Feb. 1, 1899.] THE TROPICAL 
AGRICULTURIST. 
527 
San Jose Scaxe iND Brown Scale, 
The San Joae scale, which is still playing havoc 
with the orcharda in Maryland and some other 
eastern States, has long ceased to bo a serious pest 
in California. San Jose is about fifty miles from 
San Francisco, and the place should not have given 
its name to this deadly scale. The aoiile was in- 
nocently introduced into that district from Chili by 
the late Mr. Lick, the great benefactor, whose as- 
tronomical observatory, vfith its immense telescope, 
crowns Mount Hamilton, over-looking the orchard 
district of San Jose. This pest is the true 
pernicious scale, Aspidiotus perniciosus. It preys 
upon all deciduous fruits, except the apricot and a 
certain black cherry, and at one time did immense 
damage in the orchards of California. The effectual 
treatment in this case also was the cultivation of 
the scale's natural enemies. It was cleared out of 
the State as a serious pest by one internal parasite, 
Aphaleinus fuscipennes, and two beetles — the twice 
Btabbed ladybird (Chilicorous bivulnarus) and the 
Australian brown necked ladybird (Rhizobius Too- 
woombae). Nov7 it is found only as a rare insect 
on isolated trees in towns where the scale is able 
to thrive because its enemiea fiy off and have no 
neighbouring trees to light on. The brown scale 
of the orange Lecanium hesperidam, is quite as de- 
structive as the more notorious scerya. Some thirty 
years ago the orange groves of Southern California 
were seriously attacked, and large numbers of 
them were killed, notwithstanding the most vigorous 
efforts of the growers. The disease, however, at 
length died out, having apparently "cursed itself." 
This was before the days of the new sectional 
survey system, but it has since been discovered that 
tho cure was the work of two internal parasites, 
viz , Bucyrtus flabis and Cocoephagus lecani. The 
brown scale has given no trouble for many years. 
Tho yellow scale of Japan, Aspidiotus citrimus, 
gives little trouble, being kept in check by an 
internal parasite, Aspidiotophagus citrimus, and 
sanguine hopes are entertained of findidg eSective 
insect remedies for other peats. 
The Li.mitations of the Systej;, 
The remaining scale which gives trouble, and for 
which no effective natural remedy has been found, 
is the " red scale," Aspidiotus aurantii. Until the 
natural enemy of this scale is found, spraying and 
fumigating will have to be contiuueJ. For the 
various pests of deciduous trees also, spraying and 
fumigation have still to be carried on. Reports, 
however, have just been received from the Los 
Angeles district of another striking instance of the 
success of natural remedies. The ornamental trees 
of the city and surroundings got so bad with scale 
diseases that their removal was seriously contem- 
plated. The beetles got to work, however, with 
such good purpose that now it is believed the trees 
■will soon be clean. It may be asked why this system 
is not so successful in the other States of America. 
The answer is a simple one. It is a matter of 
climate. The beetles are more highly organised forma 
than the scales, and cannot stand the severe winters 
so well. This was foreseen by the Californian dis- 
coverers, and still Eastern people are surprised 
when they make the discovery for themselves. 
There are so many climates in Californian that 
difficulties have been found in getting the scheme 
to work in some districts. Perseverance, however, 
is securing success in unexpected quarters, aid 
means may yet bo found of making the Californian 
scheme of treatment available in regions possessing 
frozen winters. Fortunately there is no climatic bar 
to the the application of the system in Australia. 
Without assistance it kopt tho Parramatta orange- 
trees clean for more than 100 years. It probably 
eaves the Australian continent from bsing devoured 
by locusts, and vigorous research should be con- 
tinually carried on with the view of applying it to 
all descriptions of insect pests, — Mb. 1, "K. Dow, 
iu the Melbourne Leader, 
THE PKINCIPLES AND PKACTICE OF 
PRUNING. 
(Concluded from i^rjc 455.) 
As regards the detailed pruning of a tree, this 
must be taken in hand at two periods of the year, 
viz., in the winter and the summer. In the former 
season the most important part of the operation must 
be performed, viz., that dealing with the older wood 
with the training of the parts of the tree, and the 
more careful and accurate preparation for fruit-for- 
mation ; for more can naturally be done during the 
dormant condition of the tree, when the sap is at 
rest, than during the summer, when life is active. 
In the summer it is more a question of general thin- 
iiing-out, or suppression of the redundant green twigs, 
which have sprung up everywhere on the tree, as a 
result of the rigorous summer activity of the latter 
which, throwing cff the restraint of cultivation, tends 
to revert to its original ancestral condition. 
The following observations are concerned only 
with general principles, and will not usually, there- 
fore, distinguish between winter and summer-pru- 
ning, the main features of each of which have res- 
lisctively been stated above. 
There are various of the more detailed processes 
in pruning which require really more knowledge, care 
and tact than the untrained practitioner would at 
first imagine. For instance, in pruning-back a main 
lateral branch, this should always be effected close 
above a lower eye or bud, for the outgrowth from 
the latter, which is to form the continuation of tho 
branch, will not tend so much to spoil the general 
curvature of the branch as would an outgrowth from 
an upper eye, for the cut surface immediately above 
its origin would be more quickly covered, owing to 
the fact that the tissues increase in thickness more 
rapidly on the upper than on the lower surface of 
a shoot, and thus the even continuity of the new 
out-growth with the branch would bo the sooner 
established. Moreover, the reason why it is always, 
in the case, at least, of these main " branches ad- 
visable to prune to an eye, lies in the fact 'that 
if a dead stump of wood be left beyond an eye, the 
outgrowth from the latter will not only be consider- 
ably diverted from its right direction of growth as 
an even continuation of the mother-branch, but as 
a result of this, will not draw the sap in such full 
an sufficient quantity to the fruit developing all 
along the whole branch. For it is obvious that 
along a straight or evenly-curved branch the sap will 
be more even in flow and more unchecked in quantity. 
I have stated above that in the case of our hardy 
fruit-trees trained to walls or espaliers, it is dangerous 
to shorten the lateral branches, as this induces the 
production of too many woody twigs; this rule ap- 
plies in a general way to all trees, but is less to be 
regarded in the case of pyramids, standards, A-c. aa 
attention has in these latter to be paid to the acqui- 
sition of the proper form, when some shortening of 
the lateral branches is inevitable ; but this shortening 
partakes usually only of a slight character. But 
where shoots which are nipped or cut off low down 
as in the vigorous green tertiary shoots formed in 
summer, are liable to break out again very shortly, 
and perhaps with as great vigour as before, it ia 
advisable, though involving a little more time and 
labour, not to remove the shoots at all, but to twist 
them with the finger and thumb at a point near 
the base so as to leave them still attached and hang- 
ing from the injured portion. In this way they for 
a time draw a portion of the sup, which prevents 
the buds below from bursting fortu, and yet doea 
not detract to any appreciable extent from the sup- 
ply of sap to the fruit spurs on the mo her branch. 
These hanging twigs at length gradually wither up| 
when they can bo easily pulled of. If, however, the 
nipping of those green twigs takes place towards 
the end of the summer, say at tho end of July or 
August, the likelihood of their again shooting out 
will not be so grcttt (except ia a wet season/, for 
