SO THE WEED FACTOR IN THE CULTIVATION OF CORN. 



argued on the one hand that the crop should be so tilled as to induce 

 the germination of as many of the weed seeds as possible, with the 

 subsequent destruction of the seedlings. On the other hand it may- 

 be argued that under the conditions that existed on the nontilled 

 plats of these experiments, although a much smaller proportion of 

 weed seeds in the soil was induced to germinate, many of those that 

 remained ungerminated probably lost their viability and that as there 

 was a much smaller number of weeds on these plats than where the 

 land was tilled a correspondingly less number of weed seeds matured 

 to reseed the land in the latter part of the season after cultivation 

 stopped. 



It must be understood that there are no data to prove which of the 

 two opinions stated above is the correct one. It is impossible to say, 

 therefore, which of the two methods of treatment would be the less 

 conducive to weediness of the soil through a period of years during 

 which different crops were grown. The observations on these experi- 

 ments, however, seem to indicate that for the years in which the land 

 is in cultivated crops the work of weed control may be considerably 

 simplified by shallow rather than deep working of the soil. 



FAIRNESS OF THE TESTS. 



Although the weed growth seemed to be less on the uncultivated 

 plats than on the cultivated ones in some of the experiments, there 

 were others where the surface scrapings or hoeings were not sufficient 

 to keep down the weeds as thoroughly on the uncultivated plats as on 

 the cultivated ones. It is believed, therefore, that on an average for 

 all experiments the weed growth under the two kinds of treatment 

 was about the same in extent, but that if there was any difference in 

 this regard there were more weeds on the uncultivated than on the 

 cultivated plats — due to the fact that some of the cooperators did 

 not do as thorough work in keeping down weeds on the uncultivated 

 plats as on the cultivated ones. 



Another point which may have affected the fairness of the tests was 

 that where the experiments were located on sloping land there was a 

 tendency for rain water (especially at times of heavy rains) to run off 

 the uncultivated plats to the adjoining cultivated ones, where it was 

 caught and allowed to soak in the soil, on account of the rough and 

 absorptive condition of its surface, so that the cultivated plats 

 received more than their share of the precipitation. 



Altogether, if there was any advantage in favor of either of the sets 

 of plats it was on the side of the cultivated ones. 



257 



