December, 1908.] 



555 



Plant Sanitation. 



latter have been adapted to the some- 

 what different needs of the former. The 

 use of culture media, though not so 

 absolutely necessary for elementary 

 work in pathology as it is in bacterio- 

 logy, is, however, very common, and, 

 doubtless, special media, tor special 

 organisms are more numerous here than 

 in the allied sciences. Since Dr. Burrill, 

 of the University of Illinois, demon- 

 strated in 1879 that in one instance at 

 least, the pear blight, a plant disease 

 might be caused by bacteria, many 

 diseases have been shown to be of similar 

 origin, and here naturally the patho- 

 logist becomes very closely allied with 

 the bacteriologist. 



Of more and more importance to the 

 country is forestry, on which, eventu- 

 ally, large portions of the land must 

 depend for rainfall and for timber. 

 With this is closely allied our science of 

 plant pathology. There are many 

 diseases of trees, which, unless curbed, 

 threaten the growing of forests. One 

 need but to refer to the " punk " disease 

 of the longleaf and of the shortleaf pines 

 and to similar decays of other forest 

 trees to justify this claim. Indeed, this 

 is so important that a forest pathologist 

 has recentlv been appointed by the 

 Government to study these diseases 

 more carefully. It is unnecessary to 

 dwell upon the increasing importance of 

 the science to agriculture, for we have 

 already noted their close relation. 



We have seen that Botany in all its 

 phases is intimately associated with the 

 study of plant diseases, but now we will 

 consider what other sciences have an 

 interest in it. 



We turn naturally to zoology as the 

 science next to botany, and in many 

 ways it may well be so considered. To 

 plant pathology it is related chiefly 

 through the "pathological conditions 

 which arise as a result of the attacks 

 of various worms, insects and even 

 higher animals. In this way, many 

 galls, such as the well-known oak-galls 

 and the nematode root-gall, which 

 inflicts so much damage, originate. The 

 stripping of the leaves from trees, and 

 the ever-present injuries to farm pro- 

 ducts cause conditions for pathological 

 study. Many diseases are transferred 

 from plant to plant by animals of nearly 

 all classes, and the combined efforts of 

 zoologists and of pathologists will be 

 necessary to combat this evil. Dr. 

 Erwin F. Smith enumerates bees, the 

 potatoe beetle, snails and slugs as known 

 transportation agents for various dis- 

 eases. Moreover, we do not yet know 

 how many diseases of animals, both 

 domesticated and wild, may be due 



directly or indirectly to plant diseases. 

 Oases have been reported where serious 

 results have attended the feeding of 

 diseased fodder to live stock ; and flour, 

 made from infested grain, may cause 

 serious results in man. — Science, Vol. 

 XXVII., No. 703, June, 1908. 



BUD ROT IN THE PHILIPPINES. 



The bud rot is at present very pre- 

 valent in Lazaan, Sungi, and Ylaya. 

 It is present, but does less damage, 

 in two other of the upper barrios of 

 Lilio. There are a few scattered cases 

 in Balauacan and Sinipian, barrios of 

 Nagcarlan, and probably in Pagsauitan 

 and elsewhere. Captain Grove has heard 

 that many years ago it practically wiped 

 out the coconut industry of Lucban. 

 And I have been told that it was very 

 destructive about five years ago in 

 Sariaya. 



In the badly infested districts there 

 are patches where almost every tree 

 is smitten, and larger ones where fully 

 half of the trees are dead or dying. 

 Although the disease has been present 

 in Nagcarlan fully ten years, the damage 

 now in evidence has been done, at the 

 outside, within three years. Dead trunks 

 of coconuts do not usually stand for 

 two years, but I am told that trunks 

 of trees killed by bud rot stand for 

 rather more than that period. However, 

 I have not found the naked trunks 

 more numerous than those with some 

 old leaves still at the top ; and the 

 latter can hardly have been attacked 

 as much as one year ago. The im- 

 pression made upon me is that condi- 

 tions favourable to it the disease will 

 kill half of the trees in a single year. 

 Under less favourable conditions it is 

 less violently epidemic ; and it is my 

 present opinion that in most parts of 

 the Philippines it will never prove vio- 

 lently destructive The fact that a given 

 tree escapes one year is no guarantee 

 that it will not be killed the next. 

 Under conditions favourable to the dis- 

 ease it is only a question of time, unless 

 vigorous restrictive measures are carried 

 out, when practically every tree will 

 succumb. The inhabitants of the in- 

 fested district are almost unanimous 

 in stating that a tree which once shows 

 symptoms of bud rob is sure to die. 

 Only two man told me otherwise, and 

 they agreed that recovery was very rare. 

 The climatic condition pdrmittiug the 

 disease to ba exceedingly destructive is 

 a very moist atmosphere. The uppsr 

 b alb of co3onub country about Mount 

 Binajao is ona of the most humid 



