THE OARDBN1NO WORLD. 
551 
July 2, 1904- 
or fungus, but is a mere succulent outgrowth from the surface 
of the leaves. 
An Abutilon going Green. 
We have a good-sized plant of Abutilon vexillarium, which 
was at one time a very handsome specimen, but the plant is 
getting greener every year. Will you say what is the cause of 
this, and if it can be made to produce variegated leaves only l 
(Abutilon.) 
Possibly over-feeding or too rich a soil may have caused the 
plant to return to its original green state. The plant is simply 
making an effort to overcome the yellow markings which are no 
advantage to it. In other words, the plant is regaining its 
natural vigour. From the cultivator’s point of view this is not 
desirable, and if a large portion of the plant is now green it 
would be better to commence again with young plants, by 
taking off the variegated portions and inserting them as cut¬ 
tings. When the plants are rooted and making headway, it may 
happen again that shoots will be developed bearing green leaves, 
but if you remove these in time the plant will then devote all 
its energy to the development of the variegated portions. The 
plant would ultimately become green for the simple reason that 
green leaves always assist the production of stronger branches 
than those produced by variegated leaves. The larger the green 
surface the more work can be done by the leaves, and the larger 
the variegated portions the weaker will be the branches pro¬ 
duced by them. 
Wallflowers Stunted. 
A bed of Wallflowers here sown in the open ground showed 
good growth for some time, but as soon as the dry weather set 
in they looked stunted and flagging. On opening up the soil 
around some of the plants, I found them swollen at the roots. 
Could you tell me if this is due to some insect, or is it a new 
disease? (W. H.) 
There can be little doubt that your seedling Wallflowers have 
been attacked by the same fungus which attacks Cabbages? Cauli¬ 
flowers, and other members of the tribe. It is not confined to 
the Cabbage tribe, but is found on the roots of other members 
of the same family. We can only imagine that you have sown 
the Wallflowers on ground which has been planted at some time 
or other recently with some member of the Cabbage tribe. In 
any case, the ground has become infested with the fungus 
(Plasmodiophora Brassicae). We are afraid you will be unable 
to save the plants unless some of them are still healthy and 
unattacked. Your best plan will be to dig them up, examining 
each carefully to see that there are no swellings upon the roots, 
and transplant them into a bed of fresh soil in another part 
of the garden. By that means you may be able to save those 
that are still healthy. It will be advisable to give the soil in 
which you are about to plant them a dressing of lime before 
digging it- In future, it will be well to sow Wallflowers in 
some situation well removed from any of the pieces of land 
utilised for the growth of the Cabbage and Turnip tribe. 
Digging and trenching such soil in the autumn, according to our 
experience, has been a good means of clearing the land in¬ 
fested by this fungus. 
Pears Swollen. 
When looking at a fine crop of pears on one of our trees here, 
I noticed some of them curiously swollen, and on cuttinlg one 
open I found it full of grubs- Can you tell me what they are, 
and if there is any remedy? (A. Caudwell.) 
No doubt they are the caterpillars of the Pear Midge 
(Diplosis pyrivora), but you should have sent us specimens. 
From your description, however, we think there can be little 
doubt that this is the insect that is giving you trouble, as it 
has been becoming more and more common within the last few 
years. Pick off all the fruit that you see having a lot of little 
swellings. Later in the season these fruits, if they continue 
to hang on until they get to some size, will become more or 
less discoloured on those sides which have been injured by the 
grubs inside. The chief thing you can do is to pick off all the 
injured fruits and burn them. You might also shake the tree, 
and if others are badly injured they will drop, and may be 
gathered up and burnt like the rest. The grubs have their 
origin in eggs that are laid by the female insect when the 
ossoms are just on the point of expansion. These hatch out, 
and proceed to feed upon the tissues of the Pear, thus setting 
up an irritation and causing the growth which you mention. 
you can possibly destroy all of the fruits that are injured 
m this way, very few will be able to pass through their changes 
an. reach the perfect stage to give you trouble next year. They 
pass into the pupa stage in the soil, and in cases where the 
P an ation of Pears is large and the insects very numerous, so 
t a rnany of them escape into the soil, it would be worth while 
s im off the top soil to the depth of 2 in. and burn it.' We 
think, however, that if you have never noticed them before, they 
cannot yet be very numerous, and you may be able to keep’them 
under by giving close attention to the matter as above directed. 
