DISEASES OF CITRUS TREES ] 53 



hand pressure on a sponge. The pulp is clear orange-red, 

 sweet, with a pleasant acidity and delicate aroma. 



The mandarins are distinguishable into two classes, 

 (a) the true mandarins having an orange-coloured peel 

 and flesh, and (b) the tangerines in which the flesh and 

 peel are of a deep orange or red colour. These last 

 are not grown in these Islands. 



The mandarin orange is rarely affected by gumming, 

 and as it grows freely from seed, it may be budded on 

 own seedlings, but our gardeners bud it invariably on 

 sour-orange stock, for the reason that this stock is more 

 handy, and also on the supposition that by budding on 

 the sour orange the fruit improves in size and flavour. 

 Bud sports of the mandarin orange are numerous. Thus, 

 we have the large-fruited mandarin often miscalled 

 tangerine, the round mandarin, and the pear-shaped 

 mandarin in which the fruit is markedly elongated 

 towards the stalk-end, but they are never propagated 

 as special forms, the common type being considered 

 more commercial. The jnandarin is a heavy cropper, 

 instances of full-grown trees producing a crop of 250 

 dozen being frequent. The Satsuma Orange is a true 

 mandarin introduced a few years ago, but its colour 

 is a deeper orange than the mandarin. The fruit is 

 seedless, and the tree is entirely thornless. It is best 

 budded on seedlings of the mandarin orange, as it is 

 said not to do well when budded on the bitter orange, 

 but it may be rebudded on plants of the ordinary 

 mandarin. 



DISEASES OF CITRUS TREES. 



Citrus trees are liable to the following non-parasitical 

 diseases. 



i. CHLOROSIS. (M.=marat tr&tfy. Is the disease of 

 non-adaptation or of disagreement of the tree with its 

 environment, and is a disease to which all plants bearing 



