326 EXPERIMENT STATION EECOED. 



influence of early and late spring plowing on corn production and the factors 

 influencing the supply of water in the soil are based on the work of M. Quiroga 

 (E. S. R., IG, p. 35(3). 



In considering the influence of weeds the experiments of Gates are quoted, 

 which show that plats on which maize was grown with rye, millet, and weeds 

 contained less moisture than maize plats kept cultivated, and that the yield of 

 ear maize was much greater where weeds were not allowed to start until June 

 27 instead of on June 14, although the difference in the percentage of moisture 

 in both series of plats was nearly the same. Determination of water-soluble 

 nitrogen in parts per million of dry soil here quoted indicate a great decrease in 

 the water-soluble nitrogen where the weeds grew and the land was not stirred, 

 as compared with plats which were stirred and no weeds allowed to grow. The 

 results of another test described in this connection show that plats scraped to 

 prevent the growth of weeds but not stirred yielded nearly as well as those that 

 were stirred thoroughly in removing the weeds, while the yield of grain was 

 greatly reduced on plats on which weeds were allowed to grow after the first 

 cultivation. The author considers the results as suggesting that the failure of 

 the maize to properly develop was due to other causes than lack of water or 

 available nitrogen. The influence of weeds as determined by Hosford is also 

 outlined. 



Plats varying from quite a sandy loam to a clay loam, with the soil moisture 

 ranging from 10.6 to 17.8 per cent, varied in yield of green maize fodder from 

 731 to 1,001 lbs. Other experiments quotetl sliow that the growth of millet 

 or weeds greatly checked the growth of maize, the yield of green substance where 

 millet was sown being oidy one-tenth and where weeds were allowed to grow 

 only one-fifth of that grown under ordinary cultivation, and that the total 

 green product produced on the weedy plats was much less than on those culti- 

 vated in the usual way. It is also pointed out that the percentage of moisture 

 was only slightly less on weedy than 'on cultivated plats. The question is 

 asked as to whether the growth of maize was checked by the diversion of some 

 of the water to the weeds and two reasons are given for believing that while 

 the available water may have been a factor in this respect there must have 

 been some other influence also. Thus the total product was not so great on the 

 weedy plats as on the cultivated plats, and it is entirely probable that 

 although in a dry season all the plats would have had a lower percentage of 

 water the cultivated plats would have produced more maize than the weedy 

 plats produced this year. 



A table is given showing the water-soluble nitrogen in parts per million of 

 dry soil on a cultivated plat and on a millet plat at different dates, and also 

 on a plat to which nitrate of soda was applied. It is pointed out that on July 

 2 the cultivated maize plat contained 96 parts of water-soluble nitrogen per 

 million of dry soil, while the maize and millet plat contained only 10 parts. 

 The maize where millet grew was of a lighter green color and smaller size 

 than where it was grown by itself, and it was reasoned that the addition of 

 nitrate of soda should cause the maize to recover its green color and grow more 

 rapidly than maize and millet not so treated. For this purpose twice the amount 

 of nitrate of soda necessary to supply 86 parts per million of dry soil was 

 applied to 35 hills of a maize plat on July 6, 14, 21, and 27. On July 14 both 

 the maize and millet were much greener than the rest of the plat not so 

 treated, and on July 18 the hills were distinctly larger than the untreated hills 

 of the millet plat and as green as the plants on the cultivated plat. It was 

 found that between July 30 and August 16 the water-soluble nitrogen increased 

 from 160 to 320 parts of NO3. while all the nitrate of soda was applied some time 

 previous to the first date. The application of the nitrate doubled the growth 



