CULTIVATION OF THE ORANGE TREE IN SPAIN. 563 



gardens, where the trees are very numerous and where the trunks are 

 very close together above all in such spots as the hollows of valleys or 

 humid plains the trees should be thinned out in such a manner that 

 the branches of the trees can not interlace, and that the atmospheric 

 fluids may have free access on all sides. 



Ulcers. When a tree receives a wound penetrating to the ligneous 

 part and leaving the same exposed to the air, atmospherical humidity, 

 and rain-water, it alters the exterior coats of whiteness and promotes 

 the spilling or wasting of a dark liquid of much acridity. This spilling 

 or wasting impedes the formation of small excrescences on the edges of 

 the wound, which are the commencement of its cicatrization, so that in- 

 stead of the wound closing up, it continues opening more, little by 

 little, gradually changing the bark around it and the ligneous part of 

 the tree. Such a wound may cause the death of the tree. This disease 

 is known by the name of " Ulcer " or " Gutter." The ulcers are pro- 

 duced with much greater facility when the wounds present a less 

 united superficies and are more separated from the vertical, as in such 

 cases the rain- water is better retained in them. The most efficacious 

 remedy to be employed in such cases is as follows : Commence by re- 

 moving all the altered part until a perfectly clean wound is presented, 

 which should be left in this state and in contact with the air for one or 

 two days to dry it up, after which it should be completely anointed 

 with ointment. Several ointments have been proposed as effective, 

 viz, first, the " Ointment of San Fiacre," composed of clayey soil, cow 

 dung and goats' hair or wool, and afterwards a grafting mastic, which 

 should be composed of substances not liable either to melt under the 

 influence of the sun, or crack from frost. One of the best compositions 

 is the following: 



Per cent, of weight. 



Resin 28 



Burgundy pitch 28 



Yellow wax _. 1(5 



Tallow 14 



Sifted asbes orocher 14 



100 



This mixture should be applied sufficiently warm as to be in a liquid 

 state, but not so much so as to effect the texture of the trees, applying it 

 with a brush. This ointment should be preferred to those which become 

 defective through heat and are washed off by rains. 



The disease of the orange tree, known by the name of Mai de Goma, 

 is the most to be feared, as it causes such immense losses to cultivators. 

 This disease consists of a gummy oozing, generally occurring either in 

 the spring or in the autumn. It attacks either the trunks of the trees 

 just above the surface of the soil, or else the roots themselves. This 

 disease commences to show itself by some drops of gum appearing on 

 the trunk, which still appears sound, but this spilling continues increas- 

 ing, the bark is perforated, and the flow of gum augments, being fluid, 



