots, it is a sore trial for the ex- 

 perimentalist to have to report, " Results vitiated by the ravages 

 of the black caterpillar." Indeed any one who is not prepared 

 to meet with more disappointment than success, will be wise 

 to desist from trying his hand at field experiments. I am led to 

 make this remark because only the season before last my experi- 

 ments upon swedes were entirely spoiled by the black grub. 

 Again last season I instituted an extensive series of experiments 

 with top-dressings upon barley, and, after having incurred con- 

 siderable expense and taken much trouble, all that I can report 

 is, u Results vitiated by the ravages of the wire-worm." 



My experiments upon the wheat-crop, I am happy to say, were 

 unusually successful. No hail, drought, mildew, or rust, inter- 

 fered with the success of the trials. I was fortunate enough to 

 find a good and most equal plant on a perfectly level and uniform 

 field of the Royal Agricultural College farm. The day on which 

 the top-dressings were applied was calm and cloudy ; a moderate 

 rain that fell on the next day washed the various manures into 

 the soil, and secured at once their uniform distribution. The 

 season, on the whole, was favourable to wheat, the weather at 

 harvest time was unusually splendid, and on none of the experi- 

 mental plots was the crop laid in the slightest degree. 



The field on which the experiments were tried is perfectly level, 

 and throughout of uniform depth. Its extent is about 20 acres ; 

 and last season the whole was in wheat after seeds ; 2 acres 

 covered with a very equal plant were measured out for the expe- 

 riments and carefully divided into 8 parts of equal length and 

 breadth. Each experimental plot thus occupied the space of 

 J- acre. The 2 acres under experiment were surrounded by a 

 considerable breadth of the general wheat-crop, except on one 

 side. Although the headland, and a portion of the rest of the 

 land, separated on that side the experimental plots from the ad- 

 joining hedge, it was considered prudent to reject the J acre next 

 to the hedge. Seven plots of J acre each in extent thus were left. 

 These plots were manured as follows : 



To Plot I. was applied 70 Ibs. of Peruvian guano ; or at the rate of 2 cwt. 



per acre. 

 II. 49 Ibs. of nitrate of soda; or at the rate of If cwt. 



per acre. 

 III. 45 Ibs. of nitrate of soda and 42 Ibs. of common salt ; 



or at the rate of 1^ cwt. of salt and 180 Ibs. of 



nitrate of soda per acre. 

 IV. 1 cwt. of Proctor's wheat manure ; or at the rate of 



4 cwt. per acre. 

 ,, V. 1 cwt. of the same wheat manure ; or at the rate of 



6 cwt. per acre. 

 Plot VI. was left unmanured. 



To riot VII. was applied about 1 ton of chalk-marl ; or at the rate of about 

 4 tons per acre. 



