Material. Clover seed, 1 per cent solution of sodium nitrate, 1 per cent solution of muriate of potash, 1 per cent solution of phosphoric acid, and a saturated solution of limewater.

Apparatus. 100-cc. wide-mouthed bottles, Geneva seed-testers. It has long been known that certain chemical fertilizers, as well as certain forms of other chemicals, have some influence on the seed, in the soil solution as well as in an aqueous solution.

1. Count out four lots of one hundred seeds of the clover. Place each lot in a wide-mouthed bottle and cover them respectively with a 1 per cent solution of sodium nitrate, a 1 per cent solution of muriate of potash, and a 1 per cent solution of phosphoric acid, allowing each lot to remain in its respective solution for twenty-four hours. Remove each sample, and germinate in the Geneva seed-tester. Place the fourth batch untreated in the seed-tester to serve as a check. Tabulate and discuss your results in each case. Plot a curve showing the per cent of germination with each of the fertilizers and also when no fertilizer is used. Does it pay to allow a commercial fertilizer to come in direct contact with the seed? Discuss.

2. Mix in equal proportions a saturated solution of limewater with a 1 per cent solution of each of the following: sodium nitrate, muriate of potash, and phosphoric acid. Now with each solution treat such a batch of seeds as in 1, and germinate. Does the addition of the limewater to the seed aid in preventing any detrimental effect of the commercial fertilizers?

Do the fertilizers all act alike on the different seeds? Which fertilizer shows the most injurious effect? Are the seeds hastened or retarded in germinating by the use of fertilizers? Discuss. Tabulate your results, and plot a curve showing what effect the limewater has when added to each of the fertilizers.

The Effect Of Commercial-Fertilizer Solutions. Student's Notes And Report

Number of seeds germinating

100 90 80 70 60 50 40 30 20 10 0

1

2

3

4

5

6

7

8

9

10

Days

Note. Use different-colored inks or different symbols to illustrate each fertilizer.

Record