June 27, 1908. 
THE GARDENING WORLD 
435 
be avoided as it flowers chiefly at the ends of 
the branches. March would be a good time 
to plant it or the first fortni-ght in No¬ 
vember. 
CHRYSANTHEMUMS. 
2971. Leaves Infested with Maggots, 
I enclose a Chrysanthemum leaf infested 
with a maggot. Can you tell me the 'cause 
and remedy of this complaint? (F. Smith, 
Essex.) 
The leaves you sent us were tunnelled by 
the Chrysanthemum leaf miner (Phytomyza 
nigricornis), a small black fly which lays 
its eggs on the leaves and the grub pene¬ 
trates through the tissues between the two 
surfaces. There are several broods in the 
season, so that the earlier you begin taking 
remedy the less trouble you will get. The 
very worst of the leaves may be picked off 
and burned, but if.there are only one or 
two small tunnels you should look on the 
under surface of the leaf and you will find 
the situation of the grub. Squeeze this be¬ 
tween the finger and the thumb and you will 
get no further trouble from that. Keep an 
outlook all through the season and repeat 
these operations. You could also syringe the 
leaves with strong-smelling tobacco water to 
prevent the mother flies from laying their 
eggs upon the leaves. As a rule, it does not 
do much damage to the autumn-flowering 
Chrysanthemum, provided you take precau¬ 
tion to destroy the maggots in the early part 
of the season. By pinching the grub you 
can retain the leaves upon the plants. 
FRUIT. 
297 2. How to Make Strawberries swell. 
I have about half-an-acre of Strawberries 
in rows, one plot being three years old. They 
are beginning to set. Would it be advisable 
to put on artificial manures to make them 
swell, and if so, what kind is the best for 
that purpose? (J. T., Ayrshire.) 
In the way of artificial manures you 
should apply nitrate of soda in water at the 
rate of ^ oz. to the square yard, or you could 
water the ground with some of the prepared 
and advertised manures, which are more 
general manures than nitrate. Either of 
these might have been applied with advan¬ 
tage early in May. The season is now so 
advanced that the quickest way to get the 
use of the manures would be to use it in 
water as stated. At the same time you can 
help the berries to swell by covering the 
1 ground with a good coating of litter or 
straw, so as to keep the berries off the ground 
and also keep in the moisture. Should the 
weather prove dry a good watering on the 
top of the mulching would be very effective. 
2973. Pear Branches Dying. 
I enclose a portion of the branch of a 
Pear tree of which several branches on one 
tree only have gone like it the last week. 
Can you tell me the cause, please, and, if 
any, the remedy? (A. E. G., Lancs.) 
We carefully inspected the specimen sent 
us, using the microscope, but all we found 
was not likely to be the cause of the death 
of the shoot. There were one or two cater¬ 
pillars amongst the dry leaves and a fungus 
on a dead portion at the base of a spur, 
but the injury in this latter case was so local 
that it could not account for the death of 
the branches. The wood and bark was 
healthy over the shoot generally, and merely 
drying up and becoming shrivelled. A cause 
should therefore be sought for elsewhere, say 
at the base of the dead portion. The branches 
might possibly be cankered there. Some 
people attribute the sudden dying of 
branches in this way to bacteria, though, 
perhaps, without reasonable grounds. Your 
best plan under the circumstances would be 
to cut away and burn the dead portions as a 
preventive in case there might be disease 
lower down the branch than the portion you 
sent us. 
2974. Pruning Apple and Plum Trees. 
Will you kindly tell me in your next what 
and,how much to prune my trees. I have 
one Plum and one Apple, standards, one 
Apple and one Pear bush. They have all 
flowered,, but very little fruit is on them, and 
I think it must be my bad pruning last year. 
I only summer-pruned them, not knowing 
what or how to winter-prune them. If you 
will help me you will greatly oblige. (A 
Learner, Middlesex.) 
After the head of a standard Apple is 
well formed it does not require much prun¬ 
ing in the proper sense of the term. If any 
part of the tree gets crowded with branches' 
it would be well to thin out some of them 
removing the weakest and most useless wood. 
If you do this in September while the leaves 
are still upon them you will see where the 
crowding is, if any. In the case 
of Apple and Pear bushes the summer 
pruning you should give them would 
be merely to shorten back side shoots coming 
in places where you should have spurs. It 
consists in cutting them back within three 
or four leaves of the base. Then in the 
winter time, or after the leaves are off, the 
shortened shoots should be still further shor¬ 
tened to one good eye to encourage them to 
develop fruiting spurs. The leaders should 
not be touched in the summer time, but al¬ 
lowed to grow as they' will. Then in winter 
the best plan is to cut back the leaders about 
half their length, except in the case of those 
varieties which flower most at the end of 
the shoots. Irish Peach behaves in this way, 
and if you would have a full crop the shoots 
must be left at full length on that and other 
Apples of similar behaviour. The Plum 
should, of course, be pruned much in the 
same way as Apples and Pears as it bears 
on spurs. When once the head of a stan¬ 
dard is formed very little pruning is neces¬ 
sary bey'ond thinning out some of the 
branches where they are crowded. This can 
be dene while the leaves are still upon them 
in September. The absence of fruit may be 
largely due to late frosts. 
