306 STATE HORTICULTURAL SOCIETY. 



FACTS ESTABLISHED. 



( 1 ) The disease is contagious. It seems to me that experiments 

 1, 2 and 5 settle this point beyond dispute. 



(2) It may be conveyed by seemingly healthy buds when these 

 are taken from diseased trees. This is proved by experiments 2 and 5. 



( 3) Only a very small amount of infective material is necessary, 

 provided it be in the forms of living cells, which can be induced to 

 unite with the actively growing tissues of the tree. 



{ 4) The disease has a longer period of incubation than we have 

 been accustomed to suppose. 



( 5 ) The death of the entire tree occurs, ordinarily, only after a 

 very considerable period, i. e., several years. 



HYPOTHESES RENDERED PROBABLE. 



( 1 ) The whole tree is affected when symptoms appear in any part 

 of it. 



{ 2 ) In some cases, perhaps many, the period of incubation — i. e., 

 the time between the insertion of a diseased bud and the appearance 

 of the disease — is longer than any yet clearly established. 



(3) The disease is also communicated to budded trees in some 

 other way than by bud inoculation. This is probable in case of many 

 young trees, and is almost certain in case of old trees. 



(4) The trees are not infected through the blossoms. This is 

 inferred from the result of the excisions, and from the tact that, in 

 some cases, the disease appears to develop between fall and spring, 

 and to stimulate the blossoms themselves to an unnaturally early 

 development. 



(5) Since diseased trees have been shown to be very full of 



infectious matter, it must be that, for unknown reasons, much of this 



fails to find an immediate entrance into healthy trees. Otherwise, the 



peach would soon disappear entirely. 



Erwin F. Smith. 



PART II— PEACH EOSETTE. 



The second part of this report will be devoted to a peculiar disease 

 prevalent in Georgia, and first referred to as probably a southern vari- 

 ety of peach yellows,* but since described under the name of the Peach 

 Rosette.t 



•Peach yeUow: A Preliminary report. U. S. Dep. Ag., 1SS8. 

 fXhe Journal of Mycology, Vol. 6, No. IV. » 



