Reports to the Board of Agriculture. 1 8 1 
a quantity of liquid over trees or plants by means of an ordinary 
syringe. In the so-called “ washing or spraying,” the insecticides are 
sent out by means of special apparatus, which distribute the fluid in 
a fine mist or spray. 
The caustic alkali wash could not well be applied with a brush, 
and certainly not with a sponge. 
It might be applied with a garden syringe, but much of the 
liquid would be wasted ; proper spraying machines should be used. 
Canker Disease in Apple and Pear Trees.— The bark of apple 
and pear, sent by a correspondent from Studington, near Cheltenham, 
supposed to be insect damaged, shows no trace of any insect damage, 
nor insects. 
It presented all the typical symptoms of Canker Fungus (Nectria 
ditissima), described in certain stages in Leaflet No. 56. 
(The working of canker in varied ways is often taken to be insect 
damage, but when the latter cause harm the pests can be easily 
detected.) 
Thrips on Cucumbers. — A correspondent wrote asking for a 
remedy for Thrips in cucumbers. The following reply was sent : — 
Thrips on cucumbers may be destroyed in many ways. 
A common plan is simply to syringe with cold water. 
Quassia wash has been used with success and also fumigation 
with tobacco. 
I think that the pyrethrum wash is best, however. 
The pyrethrum should be quite fresh, as it soon loses its strength. 
Celery Fly (Acidia heraclei ). — The diseased Celery leaves sent 
by the Crown Trading Company, Limited, from Cottenham, near 
Cambridge, were found to be badly attacked by the Celery Fly 
(. Acidia heraclei). 
All necessary information is given in Leaflet No. 35. It has 
been very harmful in many districts this season. 
Cabbage and Cauliflower Maggot. — Two enquiries concerning 
the Cabbage Root Maggot have been received. A report on this 
pest is given on p. 67. 
One correspondent sent some Centipedes with them and various 
notes. 
There is of course no connection between the maggots and the 
centipedes, but it is very probable the centipedes are preying upon 
the grubs. 
