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the reddish-brown, resin-like exudation, which is so charac- 

 teristic of the disease. These eruptions are very numerous, 

 and in badly affected trees many limbs, from an inch in 

 diameter down to the smallest, become thickly studded with 

 them. This character almost invariably accompanies the 

 disease and is present at all seasons of the year, so that it may 

 probably be regarded as the principal symptom. Trees may 

 be slightly affected, however, and not shew this sympton. 



4. In diseased trees rapidly grown young shoots often droop 

 in a characteristic manner. After starting to push, the twigs 

 gradually bend downwards and the ends turn up a little, 

 giving the twigs a slightly S shaped curved. This, however, is 

 not always a symptom of die-back, being occasionally seen in 

 perfectly healthy trees. 



5. Young twigs frequently develop an abnormal number of 

 buds in the axils of the leaves, where, under normal conditions, 

 only one or two are formed. This over production of buds is 

 often followed by a gummy exudation at these points. Several 

 of these buds from one node may develop into branches, which 

 in connection with the short inter-nodes, frequently give the 

 new growth a somewhat fascicled appearance. This causes a 

 dense foliage and after the new growth which produces this 

 fascicled appearance has died back, the tree takes on a very 

 regular appearance, as if it were clipped. This is very charac- 

 teristic of cases in the middle stage of the disease. In a latter 

 stage large limbs die-back, leaving around the trunk a dense 

 growth of small water sprouts with large leaves. These shoots 

 in turn become stained with the characteristic reddish brown 

 exudations and eruptions and finally die back. In this stage 

 of the disease, which is one of the last, the tree presents a very 

 ragged appearance, many of the large limbs being dead. 



6. The leaves on trees affected with die-back are rather larger 

 and generally longer and more pointed than those on healthy 

 trees. This symptom, however, is not very noticeable. 



7. The foliage of diseased trees is always a very dark green ; 

 indeed this colour, so much desired by some growers, indicates 

 that the grove is on the verge of shewing the disease. 



8. Frenching or spotting of the leaves with white and green 

 frequently occurs in the more advanced stages of the trouble, 

 but can hardly be considered a symptom. 



9. Slightly swollen, stained spots often occur on leaves of 

 trees in a medium stage of the disease. Any slight mechanical 

 injury or injury due to the attacks of the six-spotted mite (red 

 spider) which works in definite spots, is liable to be followed 

 by a swelling of the leaves at the points injured, accompanied 



