428 THE PLITM. 



if the tree is of the slow or slender-growing varieties, it will need no 

 farther pruning than the above-named standard. If it is of the 

 strong, rampant-growing kind, it will require both root-pruning, 

 (i. e., passing round the root of the tree in a circle distant from the 

 body two feet for a tree of ten feet high, and with a long, sharp 

 spade, cut off all the roots); and at the same time shorten back the 

 year's growth one-half. This is best done in August. This mode is 

 especially calculated for the Western prairies and the warm South- 

 ern States. 



Cultivation. Like all other fruit trees, the plum does best when 

 the ground is often dug or hoed around. Many growers are also of 

 impression that frequent stirring the soil prevents attacks of curculio. 

 Trees planted where swine have run among them are generally 

 healthy and fruitful ; but whether it is owing to the stirring of ground 

 by their rooting, or food supplied the plants in their excrements, is 

 yet a question undecided. 



Manures. The plum requires abundant food in the soil, and this 

 is generally best supplied by animal manure ; and where abundant 

 supply of animal manure has been given, salt will be found highly 

 beneficial : the proportion should be controlled somewhat by the 

 quantity of animal matter contained in the soil ; but a dressing of 

 half an inch deep over the whole ground, if applied in the Spring, 

 may be regarded as a medium. The benefit to the tree of this 

 application will be in its tendency to an equable state of moisture in the 

 soil. Ashes, in soils devoid of lime and the phosphates, will be 

 found beneficial : two bushels to a tree twelve feet high, and in bear- 

 ing state, will be a guide ; larger trees requiring more, and smaller 

 ones less. Brewer's grains are also valuable as a manure, when 

 they can be obtained at prices corresponding with the value of ani- 

 mal manures. 



Diseases. The Black Warts, Knots, or Black Gum, is a disease 

 affecting many plum trees at the North. In the Southern States it 

 is not yet much known. Its cause is variously attributed by some 

 to insects (membracis bubalis), (see Harris's Treatise on Insects); 

 by some to inherent cause from its parent; by some to temperature 

 and atmospheric change on the health and vigor of the tree ; and by 

 others to a diseased state of sap. After noting that it first appears 

 in a neighborhood on trees grown from suckers, or propagated on 

 suckers or unhealthy stocks, we are inclined to a support of the last- 

 named cause. Trees in a judicious, rather high state of cultivation, 

 and grown or worked on good, healthy seedlings, are rarely subject 

 to it. And a tree diseased by inoculation may be recovered by 

 appliance of abundant food at the roots, cutting away the apparent 



