IX PESTS 181 



At such a time — the first appearance — the time 

 for checking a pest — ^I quite beHeve that, as in the 

 case of aphides, there is nothing to beat the human 

 finger and thumb. With them take a pinch of 

 sulphur, and gently rub the affected part on both 

 sides of the leaf. Sulphur is death to all fungoid 

 life, but is rendered more efficacious if the mycelium 

 is thus broken and wounded : just as there would be 

 much difference between poison merely sprinkled on 

 the human skin or rubbed into an open wound. 



When the pest is advanced and whole plants 

 covered with readily disturbed fresh spores have to 

 be dealt with, one of the now advertised remedies, 

 applied by spraying-pump or syringe, so adjusted as 

 to reach the under as well as the upper sides of the 

 foliage, must be employed. For the plant, so to speak, 

 of the mildew very soon springs from the spawn, and 

 fresh spores are ready in a wonderfully short time 

 to be borne by the wind to other leaves. 



On touching a shoot infected with mildew on the 

 roof of a greenhouse or anywhere where there is 

 plenty of light underneath, quite a little shower of 

 dust or mildew seed may be seen to fall, Nothing 

 need be feared from those that fall to the ground : 

 they are very short-lived, and cannot stand much of 

 heat or cold, dryness or moisture. Their strength is 

 in their appalling numbers, and their chances of 

 falling on another Eose leaf depend entirely upon 

 currents of air. 



With the first touch of cold weather in Autumn, 

 mildew, as we know it in its summer form, dis- 

 appears and is seen no more that season, only dark 

 unhealthy-looking marks on the shoots showing 

 where the pest had spread from the leaves to the 



