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APPENDIX. 



trees in the open air, the soil has, by the spring, 

 parted with the heat stored therein, and become 

 colder than the sunny atmosphere enveloping the 

 leaves. Evaporation takes place in the young and 

 tender tissue, without a correspondent supply from 

 the roots ; then the young leaves collapse and curl 

 up, and the tender shoots, suddenly arrested in 

 their progress, swell and grow unshapely. In cold 

 and undrained soils this causes much injury to the 

 tree, and much requires to be cut away. 



Mildew, a minute fungus or vegetable parasite, 

 often produces considerable injury to the young 

 shoots by its roots piercing the tender epidermis, 

 and so blocking up the stomata or openings which 

 communicate with the interior of the branch. 

 Peculiar states of the atmosphere favour the 

 development of these fungi, and certain varieties 

 are well known to be more liable to their attacks 

 than others. The parts affected should be wiped, 

 and then dusted with flowers of sulphur, which 

 absorb the evil. A little oil paint is also good. 

 Insects are, however, a more severe trial to the 

 welfare of the trees. 



The Scale is one of these; it preys on the juices 

 of the stems and branches. The body of the female 

 is wingless, and covers a multitude of eggs under 

 its shield-like form. The male insect is a tiny 

 creature, much smaller than the female, and has a 



