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mould, etc. are required in order to maintain soil 
fertility. Well rotted cattle manure is the best 
form of organic manure for vegetable cultivation. 
The judicious planting of successive crops, in rota- 
tion, is of considerable importance. A rotation of 
crops is resorted to in ordinary practice in conse- 
quence of the economy of manure and variation 
of root growth which result from this practice. 
Certain crops are subject to special diseases, and 
the eradication of such diseases is often effected by 
the introduction of other types of crops. Plants of 
the same order should not follow each other. Deep 
and shallow rooted crops should, as far as possible, 
be grown in succession. A leguminous plant should 
be included in the rotation. The source and storage 
of seeds must receive careful attention. It is of 
primary importance in the combating of insect and 
fungoid attacks to ensure that the plant is main- 
tained in a vigorous condition by good cultivation. 
When practicable, hand picking of insects should 
be resorted to; this applies in particular to the 
numerous species of caterpillars which feed on 
stems and leaves. Several fungoid diseases do 
considerable damage and are kept in check prefer- 
ably by strict plant sanitation. Good cultivation 
and drainage, judicious manuring, rotation of crops, 
isolation of infected areas, destruction of diseased 
pJants or tissues, freedom from wounds, artificial 
watering and careful pruning when necessary, are 
factors which tend to reduce the possibilities of 
attack and spread of disease. 
There are numerous factors which require to be 
considered in making a selection of vegetables for 
the garden. In small gardens a selection of edible 
leaf and stem vegetables should be grown as these 