GARDEN ENEMIES. 
2975- Grubs Eating Plants in Garden. 
I enclose a box containing grubs. They 
eat all the plants in our garden here. From 
enquiries they only seem to have been a 
plague this year and exist over south Dorset, 
at Weymouth, Dorchester, Bridport, and 
Portland. Locally they are called leather 
jackets and are said to be the larvae of the 
daddy-long-legs. I shall be much obliged 
if you would tell me what they are and 
whether they turn into a chrysalis. Also if 
you could tell me of any means of getting 
rid of them. (W. H. O., Dorset.) 
The grubs you sent were not leather 
jackets, as they are the larvae of daddy- 
long-legs (Tipula oleracea),, although we 
have heard this name given to them before. 
The specimens jmu sent us are the grubs of 
the heart and dart moth jAgrotis exclama- 
tionis), one of the Noctuina or night-flying 
moths. They live in the ground just under 
the surface and frequently under clods, stones 
and other means of shelter, and come out at 
night when they become mischievous. For this 
reason they are termed ground caterpillars. 
After they are full fed they turn into a rust- 
coloured chrysalis in the soil, where they 
lie until next spring or summer. They are 
not by any means confined to the county of 
Dorset, but are a common plague through tl e 
length of Britain, and some years are mu oil 
more numerous and destructive than in 
others. The reason why they are so destruc¬ 
tive is that they feed for a little upon one 
plant, then crawl off to another and commit 
the- same carnage. The plants, therefore, die 
because they are separated from the root or 
nearly so. One good precaution to take is to 
keep the ground clear of weeds whether in 
crop or not. Garden ground and fields are 
often neglected and allowed to become weedy 
in autumn and winter for the simple reason 
that there is no crop there. It is a mistake, 
however, to allow weeds to grow even during 
those periods, as it furnishes food for these 
ground caterpillars, for slugs and snails. 
The ground should be lightly dug over if it 
is impossible to keep it clean by means of 
the hoe when lying idle. When there is no 
crop on the ground you can also apply gas 
water, which kills the grubs. Soot is also 
employed for the same purpose, and in the 
case of Cabbages, Cauliflowers and other 
plants of that kind you can lay a band of 
soot round the stem of the plant and then 
earth them up. If the stems have been cut 
below this they will root into the soil afresh, 
and you can thus secure a crop. It would 
be well worth your while to try some of 
those more recent remedies which are de¬ 
structive to insect life, grubs, maggots and 
all the tribe of them. We refer to “ Va- 
porite,” “ Kilogrub ” and “ Alphol,” which 
you may see advertised in our pages. Dig 
the material into the infested ground, if 
the plants are far enough apart to admit of 
it. Good cultivation and the application of 
those remedies should clear your ground, 
after which, when in good condition, you 
may not have any more trouble for many 
vears. 
297 6. Apple Duke of Devonshire. 
Accept my best thanks for your replies to 
my previous questions. May I trouble you, 
however, in regard to the enclosed leaves 
cf Apple trees ? The first contains four 
leaves from Duke of Devonshire Apple. 
Please state nature of disease, if any, and 
remedy. (E. J. E., Essex.) 
The leaves of this Apple you sent us are 
swarming with the eggs of red spider. The 
tree must have been attacked at an early 
period, and the explanation is possibly that 
the tree is in an unusually dry position. The 
direct remedy is to thoroughly syringe the 
tree;, aiming principally at the under side 
of the leaves with strong soapsuds, which 
will be more effective than soap alone. See 
whether the ground is very dry, and, if so, 
give the tree a good watering now and again 
in dry weather. 
2977. Apple Lord Suffieid. 
I send three leaves from Lord Suffieid 
Apple Please state disease and remedy. 
(E. J. E., Essex.) 
The leaves you sent show that they are 
affected with the Australian shot-hole fungus 
(Phyllosticta prunicola). It resembles the 
ordinary shot-hole fungus, but is not quite 
the same. Most of the little bags or nests 
of spores had fallen out of the specimens 
you sent us. The remedy now is to pick up 
all fallen leaves and also to pick off those 
still on the trees showing traces of the fun¬ 
gus and to burn them. Next spring when 
the leaves are expanding spray the tree with 
a dilute solution of Bordeaux mixture. At 
this season it should not be strong, but be 
well diluted with water, otherwise the young 
leaves might be damaged. The disease also 
attacks, branches, and if you find evidence 
of disease upon any of them, those shoots 
should be cut off and burned, as it lives 
through the winter, commencing a fresh at¬ 
tack noon the leaves in spring. L T nless the 
spots are ’ l, ery numerous the fungus is not 
usually very destructive. 
2978. Caterpillars on Apple Trees. 
1 send you a spur from an Apple tree. 
Please state the remedy and name the cater- 
