54 ■ l)p:i'aktmental kepokts. 



work on plants under (ilass. 



The increasing" demand for information upon matters pertaining to 

 the cultivation of plants under glass led to the enlargement of the 

 work during the year. This i)articular line of horticulture is increas- 

 ing rai)idly in importance, owing to the fast growth of cities and the 

 demand for the highest products of the gardener's skill. Over 

 §12,000,000 worth of cut flowers are sold annually in the United 

 States, and the value of the plants is nearly as great. Owing to the 

 intensive nature of this work, every detail must 1)e looked after with 

 the greatest care. During the year special efforts have been made 

 in the direction of studying the diseases of carnations, Easter lilies, 

 violets, and other greenhouse crops, and experiments have been carried 

 on with a view of getting information as to the best methods of prevent- 

 ing them and at the same time increasing the value of the products. 

 Prevention of diseases of greenhouse plants must come largely through 

 a knowledge of the best methods of handling the j)lants themselves, 

 so that many lines of work are inv^olved. Watering, feeding, and 

 methods of propagation are all important factors and have received 

 full consideration. A bulletin on a disease affecting carnations, to 

 which the name Stigmonose was given, was issued during the year, 

 and other publications are also in press and will be issued at an early 

 day. With a view of obtaining authentic facts in regard to the 

 development of the industrj? under consideration, the Division col- 

 lected during the year information from all parts of the United 

 States. More than 12,000 circulars were sent out, and the results of 

 this inquiry, together with information obtained from other sources, 

 were published in the Yearbook of the Department under the title 

 "Progress of commercial growing of plants under glass." 



TRU(^K AND GARDEN CROPS. 



Work on truck and garden crops has been confined for the most 

 part to tomatoes, lettuce, cantaloupes, and cabbage. A number of 

 diseases of the crops in question have been studied and experiments 

 inaugurated with a view of finding a means of preventing them. 

 During the past six or eight years tiie tomato crop in Maryland and 

 adjacent States has been seriously injured by blight, which attacks 

 the foliage early in summer and soon kills the plant. This blight 

 is produced by a fungus, which it is believed may be prevented by 

 spraying. In order to test this treatment experiments were inaugu- 

 rated during the year and are still in progress. 



DISEASES OF FOREST TREES. 



The work on the diseases of forest trees outlined in my last report 

 has been continued. This work is being carried on in cooperation 

 with tlie Division of Forestrj^ of the Department and the Shaw School 

 of Botany in St. Louis. The special agent in charge of the investi- 

 gations. Dr. Hermann von Schrenk, is instructor in botau}* in the Shaw 

 School and has excellent facilities for carrving on the work. During 

 the 3'ear he made a trip into the forests of Maine, and through assist- 

 ance furnished by the Division of Forestry good facilities were obtained 

 in the matter of studying a number of the diseases affecting the forest 

 trees of that region. As a result of this work, two bulletins have been 

 prej)ared and are now going through the press. 