American Blight. 
Some of our young Apple trees are badly blighted with woolly 
aphis. I would consider it a favour if you would give me any 
remedy that would not damage the foliage, as the trees are 
making good growth. (J. W. D.) 
There are several remedies that might safely be employed in 
winter that would be more dangerous when the leaves are on 
the trees. No harm will result, however, from the use of soft 
soap or Gishurst Compound in the form of thick lather. It may 
be made quite strong if merely used to anoint those parts that 
are affected with the blight. Upon young trees it is not diffi¬ 
cult, as a rule, to reach the aphides, so that you can rub on the 
insecticide where you discern woolly aphis, using a painter’s 
half-worn brush for the purpose. If you can destroy the insects 
before they have time to form hiding places owing to growth 
ot the tree, there will be no difficulty in eradicating them. If 
allowed to feed on the branches all the summer, the chances are 
that the bark will split open along those sides which are injured 
by the insects, this being due to unequal growth of the branch 
brought about by the damage inflicted by the insects. Remember 
that work of this kind is always best to be taken in hand at 
once, before much damage has been inflicted and before the in¬ 
sects have had time to increase in numbers. If neglected for 
a season the trees attempt to heal the wounds by producing 
fresh growth, which grows over the wounded portions, thus 
forming hiding places for the insects in which they can nestle 
securely during the winter to commence work again in the spring. 
If boys are employed to do this, it will be well to impress upon 
them to do the work effectively. 
Chrysalides on Euonymus. 
I send you some chrysalides, which were hanging among the 
branches of Euonymus, some of the leaves of the bush being 
eaten. Please say if the caterpillars eat anything else besides 
Euonymus. (G. M.) 
The chrysalides you send are those of the Gooseberry Moth 
(Abraxas grossulariata). As you know, these are sometimes very 
troublesome to Gooseberries and several other plants. Cater¬ 
pillars are hatched in the autumn, and feed for a time upon the 
bushes, and then with the falling leaves they simply take shelter 
amongst the same at the foot of the bushes resting in- that condi¬ 
tion during the winter. With the expansion of the leaves in 
spring, they commence feeding again, devouring the leaves until 
they have reached their full size. After this they change into 
the pupa or chrysalis stage, which is hung up by a thread to the 
bushes on which the caterpillars fed, or on something else close 
at hand. They will certainly occur on other plants besides 
Gooseberries, but by destroying the caterpillars and pupae you 
may be able to keep them under. In our experience this is by 
no means so bad a pest as the caterpillars of the Gooseberry 
Sawfly. 
Cucumbers Damping Off. 
I am enclosing you some specimens of Cucumbers, and should 
be obliged if you can help me to account for the way they have 
gone off. I have been cutting since April, and have always 
suffered sometimes more, sometimes less, and although I have 
been growing Cucumbers for some years, I have never experi¬ 
enced the same trouble. One morning I cut off half a bushel 
of young and partly grown Cucumbers all affected in the same 
way. I have been advised to discontinue syringing, but with, 
as I expected, red spider as the result. I think more go off 
after a hot day than a dull one, and I ke?p the house well aired. 
I have always damped down and syringed freely, but I was 
strongly advised I overdid it. I tried first less syringing and 
then completely discontinuing it, but; the result is not satis¬ 
factory. (Novice.) 
The fruits you send us have every appearance of having been 
attacked by a fungus which evidently enters the fruit by the 
decaying flower. This being so, the stopping of syringing for 
a few days or weeks would not entirely eradicate the pest, as 
the house may be full of spores. AVe have observed damping 
like this continue to the end of the season after it once com¬ 
mences, as the atmosphere of the house must be full of spores. 
Syringing is only one thing, but if the atmosphere of the house 
is kept continually damp, with a low temperature, there is every 
chance that diseases of some kind or other will presently get 
a footing. You will have to make a fresh start after the^house 
has been cleared, by clearing out the soil and everything in 
the house, which should then be syringed in every corner and 
crevice so as to destroy insects and fungi. The glass and wood- 
