43 
“ WITHER-TIP ” OF ORANGE AND LEMON. 
(Phoma omnivor a n. sp.) 
There is a disease of both Orange and Lemon trees, which have 
been sent to me from West Australia and South Australia, as well 
as from different districts of Victoria, and I happen to have it on 
an Orange tree in my own garden. It is called by most growers 
“Die-back,” because the twigs die from the tip downwards, but it 
has nothing to do with the disease known under that name in 
Florida. The term is a very convenient one, so long as no 
definite cause is known, and had the name not been appropriated 
I would probably have used it as fairly descriptive of the present 
disease. However, I have named it “ Wither-tip,” since the leaves 
as well as the shoots often wither and die from the tip downwards. 
This disease, locally called “ Die-back,” is also known in New 
South Wales, and in the Annual Report of the Department of 
Agriculture, Queensland, for 1897-8, just received, it is reported 
on Citrus trees of the Darling Downs, &c. So the disease occurs 
in all the colonies, and may have been in existence for some time 
without being specially recorded. 
Mr. Quinn, of South Australia, in forwarding mo the specimen, 
wrote under date of 2nd September, 1898 :—“I am taking the 
liberty of forwarding in same packet a twig cut from a Lisbon 
Lemon, which my correspondent says is illustrative of the manner 
in which branches here and there upon the trees throughout a 
plantation are dying out.'” He also says Oranges alongside are 
quite healthy. 
Then Mr. Heape, of Dandenong, under date of 8th December, 
1898, wrote :—“Accompanying this you will find a collection of 
Lemon sprigs with ‘Die-back ’ on them. The lot marked A, I 
found upon an Orange tree, and, strange to say, it is the only tree 
out of the thirteen Orange trees w f e have that shows it, and from 
off the only tree that was pruned. Of course it may not bo ‘Die- 
back.’ ” Roth the Orange and Lemon twigs as well as the leaves 
accompanying them were badly affected with the “ Wither-tip ” 
fungus. 
The solitary Orange tree in my garden, aud indeed the only 
Citrus tree there, had shown signs of weakened vitality for the 
last two or three years, principally owing to the drought, and 
this season it became very marked, only a few flowers being 
formed, and the fruit when it reached about the size of a pea 
becoming black or brown. A number of the shoots were dead 
from the tips, principally the lower,' but also the upper, and the 
affected shoots towards their base often sent out water-sprouts. 
It would appear that Lemon trees aro specially subject, but the 
disease is also spreading to Oranges. 
