GREENHOUSE PESTS 123 



The fungus appears as a delicate white powder in patches 

 on the tops of the leaves and also on young shoots and 

 fruit. Spraying with potassium sulphide should be 

 repeated as occasion requires and all diseased leaves and 

 fruit collected and burnt. Dust with flowers of sulphur 

 also. (See Plate 25.) 



Then there is White Rot, which eats its way into 

 branches and fruit. This fungus never attacks foliage. 

 Bordeaux mixture will effectually deal with it, as many 

 folks have noticed in the wine-growing districts of France 

 and Italy, where bunches of grapes may be seen coated 

 with the blue " verdigris " which to the uninitiated looks at 

 first as though the remedy were really the disease. It is 

 washed off quite easily. 



The greenhouse is capable of providing us with the 

 much-prized green figs in England, whilst the pine-apple 

 itself is the perquisite of those who can afford to spend a 

 sovereign to get half-a-crown. Pines of course are also 

 grown in special pits on a hot-bed, but they are very 

 costly to produce. Both crops are subject to Mealy Bug 

 and White Scale, which can be met with kerosene emul- 

 sion, done before fruiting time. The above remarks also 

 apply to fruit trees such as peaches, apricots, oranges, 

 mulberries, nectarines, etc. On all these trees a lookout 

 should be kept for Tortrix moths as well as for scale and 

 aphis. The Figure of Eight Moth, described in the last 

 chapter, is also likely to turn up, and I give a drawing 

 of its larva for identification on Plate 26.) 



Next we come to cucumbers. Here are Aphis again, 

 as well as Red Spider. Thrips also occur, all of which 

 have been treated of. Woodlice also give trouble unless 

 rigorously routed out, and it is hardly necessary to say any 

 more about that. 



The Canker {M. citrullina) attacks cucumbers, melons 

 and greenhouse tomatoes. This fungus betrays itself by 

 a greyish white sickly appearance of the stems of the 

 plants, which may often be killed outright. It is one of 



