STOCKS FOR CITRUS TREES. 201 



of stock now used for citrus trees in America. For this 

 reason and because of the great foraging power of its 

 roots, it is an excellent stock for use on high, dry soils 

 or on those containing a small amount of plant food, or 

 on soils where the plant food is not readily obtained be- 

 cause of some undesirable soil condition. For planting 

 on low ground, sour orange stock is preferable, and on 

 this class of soils rough lemon should never be used for the 

 kumquat. Attention is called to this point in Bulletin 65 

 of the Florida Exp. Station in the following words : 



"A number of kumquats on rough lemon stock planted 

 on rather moist ground have come under personal obser- 

 vation in which it was found that there was a more or 

 less copious flow of gum from the region just above the 

 union of the stock and cion. In all cases where this oc- 

 curred it appeared that the cion was the only part affected. 

 The trees were in an unhealthy condition. The diseased 

 condition, if we may so designate it, did not appear to be 

 mal-di-goma, though in some respects it resembled it. 

 The trouble may have been due to the fact that the great 

 foraging power of the roots enabled them to collect, in 

 certain soils, more food than the less rapidly growing 

 top could readily assimilate." 



"On the other hand, on soils containing less moisture 

 and presumably less fertility, a number of trees budded 

 upon rough lemon roots have been examined which were 

 vigorous and perfectly healthy. If one desires to use 

 the rough lemon stock for the kumquat on some soils 

 the best plan would be to adopt the method used quite 

 extensively by C. W. Butler, St. Petersburg, Fla. His 

 practice is to insert kumquat buds in sprouts from rough 

 lemon roots which already support and feed a sweet or 

 mandarin orange top. A perfectly healthy union is se- 



