430 Destructiofi of fhe'Meoly Bug cmd Scale, 



My present mode of treatment teaches me that bottom heat 

 is not indispensable to the growth of the pine-apple, as I have 

 kept some of them for three or four years in the same bed, 

 where, towards the last, the heat of the dung and tan was not 

 greater than that of the atmosphere or the natural soil, with- 

 out preventing my plants being adorned with the most beautiful 

 fruit. It has also shown me that ripe fruit may be obtained 

 by growing without pots in pits, as first described, throughout 

 the whole year, as I can prove by regular tables kept for the 

 last five years, showing that I furnished ripe fruit from these 

 pits every month in the year during that period. 



By the above communication, I hope to have fulfilled your 

 desire, and have the honour to be, Sir, &c. 



Joseph Lang. 



Nymphenburg, Nov. 4. 1828. 



Art. XIX. On the Destruction of the Mealy Bug and Scale on 

 Pine Plants. By Mr. James Dall. 



Sir, 



As none of your correspondents has taken notice of the 

 insects that are so destructive to pine-apple plants, I beg leave 

 to send you a statement of the method adopted by me for 

 their destruction ; which effectually killed every mealy bug 

 and scale that was on my pines. 



When I came to this place in 1808, I found the pines 

 covered with the mealy bug and white scale, and I had imme- 

 diate recourse to a recipe of an old acquaintance of mine, Mr. 

 W. Nicol, with this difference, that I used 4 lb. soap, where he 

 recommends only 2 lb. In that case my mixture consisted of 

 4 lb. soft soap, 2 lb. flower of sulphur, 1 lb. leaf tobacco, and 

 2 oz. nux vomica boiled in 8 gallons of rain water. After 

 shaking the plants out of the pots, and trimming their roots, 

 I washed them well with this mixture. I also had the wood- 

 work and glass, inside of the houses and pits, washed with the 

 same mixture, and the walls and flues washed with a mixture 

 of lime and sulphur. 



The tan in the bark beds I had sifted, and fiesh tan added 

 to make good the dust taken away ; the whole, old and new, 

 being well mixed togethej', the plants were repotted and re- 

 plunged, and attended to as usual. 



From that time I was no more troubled with the mealy bug, 

 but the scale was not entirely destroyed : for, towards the end 



