48 DEPARTMENTAL REPORTS. 



Black rot of grapes. — In North Carolina and to some extent in adja- 

 cent States black rot destroyed the entire crop of Niagara grapes this 

 season and but a very small percentage of the entire crop of grapes 

 matured. A preliminary trip through this region resulted inopeuing 

 up the question of the efficiency of Bordeaux mixture and the ordi- 

 nary spraying apparatus in preventing this disease in the South. The 

 coming season a thorough study will be made of the subject to deter- 

 mine why growers in the South fail to control this disease with the 

 treatment which is successful in other parts of the country. Plans 

 have been made for carrying on the work at Southern Pines or Tryon, 

 N. C, or perhaps at both places. 



Little peach. — Investigations have been continued on this very 

 obscure disease, and have served to strengthen the evidence of the 

 work last season that the trouble is caused by a minute fungous para- 

 site of the roots. The fungus was found in much larger quantities 

 than ever before, it having increased alarmingly in certain affected 

 localities, and it was also found in fruit for the first time. It does 

 not seem to spread very much to new regions, however. In quite a 

 number of cases orchards affected last year have been totally 

 destroyed the present season. Two methods of dealing with the dis- 

 ease are at least promising — (1) eradication and (2) the securing of 

 resistant stocks. Where growers are on the alert for the disease and 

 promptly pull out and destroy the very first suspected cases their 

 orchards have, almost without exception, remained intact, but where 

 they wait for the trees to ripen fruit and hesitate about prompt 

 removal the disease spreads so rapidly that in three to five years 

 the orchard is practically beyond recovery. As regards resistant 

 stocks, there is but little evidence on this point from our field work, 

 and our conclusion is based entirely on general i^rinciples that hold 

 true in the behavior of similar diseases. Although prompt removal 

 indisputably holds the disease in check, we are not satisfied with such 

 a radical line of treatment, and hope bj'^ persistent investigation of 

 the life history of the parasite and experiments with resistant stocks 

 to work out some method by which all trees may be saved. An experi- 

 ment to test the effectiveness of fertilizers and fungicides when applied 

 to soil around the trees will also be made the coming season. Suffi- 

 cient data on the little peach has been collected to justify the publi- 

 cation of a report at the conclusion of this season's work. While 

 investigating the little peach a number of interesting facts about other 

 peach diseases were gathered and the data will be published during 

 the current year. 



Pear blight. — Pear blight has broken out with renewed severity in 

 Texas, and has been extremely destructive to the Bartlett pears grow- 

 ing on the Pacific coast. (See " Work on the Pacific coast.") A visit 

 to Texas in October is planned to test our method of eradicating the 

 disease by cutting out the hold-over blight. The experiment will be 

 continued during next spring. 



ROOT ROT OF FRUIT AND OTHER TREES. 



The special agent in charge of tlie Mississippi Valley laboratory has 

 made very satisfactory progress in the study of the root rot of fruit and 

 other trees, a disease which causes immense losses in all the great fruit- 

 growing regions. Tlie parasite which causes it has been found and 

 its life history has been partially worked out. Extensive experiments 



