ON VEGETABLE CULTURE. I065 



methods suggested in the Chapter "On Pests Generally." A 

 Mildew also asserts itself upon the leaves of Lettuce, both forced 

 and grown outside, though chiefly upon the former. It is a 

 species of Peronospora, and causes the plant to turn sickly and 

 die. A well-ventilated house and a not too moist atmosphere 

 will tend to keep it at bay. 



Mushrooms. 



These delicious vegetables, or fungi, are always appreciated, 

 and when manure from horses fed on dry food can be 

 obtained in quantity there is little trouble in growing Mush- 

 rooms all the year round. Manure from horses fed on roots, 

 or receiving medicine, is of no use. Mushrooms absolutely 

 refusing to grow in such droppings. It should be collected every 

 morning, or oftener, and placed about ift. deep on the floor of 

 an open shed, free from drip or wet, turning the droppings every 

 morning, and working out all the long straw. This process of 

 turning should be repeated daily, until there is sufficient manure 

 to make a bed 

 — large or small, 

 according to re- 

 quirements ; then 

 the whole should 

 be thrown into 

 a heap to heat 

 thoroughly, and 

 to eradicate any 

 rankness. The 

 heap ought to be 

 turned thoroughly 

 and well mixed 

 daily for a few 

 days or a week ; 

 it will then be in 

 good condition to 

 make up into a 

 bed, say, ift. deep, 

 which should be beaten firm. This bed will generate consider- 

 able heat, but when the heat has fallen to 75deg. or 8odeg. it 

 will be ready for spawning. 



The spawn should be broken up into pieces about the size of 

 a hen's egg, and inserted 2in. deep and about ift. apart over 

 the whole of the bed, making the droppings firm again over the 

 spawn. A coating of good fibrous loam 2in, deep, spread evenly 

 over the bed and gently pressed with the back of a spade, will 

 complete operations, taking care that the soil is neither too w^t 

 nor too dry, as no watering of the bed — unless it becomes very 

 dry — should be done until the Mushrooms appear, which usually 



Fig. 683. — Mushrooms Grown in Pans. 



