23 
and acid phosphate were mixed with the soil in such quantities that 
during the period of growth each pot received 4.1 grams of nitrogen, 
3.1 grams of phosphoric acid, and 6.7 grams of potash. The ferti- 
lizer was given in different applications to prevent too great a quan- 
tity of soluble salts being present at one time and also because there 
was probably a certain loss by leaching caused by the heavy showers. 
The plants were grown for a period of 10 months, and during this 
time the check plants made a growth equal or superior to that of 
plants in the field. A record was kept of each plant in regard to the 
appearance of chlorosis. After 10 months’ growth the plants were 
cut and weighed in the green condition. 
The principal purpose of the experiments was qualitative—to 
observe the effect of calcium carbonate in producing a chlorotic 
appearance of the plants, but the comparative weights show in a 
general way the condition of the plants and give an idea of its effect 
on the growth. Accurate quantitative data of small differences in 
growth can not be obtained in pot experiments with pineapples, as 
it is impracticable to grow enough individuals to secure a fair average. 
In experiment I the sandy soil No. 213 was used and the limestone 
No. 216. The five check pots contained no lime; the other lots of 
five pots each contained, respectively, 10, 20, 30, 40, and 50 per cent 
of calcium carbonate. Suckers of Red Spanish pineapples were 
planted. In the next table are given the appearance of the plants at 
four, six, and nine months, and the average green weight. 
The object of the experiment was to see whether the addition of 
calcium carbonate to a good sandy soil would cause it to produce 
chlorotic plants. By consulting the table it will be seen that all the 
check plants made a good growth and remained dark green during 
the 10 months; that all the plants in pots containing carbonate of 
lime showed varying degrees of chlorosis and a great depression in 
growth; that the chlorosis was most intense in the pots containing 
the greatest amount of lime. (PI. IJ, fig. 1.) 

Results of experiment in which calcium carbonate was added to sandy soil. 




Average 
green 
eae, poe. Appearance of plants during growth. woee oe 
s end of 10 
months. 
Grams. 
HOCK ne ocean All plants dark green throughout the experiment.........--.....--.-------- 1, 022 
10 per cent. ---- Color of all 5 plants lighter than check at fourth month; at sixth month 2 596 
plants slightly chlorotic; at ninth month all slightly chlorotic. . 
20 per cent... .-- At fourth month 2 plants slightly chlorotic, others light green; at sixth 584 
month all slightly chlorotic; at ninth month all 5 chlorotic. 
30 per cent. --- - At fourth month all 5 plants light green; at sixth month 4 plants chlorotic; 623 
at ninth month all chlorotic and 3 very strongly. 
40 per cent....- At fourth month 4 plants slightly chlorotic and 1 plant light green; at sixth 549 
month all chlorotic; at ninth month all 5 strongly chlorotic. 
50 per cent... .- At fourth month all slightly chlorotic; at sixth month all chlorotic; at ninth 400 
month all 5 strongly chlorotic. 

[Bull. 11] 
