10 A YEAR IN AGRICULTURE 



the houses we live in, the vehicles we ride in, and the art we 

 enjoy, the plant interest is an important factor. Most of 

 the world's great industries are carried on with raw mate- 

 rial derived from plants. The farmer, the gardener, the 

 lumberman, the carpenter, the shipbuilder, the cotton manu- 

 facturer, the sail-maker, and even the miner, all depend upon 

 the products of the plant life that is or was on the earth or 

 in the sea, ; the -air which we breathe is purified partly 

 through the processes by which the green plants live. Human 

 life could ' not- continue long without the aid of substances 

 produced by the life and growth of plants. 



How plants grow. Let us begin at the beginning of a 

 typical plant growth and trace the steps and processes in 

 its development. If we start with the seed of a higher plant 

 for our study, we have not begun at the beginning, for this 

 was made back in the blossom when the seed was forming. 

 The seed of the plant consists of a tiny plant imbedded in 

 a cotyledon, the bulky portion of the seed, resting in its 

 development until favorable surroundings start it again in 

 growth. 



A good seed is, of course, alive and healthy. It is true to 

 the parents which produced it. It is large and plump, show- 

 ing that it has a maximum amount of food supply. In quan- 

 tity it is clean and free from foreign matter. "When this 

 seed is placed in medium temperature, with sufficient moisture 

 and plenty of air, it will begin to grow, to germinate. This 

 favorable surrounding for most seeds is made in the soil of 

 the seed-bed. By germination we mean that the moisture 

 absorbed into the cotyledons begins to dissolve the starchy 



