116 
RELATION OF WATER TO CROPS. 
KE. Wollny has studied the relation of the irrigation and rainfall to 
the development and productive power of plants in cultivated fields, 
and the following summary is essentially as given by him in Volume 
X of his Forschungen for 1888, page 153. 
An early investigation of this subject was made by Tlionkoff, who 
filled five large tubs with soil and sowed buckwheat in each on the 
15th of May; each tub was then watered regularly with a definite 
quantity of water, the total quantity used being given in the second 
column of the table following. The relative quantities of buckwheat 
harvested at the end of the season are given in the third column and 
the straw is given in the fourth column. The weight of the buck- 
wheat originally sown in each tub was the same, viz, 0.154 gram. 
Weight of green har- |Weight of dry| Ratio 
vest. harvest. pene of 
Total Pi | ber SAT 
TENG water |of ker- AyaGl 
1 Sis tbea tol gam | nate terest Delonas 
plied. | Grain.) Straw. total, | Grain. Straw.) har- Pattie 
yeaa | |vested.| ocd 
Liters. \Grams.|Grams.| Gra ms. Grams. 
Pin) 22 25.008)) 1.8941" 26/1041" 27,90']). 1 68h| Barbet) cr ae 4s 
Pa eae Sets eb yen | 12.50 6.15 | 58.85 | 65.00 5.47 8.47 283 100 
Pe te oe eer eel ae phe) 1.95 | 23.03 | 24.98 1.73 4.55 93 46 
bE SA 2 ere 3.12 .58 | 9.42] 10.00 .52 1.41 | 37 14 
Breese el ss 1.56 10 | 2:20) 0h 2530))25 1200 580: })t 4, Sap 3 
These figures show plainly that the plants in tub No. 2 were most 
favorably situated. Probably No. 1 had too much water and Nos. 3, 
4, and 5 too little. 
Haberlandt, in 1866, experimented on the quantity of water needed 
in the growth of plants in three plats of 14.41 square meters each; 
of these No. 1 received no artificial watering; No. 2 was watered once 
a week, except in great droughts twice a week; No. 3 received a 
double quantity once a week. These quantities corresponded to a 
rainfall of 6.46 millimeters for No. 2 and 13.92 millimeters for No. 3. 
The total quantities for the season were 96.96 and 193.92 millimeters. 
The natural rainfall was as follows: 
Month, 1886. Beiny Rainfall. 
nim, 
Maren. 5.2135 7c: pe ek. eb ee i oa Ae Se eee nee ee eee 17 40.98 
INS apETTY [9 Ae NO ll ke eB ff Peak SS? SURE ES ee TESTI ee 15 | 35. 38 
Ma yiee 2 sco cts cote oe ee ag ee ee eee ul | 52.20 
UNC ere, SET. I ee ee ee oe 2 Re ei ee ee 13 46. 03 
JU yt p2csc bo ct cc Set ot sched ee ee ee es SY 17 | 34. 40 
POCA scott a ORS mee ea 73) 208.99 
