CLOVER. STEM EELAVORM. 



51 



Celery being a plant that naturally grows in wet places, 

 suffers from drought, and the Celery Fly thrives in dry 

 weather. For this reason it is desirable, where practicable, 

 to turn a good supply of water into the trenches from time to 

 time. This makes the manure at the roots available, and the 

 evaporation keeps a damp air round the plants very good for 

 growth. 



It is also of service to start with the garden-engine, or hose 

 from water-supply, or large-rosed watering-can, at one end of 

 the row, and send a good power of water strongly at the leaf- 

 age, going regularly forward from one end of the row to the 

 other. This clears off swarms of insect-vermin, which may 

 be seen preceding the operator down the row ; and if, whilst 

 the leafage is still moist, any dressing that may be known to 

 be serviceable is sprinkled over the leaves, it will adhere for a 

 while, and be very useful in keeping off attack. 



CLOVER. 



stem Eelworm. Tylenchus devastatrix, Kuhn. 



Stem Eehvorms {Tylcnclnis devastatrix) : anterior portion of female showing 

 mouth spear ; and embryo in egg ; all greatly magnified ; anterior portion mag. 

 440 times. From figures by Dr. J. Eitzema Bos. 



Clover "sickness" as it is termed, may arise from many 

 causes, such as unfavourable weather, or nature or condition 

 of soil being unsuitable to the plant ; or from attack of fungus 



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