THE MONTHLY BULLETIN. 7 



new growths are a very good type of fruiting wood. If the tree is 

 pruned vigorously enough to get new wood twelve or eighteen inches 

 long, this may be shortened-in as a means of thinning the fruit. Nearly 

 every cluster of buds will have one branch-bud which may be depended 

 upon to continue the growth of the twig. 



One should study the variety of plum he is growing, and prune to 

 get these desirable types of fruiting-wood. If the tree bears heavily 

 and requires much thinning, or if it bears fruit throughout the head 

 one year, and only in the top the next, the pruning has not been severe 

 enough. Head the tree in from the top each year, for little is gained 

 by growing a tall tree. 



It is to be hoped that we have gained something by a discussion of 

 this phase of pruning. If I have not made myself entirely clear, maybe 

 you have the most important points. The time has not Ijeen wasted if 

 we only see the importance of being better observers. We must know 

 our plants if we are to care for them well. 



SOME EXPERIMENTS IN TREATING CITRUS TREES FOR 

 GUMMOSIS AND HEART-ROT. 



By J. A. Prizer.* Chula Vista. California. 

 THE BROWN ROT GUM DISEASE OF THE LEMON. 



Probably no disease that has ever affected the orange or lemon has 

 called forth so many theories as to its cause, or has been productive 

 of such a variety of treatments as has the common gum disease of the 

 lemon. Some few workers from time to time maintained that it was 

 infectious, while others of equally good authority asserted that it was 

 purely of a physiological nature, brought on by any one of a multitude 

 of possible causes. A stake in the roots, crossed roots, improper irri- 

 gation, hardpan, plowsole and a dozen other things were assigned as 

 the cause ; and as the rancher determined the cause in his particular 

 case he removed the stake, crossed root, etc., and in addition the trunk 

 of the gummed tree was slit and painted with neatsfoot oil, carbolic 

 acid or some other material to soften the bark. New growth was fre- 

 quently stimulated by the application of lime, gypsum or some other 

 fertilizing material. It was thus a case of attributing the cause of the 

 disease to some unusual circumstance, and evolving some theoretical 

 cure for the trouble. 



Three years ago we began a systematic trial of all the then known 

 treatments, in order to determine for ourselves which would be most 

 effective in this locality, under our local conditions of soil and climate. 

 The one which proved most satisfactory was the simple slitting of the 

 bark. But in this case the treatment was a success only on very slightly 

 gummed trees. Under no other conditions did any of the treatments 

 prove dependable and trees on which the bark was killed half way 

 around proved to be hopeless and beyond any treatment then known 

 to us. 



*This article Is taken from a report by Mr. J. A. Prizer to Horticailtural Superin- 

 tendent L. B. Barnes of the San Diego Land Corporation and will be appreciated 

 by our readers. — Editor. 



