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LICHEN. 
_, rhe trunks and branches of neglected trees are sometimes covered 
with a strong growth of lichen (chiefly Ramalina fastigiata, &c.), 
which is most troublesome when the trees are growing in a hard or 
unbroken subsoil. 
When this is the case every effort should be made to improve the 
quality of the soil, and to facilitate vigorous growth. The bark 
should be scraped and the lichen removed. Amongst other evil 
effects, epiphytic growths on the bark afford shelter to noxious insects. 
SNAIL (Helix aspersa.) 
This introduced mollusc is a dangerous enemy to all kinds of 
citraceous plants, and is frequently found infesting the trees in large 
numbers. During the winter season snails collect in large masses in 
the forks of branches, &c.; sometimes as many as from thirty to fifty 
may be found together. The eggs are laid in masses from fifty to 
eighty on or immediately beneath the surface of the soil, or under 
bark or wood lying on the grouud. 
Snails feed on the epidermis of the young branches and leaves, 
causing the growth to be checked; they are especially fond of the 
young fruit, and reduce its value for market by disfiguring it to a 
great extent. The eggs and shells may be easily collected by hand, 
and will form a welcome addition to the food-supply of poultry, &c. 
Citraceous trees, especially the small-leaved oranges, if neglected, 
are liable to decay of the branches, sometimes to a considerable 
extent: the leaves fall, the branch turns brown and decays. This is 
sometimes considered a special form of disease, and termed “ die-back.’’ 
It is, however, simply caused by neglect of pruning, especially when 
the trees are planted too close together; it is rarely seen in trees 
which receive proper attention. - 
The minute mite which causes the disease known as “ orange- 
rust ” has not been observed in the colony, so far as I am aware. 
ON THE BEST STOCKS FOR ORANGES, LEMONS, ETC. 
Orange-growers in New Zealand are not generally alive to the 
importance of selecting suitable stocks, and of planting only budded 
or grafted trees. In many cases stocks are completely discarded, the 
plants being either raised from seed or propagated by layers. When 
a stock is called into requisition, the lemon is usually selected on 
account of its rapid growth and early fruiting. It is, however, the 
least durable of all, on account of its liability to foot-rot and other 
diseases ; so that it is no matter for surprise to find its general adoption 
is everywhere leading to considerable loss and disappointment. 
It is not unfrequently asserted that the climate of Auckland is 
unsuitable for the production of oranges of good quality. I am con- 
vinced that this statement derives its chief support from the inferior 
quality of most of the fruit produced by trees raised from seed. It 
c 
