HOW SEEDS " COME UP " 73 



in which the greater part of what was once the seed is 

 forced up through the soil, and appears above the surface. 

 If the seeds of such plants are planted deeper than four 

 or five times their thickness, the plantlets will be unable to 

 lift the soil above them, and so can not come up at all. 

 To this class of plants belong, besides the bean and radish, 

 the beet, parsnip, carrot, squash, cucumber, melon, clover, 

 buckwheat, and, in fact, almost all the common farm and 

 garden crops, except plants of the pea family and of the 

 grass family. 



Rule for Depth of Planting. The following rule may 

 be safely followed for the seeds commonly planted on the 

 farm and in the garden: Seeds of plants that come up 

 without thick seed leaves, as Indian corn, wheat, rye, 

 oats, barley, millet and other grasses, peas, lentils,' and 

 vetches, may be safely covered to ten times their thickness. 

 Other seeds should not be covered more than five times 

 their thickness. As a rule, no seeds should be covered 

 deeper than is needful to insure a supply of soil moisture. 

 It is often desirable to sow a crop in the orchard in sum- 

 mer, when the soil is rather dry; for this purpose, it is 

 important to choose one the seed of which may be deeply 

 planted. 



QUESTIONS AND EXERCISES. 



1. Name several plants that, in germinating, carry the 

 seed -leaves above the ground. Name several plants that, 

 in germinating, send up slender stems. 



2. Give the rule for depth of planting for these two types 

 of plants. 



