PREFACE XV 



Sterilizing the soil in greenhouses has come to be a practicable process. The 

 fumigation practices have been steadily perfected. Increased attention is 

 being given to the introduction of beneficial insects of predaceous or parasitic 

 habits. In California, experiments are being made with a parasite of the 

 codlin-moth. San Jose scale continues to spread with virulence along the 

 Atlantic seaboard, but the first fear of this pest is beginning to pass away. In 

 sprays, the lime-and-sulfnr mixture has come into use over a great expanse of 

 the country. It is doubtful, however, whether this material will gain or hold 

 a paramount place. It is relatively expensive, hard on pump and operator, 

 and difficult to make. There is a marked rise of confidence in the ability of 

 man to control pests and diseases. 



A good many special methods and special crops have come to the fore. 

 The growing of plants under shade of cheese-cloth has received much atten- 

 tion. The growing of dwarf apples and other special forms of garden fruits 

 has aroused new interest. The interest in ginseng continues to spread. 

 Grolden-seal and snakeroot have come to rank as commercial plants. The 

 whole subject of specialty -fai'ming seems to be receiving increased attention. 



It is evident that there is a growing taste for ornamental plantings and a 

 rising appreciation of what constitutes intrinsic beauty in plants. This prog- 

 ress is of course most marked in what we formerly considered as the West, — 

 the states of the prairies and the plains. These countries are maturing; the 

 epoch of pioneering has passed; physical wants are being met; the old houses 

 are being replaced: consequently, there is reason and opportunity for giving 

 attention to the environs of the home- seat. Throughout the country I think 

 that I see a distinct tendency to better treatment of the home -grounds, — the 

 gradual giving up of mere "beds" and meaningless scattered plants, and the 

 making of an open-centered lawn with attractive border planting. There is 

 increasing appreciation of our native plants, as distinguished from imported 

 "novelties" and from merely curious and striking horticultural varieties. The 

 interest in native plants is well illustrated iu the great attention that has been 

 given recently to the hawthorns, or members of the genus Cratfegus. These 

 bushes and small trees are peculiarly characteristic of eastern North America. 

 The botanists have always been confused as to the number of species, and the 

 tendency has been to regard them conservatively. Now, however, the freest 

 interpretation of specific lines has come into vogue, as a result of more 

 careful study, and it is considered that we have several hundred species 

 in our flora. The present interest in the genus is bound to call attention 



