Symptoms 



cabbages in damp, ill-drained places. Brown 

 spots are evident on the lower part of the stem, 

 which dies and decays. 



Boot. — Rootlets swollen in a spindle shape 

 much larger than normal ; whole plant often 

 sickly -looking ; root subsequently rots and sets 

 free spores of the fungus, Plasmodiophora 

 Brassicae, to infect succeeding crops of same 

 family. Keep down weeds belonging to cabbage 

 family (9) ; practise rotation of crops (8) ; lime 

 the soil thoroughly (12). This is club-root 

 and should be distinguished from cabbage gall 

 weevil, which produces little lumps on the 

 stems, each containing a small grub. 



Stem. — One-sided heads, or failure to form 

 heads, together with a dark ring seen in the 

 stem when cut across ; leaves, except veins, 

 yellow (at margins at first) ; veins brown or 

 black. Slugs and caterpillars spread the cause 

 of this disease, a bacterium, Pseudomonas 

 campestris. Practise rotation (8) ; remove 

 affected leaves and destroy affected plants by 

 fixe (3, 4). Seed should not be saved from 

 infected plants. [Black rot.J 



Foliage. — White rust and rot mould; see 

 Arabis. Destroy affected parts (3, 4) ; spray 

 (young plants only) with Bordeaux mixture 

 or liver of sulphur (7) ; keep down weeds 

 (9). 



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