ON THE CULTURE 



of their roots at the time of dressing ; but ex- 

 perienced gardeners prefer that method to re- 

 moving them with balls of earth at their roots, at 

 the time of shifting them in the spring. I have 

 frequently tried both methods, and always found 

 that the plants removed with balls of earth at their 

 roots had a little advantage at first ; but, in the 

 course of the summer, the plants with fresh mould 

 entire always made the greatest progress. 



Having thus described my method of destroying 

 these most troublesome insects, and gone through 

 the whole process minutely in all its parts, I shall 

 now beg leave to make a few necessary observ- 

 ations. 



First, Was the method of putting quicksilver in 

 the cistern, which contains the water for the use 

 of the hot-house, to be depended upon as effectual, 

 there would be no other way of destroying these 

 insects so cheap and easy ; that business would 

 be done in the common course of watering the 

 plants, and there is a probability of its being suc- 

 cessful : for it is evident that the insects, whether 

 at the roots or upon the leaves of the Pine, subsist 

 on the juices of the plants ; and it may be possible 

 for the plants to imbibe a certain quality from the 

 quicksilver sufficient for the above purpose. How- 

 ever, as I verily believe that the insects were to- 

 tally destroyed here before I tried the above 

 method, I cannot say any thing in regard to its 

 efficacy. Yet it would be well if a trial of this 

 sort were made -> in which case I would recommend, 



