THE BUD-ROT OF PALMS IN INDIA. 233 



of high humidity or during heavy dews spores would develope in 

 this situation, freely exposed to the wind. A second condition in 

 which there may be air-borne infection occurs when the tube of 

 leaf-sheaths begins to disintegrate as an effect of the disease. In 

 old cases the outer leaf -sheaths wither and fall away and eventually 

 nothing is left but a bare pole. In these old withered sheaths no 

 spores capable of germination have been found, but it is quite pos- 

 sible that they occur, and if this is so, they would be a means of dis- 

 semination. A third condition is the result of the stripping of the 

 outer leaves for thatching and still more in some localities for fibre. 

 In the operation the old leaf bases are torn away, and it is not un- 

 common to see leaf -sheaths that are still almost white from their 

 internal position, exposed. In infected trees this must offer consid- 

 erable opportunities for aerial dissemination of the spores. It is 

 doubtful how far the above conditions are sufficiently frequent to 

 account for the intensity of the epidemic. It appears that if this 

 were a common method of spread, the area affected would by now 

 be far greater than it is. Air-borne infection is always rapid and 

 instead of the disease being confined to one small district, it would 

 be found throughout the country. However, it is quite possible 

 that the conditions mentioned above are sufficient to permit of a 

 limited aerial dissemination while not enough to cause rapid 

 extension of the infected area. 



Dissemination of disease by human agency is particularly like- 

 ly where, as in bud-rot, the diseased parts of the plant are habitually 

 handled by persons who afterwards come into contact with suscep- 

 tible portions of healthy trees. As already mentioned, each vil- 

 lage uses the produce in leaves of a large number of palmyras for 

 thatching. In addition a large number of trees are tapped for toddy 

 and jaggery. Over 400,000 palms are tapped for jaggery in the 

 Godavari District (mostly in the upland Taluks) according to the 

 Imperial Gazetteer. For both these purposes the bulk of the palms 

 in the district are climbed at intervals. It is the practice of the 

 climbers to strip off the outer sheaths, both because they impede 

 their operations and because they serve for fuel. Hence the inner 



