VEGETABLE GABDEN 



1113 



Group I. — Ceucifeeous Crops 



Diseases of Cruciferous Crops. — Many 

 plants, both wild and cultivated, belonging 

 to the Crucifer Order (see p. 201) are sub- 

 ject to a virulent disease known as ' Club- 

 root ' or ' Fingers and Toes.' Turnips 

 especially, and Cabbages, suffer most 

 severely from this disease, but other kinds 

 suffer from it also. It is caused by a 

 fungus called PlasmocUopTiora hrassicce, 

 which penetrates the roots and causes 

 them to swell up abnormally into a 

 roundish or spindle-shaped mass, often 

 more or less spreading like fingers, hence 

 one of the common names. The root 

 cells are very much swollen by the action 

 of the fungus, and when Jirst attacked 

 their contents are of a slimy yellowish 

 colour. During the autumn and winter 

 months the fungus is maturing, and by 

 the spring its numerous spores' contents 

 are shed, and creep about the damp soil 

 by means of motile hairs. In due course 

 each one completely unites or fuses with 

 some other and forms a larger bodj'. In 

 this state they are ripe for vegetating on 

 the roots of any Cruciferous plant, whether 

 weeds or not, and set up the disease in 

 them. 



Remedies. — It is often a good plan to 

 dig the green stems and leaves of plants 

 into the soil as a manure, especially plants 

 belonging to the Pea and Bean Order (Le- 

 guminossa, see p. 322). That practice, how- 

 ever, cannot be recommended with any 

 plants of the Cabbage family (Cruciferse, 

 see p. 201) owing to the above disease. It 

 is therefore a mistake to allow the stumps 

 and roots of Cabbages, Brussels Sprouts, 

 Broccoli and the other crops described 

 firom p. 1114 to p. 1123 to lie rotting on the 

 soil, or to dig them in as manure, as they 

 may contain the germs of the disease. 

 They are best burned, and there will be 

 no danger in spreading the ashes over the 

 soil. This may be regarded more as a 

 preventive perhaps than as an actual 

 remedy, but burning will effectively de- 

 stroy any Clubroot fungus that may be in 

 the roots. 



A second remedy or preventive con- 

 sists in the r'otation of crops (p. 1104). 

 Never grow plants of the Cabbage family 

 on the same ground two years running 

 if it can possibly be avoided, even if Club- 

 root does not exist. Where Clubroot has 



appeared once. Cruciferous crops should 

 not be grown for years, and all Cruciferous 

 weeds like Charlock or Wild Mustard, 

 Shepherd's Purse, Garlic Mustard &c. 

 should be stamped out, as their roots 

 serve as more or less welcome hosts for 

 the fungus. Treatment with lime, soot 

 &c. is very little use agaiast the dis- 

 ease, although they benefit the soil, but 

 boiling water would probably be highly 

 effective. 



Anbury or Ambury is another disease 

 common to Cruciferous plants, especially 

 Turnips and Cabbages. It is brought 

 about by small Cabbage Gall Weevils 

 called Ceutorrhyiichus suUcolUs which 

 form galls on the roots. These galls 

 harbour the small white grubs of the 

 Weevil, and become as large as spUt peas. 

 Little mischief seems to result from their 

 attacks, but whenever galled roots are 

 noticeable they should be picked off and 

 burned so as to destroy the grubs. When 

 transplanting Cabbages, Brussels Sprouts 

 &o. some gardeners dip the roots into 

 a lather or puddle of clay and soot and 

 lime as a preventive. The remedies men- 

 tioned above under Clubroot are on the 

 whole the safest and best. 



Other pests of Cruciferous crops, be- 

 sides those already mentioned under Tur- 

 nip (p. 1119), are the whitish cylindrical 

 maggots of the Cabbage Fly (Anthomyia 

 brassicce). These attack both stem and 

 root and cause the leaves to ' flag ' or 

 wilt and turn yellow. The infested 

 plants are best x'emoved and bm-ned. At 

 the time of planting, a good dressing of 

 lime and soot around the young plants 

 will check their ravages. 



The Large White Cabbage Caterpillar 

 [Pieris brassicce), and the Small White 

 one (P. rapes), and the caterpillars of the 

 Cabbage Moth (Mamestra brassicce) do 

 a good deal of mischief to the leaves and 

 heads of Cabbages &c., often spoiling a 

 whole crop when measures are not taken 

 to prevent them. 



Hand-picking and treading under foot 

 is an effective but tedious cure. A good 

 sprinkling with Hme and soot early in the 

 morning when the plants are wet with 

 dew will be found useful. Soapy water is 

 also a good remedy. See also Enemies 

 &c. of the Turnip (p. 1120). 



