332 



NEW YORK. 



Prof. C. S. Plumb states, as the result of a research made by him- 

 self during the summer of 1886 at the New York Agricultural 

 Experiment Station, on the growth of maize and its dependence upon 

 climate, the following conclusions : 



(1) That maize makes a positive daily growth upward from the 

 appearance of the plant above ground till the plant has reached its 

 maximum height. 



(2) That the variation in the development of the plant from day 

 to day and week to week is not controlled by meteorological condi- 

 tions, for of two plants that one which is the most backward at the 

 beginning of the season may eventually become the stronger, larger, 

 and more vigorous of the two. 



The measures on which these conclusions are based (see Agr. Sci., 

 Vol. Ill, p. 1) were made day by day upon seven individual plants, 

 and the aA^erages are given in the folio Aving table ; the date of plant- 

 ing was May 21, 1886, and the dates of sprouting extended from May 

 31 for plant No. 1 to June 4 for plant No. 7. 



Date of observation. 



height 



of 7 

 plants. 



Sums for preced- 

 ing 7 days. 



Air 

 temper- 

 atures. 



Soil 

 temper- 

 atures. 



Sunshine 

 dura- 

 tion. 



June 6 



June 13 



June 20 



June 27 



July 4- 



Julyll 



July 18 



July 25 



Total. 



Inches. 

 3 

 8 



14 

 23 

 35 

 41 

 47 



F. 

 452 

 475 

 494 

 466 



Days. 

 28 

 60 

 50 

 46 

 84 

 50 

 53 

 50 



Inches. 

 0.76 

 .0 

 ■0 

 .40 

 .0 

 .71 

 .73 



4,678 



The unsteadiness of the growth is very notable. There was a 

 steady increase up to July 4 and then a drop for fourteen days, but 

 growing more rapidly during the last period. AVhen the greatest 

 growth was made in the eighth or last period, the total air and 

 soil temperatures were less than in the fifth period, when great 

 growth was also made. During this last period of greatest growth 

 the rainfall was large, while during the previous period of great 

 growth the rainfall was zero. Evidently it needs a peculiar combi- 

 nation of rainfall, temperature, and sunshine to bring about the 

 rapid growth. According to Frear, the very rapid growth of plants 

 observed immediately after rainfall is largely due to a simple expan- 

 sion of the cells with water. 



Although a soil gains some nitrogen from the air as brought down 



