October, 1910.] 



Every garden in the whole district 

 should be pruned. Success in extermin- 

 ating the blight depends on whole- 

 hearted co-operation. 



If blister-blight should appear in 

 March, pick off blistered leaves at once 

 and spray the surrounding bushes. This 

 may be done till the early rains come. 



In seed beds, new extension and heavy 



Eruning, where the damage from blister- 

 light is considerable, be prepared to 

 expend money on repeated applications 

 of blight-remedies because the benefit in 

 each case would more than pay for the 

 cost of treatment. • 



POTATO WART AND WHITE 

 PINE BLISTER RUST. 



(From Science, Vol. XXXI., No. 801, 

 May 6, 1910.) 



The American Phytopathological So- 

 ciety has passed resolutions as follows :— 



Resolved, That the American Phyto- 

 pathological Society views with alarm 

 the recent introduction into America 

 of two dangerous European plant 

 diseases : the potato wart, caused by 

 Chrysophlyotis endobiotica, Schilb., and 

 the blister rust of white pine, caused by 

 Feridermium stroli, Klebahn. The for- 

 mer has been discovered in Newfound- 

 land. The lattei has been widely dis- 

 tributed in nine of the United States 

 and in the Province of Ontario, but is 

 now believed to have been eradicated. 



Resolved, That the Society deplores 

 the fact that in the absence of a national 

 regulation either in the United States 

 or Canada both Governments are power- 

 less to prevent the continued introduc- 

 tion of these and other dangerous 

 diseases, or their transference from one 

 country to the other. 



Resolved, That on account of the enor- 

 mous financial interests involved in 

 potato culture and in white pine reforest- 

 ation, this society regards the situation 

 as very alarming, and one which 

 warrants radical and immediate action. 

 Even if these diseases do no more harm 

 in America than they have in Europe, 

 the situation is serious ; but every law 

 of biology and all experiences with plant 

 diseases and pests indicate that, in a 

 new climate, with new varietal and 

 specific hosts and with an entire con- 

 tinent in which to spread, both disease? 

 will reach a degree of virulence unknown 

 in Euiope, 



Therefore, Resolved, That this society 

 pledges its support to all legislation in 

 both the United States and Canada 

 looking toward the inspection, quaran- 



7 Plant Sanitatyyri' 



tine, or prohibition from entry, as may 

 be necessary, of all plant material liable 

 to introduce these or other dangerous 

 diseases or pests. 



CACAO CANKER. 



(Prom the Agricultural News, Vol. IX., 

 No. 214, July, 1910.) 

 The canker disease of cacao has long 

 beeu known from all parts of the tro- 

 pical world where this plant is culti- 

 vated, and many different investigators 

 have attempted to determine its cause, 

 and to suggest remedial and suggestive 

 measures for combating it. While suc- 

 cessful to a considerable extent in regard 

 to methods of treatment, none of the 

 earlier investigators can be said to have 

 definitely determined the fungus to 

 which the disease is primarily due. At 

 first sight, it may appear that this last is 

 a point ot' interest only to the mycol- 

 ogist, and not of any importance to the 

 practical man. Actually this is very 

 far from being the case as, it is hoped, 

 will be clearly indicated in the sequel. 

 Apart from other considerations, the 

 definite determination of the fungus to 

 which any given disease is due is of 



Eractical importance because, until this 

 as been done, the biology or life- 

 history, of that fungus cannot be 

 worked out, and without a thorough 

 knowledge of its different forms, its 

 general habits, and its method of attack 

 the best remedial and preventive mea- 

 sures cannot be determined. Such a 

 knowledge of the parasite is also of 

 importance, as it shows at once whether 

 the fungus is one not known to occur on 

 any otner plants common to the locality, 

 or even on other parts of the same host 

 plant, or whether it is identical with 

 some species already well known. 



Until very recently, canker of cacao 

 has been attributed to various species of 

 Nectria, or closely allied genera, the 

 actual species varying somewhat with 

 the part of the world from which the 

 disease was reported. Recently, how- 

 ever, considerable doubt has been 

 thrown on these conclusions by two or 

 three investigators. Mrs. Van Hall, in 

 Surinam, has isolated a fungus from 

 cankered areas on cacao, to which she 

 gave the name Spicaria colorans. (Agri- 

 cultural News, Vol. IX, p. 46). This 

 fungus differed from the species of 

 Nectria usually found associated with it, 

 in that it only produced two conidial 

 forms of spores, and never gave rise to 

 any perithecial stage. As a result of a 

 critical examination of the literature of 

 the subject, Mrs. Van Hall comes to the 



