ORCHAKD MANAGEMENT. 119 



the introduction and growth of the bacterial spores. He 

 says: " Pectose is accompanied in the vegetable tissues in 

 which it is found by a "erment pectose, sometimes soluble 

 and at others insoluble, which possesses the property of 

 transforming pectose and pectin into pectic and metapec- 

 tic acid successively. Pectic fermentation plays an im- 

 portant part in the conversion of ripe fruits into an 

 ever-ripe, half-rotten, or sleepy state. It also assists in 

 the formation of vegetable jellies. In fact the transforma- 

 tion of the natural juices of fruits into jellies is a result of 

 the metamorphosis of pectin contained in these juices into 

 the pectosic and pectic acids. Pectic fermentation is 

 effected at about 95 Fahr." It may be that with further 

 investigation it will be discovered that a ferment precedes 

 the attack of bacteria. If this proves true it would not 

 disturb the fact that blight can be extended by inocula- 

 tion. 



128. Do Cover-crops Dry the Soil? It is urged by those 

 who yet favor continued orchard culture to conserve 

 moisture that cover-crops rob the fruit trees of needed 

 moisture at the time when fruit needs it most for perfect 

 maturation. The first and even second leguminous cover- 

 crop sown in a bearing orchard will result in diminished 

 supply of soil moisture as compared with the plan of con- 

 tinued culture. But this only favors the perfect ripening 

 of relatively young trees. But the turning under of two 

 or three leguminous crops soon gives a supply of humus 

 and nitrogen that so changes the mechanical texture of 

 the soil that it will hold moisture through the season far 

 better than the cultivated ones that each year become more 

 destitute of needed humus and nitrogen. 



129. Protection from Mice and Rabbits. In the United 

 States and Canada field-mice are found in all parts that 

 are liable to girdle the stems of young orchard trees. A 



