MAN'S SYNTHETIC FUTURE — ADAMS 227 



Not too remote from these experiments is that of spraying the blos- 

 soms of tomato plants with 2,4-D, a chemical commonly used for 

 killing broad-leaved plants. This not only causes many more of the 

 earlier blooms to mature into fruit, but the tomatoes formed are seed- 

 less. With this start, let us look forward to seedless raspberries, 

 blackberries, cranberries, and perhaps many other kinds of fruits, 

 such as watermelons, pears, and apples. 



One of the banes of the farmer or the florist is the insect pests 

 that either destroy or greatly reduce his crops. The varieties of 

 insects and mites are many, and consequently different kinds of 

 chemicals have been sought to eliminate them. DDT is effective 

 in the killing of flies, mosquitoes, and many insects that attack 

 plants, but it is not universally good. Several other insecticides 

 are available, each with its special properties for use on a certain 

 type of insect. Periodic spraying of crops, however, is not only ex- 

 pensive but inefficient, since it is impossible to reach all parts of 

 the plant. The chemist must search for a more ideal insecticide. 

 The ultimate will be a chemical, repellent to all insects and mites 

 and innocuous to plants and to higher animals, a substance which 

 when sprayed on the leaves will be absorbed and completely trans- 

 located by means of the plant juices. Why not seek also a com- 

 bination of minerals and fertilizer required as plant food that 

 can be absorbed through the leaves rather than to follow the tra- 

 ditional custom of fertilizing the soil with chemicals, a large pro- 

 portion of which is washed away by the rain before plant absorp- 

 tion has occurred? 



The farmer also requires chemicals to control weeds and to simplify 

 his cultivation problems. Rapid advances have been made in this 

 area, and many chemicals are known that are toxic to certain kinds of 

 vegetation. Chemicals will sometime be available to sterilize the 

 soil completely toward grasses and weeds but not toward the desired 

 crop. Because of the similarity of many plants to each other, it may 

 be necessary to provide a series of chemicals, each of which will ef- 

 fectively kill just one kind of several closely related plants. The lay- 

 man will welcome the day when he can effectively kill the crabgrass 

 in his bluegrass lawn. 



Far more important information will eventually result from the 

 study of plants. Each plant, with the aid of the sun's energy, con- 

 verts carbon dioxide and water in presence of mineral salts into a 

 wide variety of chemicals, such as starch, cellulose, protein, vegetable 

 oils, chlorophyll, and many other complex organic molecules in smaller 

 amounts. These reactions take place at ordinary temperatures under 

 very mild conditions, commonly known as "biological conditions." 

 .In comparison, the chemist is a clumsy operator. He requires massive 



