188 Mode of destroying the White Scale 



Circumstances made it unavoidable for me to perform the ope- 

 ration at the period I have mentioned ; nevertheless, I think, with 

 Mr. Wilson, that the usual time of spring-shifting is decidedly 

 preferable : because, at that season, the plants begin to push new- 

 leaves almost immediately, and sooner grow out of their murky 

 covering ; while, for three or foiu' months in winter, they make 

 very little progress ; and the leaves, having their pores partially 

 choked by the powder, are in some measure rendered incapable 

 of performing their functions : and this, to a certain extent, must 

 be injurious to the constitution of the plants. If the dressed 

 plants stand near the glass in pits or low houses, they must be 

 carefully shaded from powerful sunshine ; for the direct rays, 

 acting upon the leaves, produce an effect similar to burning. In 

 my case, no such precaution was necessary ; as the plants stood 

 at a great distance from the roof of the house, and tVie vines 

 afforded no inconsiderable shade. Unlike the mealy bug, the 

 white scale never attacks the roots, nor buries itself in the soil, 

 but wholly confines its ravages to the leaves, stem, and fruit: 

 therefore, if more convenient, the plants can be quite as effec- 

 tually dressed without being taken out of the pots, provided that 

 enough of soil is removed to allow a free examination of the 

 lower parts of the leaves, where the insects are generally most 

 numerous. 



If the brief directions I have laid down be strictly and per- 

 severingly followed, the result will be the complete destruction 

 of this most injurious enemy of the pine-apple : in fact, in this 

 case, we can command success if we deserve it. 



A few observations upon the natural history of the white scale, 

 of which so very little seems to be known, may not be out of 

 place here; but they are offered rather with a view of calling the 

 attention of others to this subject, than of enlightening the dark- 

 ness in which it is involved. On referring to the fourth edition 

 of the Encyclopedia of Gardenings I find it said that the white 

 mealy crimson-tinged insect " is, by some, thought to be the 

 same as the white scale." How such a mistake could have ori- 

 ginated, I cannot conceive ; for, in point of fact, a bog and an 

 elephant resemble each other just as much as the white scale and 

 the mealy bug. Happily, my ac({uaintance with the latter is very 

 limited ; but I know enough of the former to enable me decidedly 

 to deny their identity, having frequently witnessed pine-plants 

 plentifully stocked with white scale, upon which not a single 

 mealy bug was ever seen. If a white scale of the largest size be 

 attentively examined, after having been detached from the plant, 

 it will be found to cover a multitude of very minute brownish 

 grains ; and these, undoubtedly, are the embryo insects. When 

 dressing the plants, I have found myriads of these little gi*ains 

 firmly adhering to them, especially in the small furrows so 



