Reports to the Board of Agriculture. 25 



These small red spots are not scales nor the stage (jf any insect, 

 the qnince having red bark spots. 



It is important to notice whether we have scale on the tree or 

 whether the markings are normal plant structures. Scales are often 

 very harmfid in this country and should be checked before they get 

 the upper liand of the tree and sap its vitality. 



Three washes may be used for scale insects : — 



1. Paraffin emulsion. 



2. Eesin wash. 



3. Caustic alkali wash. 



The first (paraffin emulsion) is chiefly of use when the young 

 scale insects are emerging from beneath the scales ; observations 

 personally by the grov/er must be made, as the times of hatching vary 

 very much. 



Caustic alkali wash is the most beneficial to use (^•ide article in 

 the September number of the Board " Journal"). 



Fumigation with hydrocyanic acid gas is the best scale remedy, 

 but is difficult to apply to large trees. Should this be employed, full 

 information will always be sent from this Department. 



Winter washing with caustic alkali wash is strongly advised. 



Life-history of Scales (Coccidcc.) 



The eggs of the Coccidie are found under the scales ; the young 

 scales are minute, active, six-legged insects with projecting antenme 

 (" horns ") and often hair-like processes. They can only be seen 

 with a strong magnifying power. Scales (Coccidre) are provided 

 with a long piercing mouth, which the larvse thrust into the bark, 

 leaf or fruit. The larvte then degenerate, and by degrees form over the 

 body a scaly covering — beneath which you find the mature female, 

 which is legless ; the male scale insect is rare, and imlike the female 

 is active, having a pair of wings. Scale insects on trees in the open 

 pass the ^vinter in Great Britain mostly in the egg stage beneath the 

 scales, a few as immature females. 



Scale Insects on Plum Trees. 



Plum trees sometimes sufter from scales. The Oyster-Shell 

 Bark Louse (Asjoidiotus ostrecqformis, Cmtis) is found on plum. A 

 brown Lecanium has also been found, but was not identified. 



The Japanese Fruit Scale {Diaspis amygdali) also occurs on plum, 

 and thus care should be taken to examine all Japanese cherries that 



