470 CITRUS FRUITS AND THEIR CULTURE. 



Treatment. This consists in removing, as far as pos- 

 sible, the detrimental conditions to which reference has 

 just been made and particular attention should be paid 

 to everything conducive to the health of the grove. 



Carefully remove the earth from about the tree, 

 avoiding injury to the healthy roots. With a sharp, 

 strong knife, cut out all the diseased tissue down to the 

 healthy wood. Burn the material removed. With a brush 

 paint the freshly cut wood with solution No. (3), (4), or 

 (5), or sprinkle solutions Nos. (4) or (5) over the cut 

 surfaces and the adjoining soil. 



Leave the earth removed until such time as the tree 

 has recovered, and then it would be better to fill in with 

 fresh, porous earth. In closely planted groves remove a 

 sufficient number of trees to let the light reach the 

 ground. These can be set out in another plot of ground. 

 Disinfect cultivators, plows and harrows with carbolic 

 acid 'after using them in diseased groves, and before use 

 among healthy trees. As a preventive measure, use re- 

 sistant stocks, as already indicated, and where trees 

 have died out, re-set with others budded on sour orange, 

 rough lemon or pomelo, as the soil conditions render 

 necessary. 



Frequently trees may be made to serve some years 

 of usefulness by planting a number of small resistant 

 stocks around the affected tree and inarching them above 

 the injured parts. 



Scab, Lemon Scab, Sour Orange Seal). This citrus 

 disease attacks the sour orange, bitter-sweet, lemon, Sat- 

 suma, Rangpur lime, and it has been found slightly af- 

 fecting the King mandarin, the pomelo and kumquat. 

 In some districts it has become a serious inconvenience 

 in the production of smooth, marketable lemons, but for- 



