LARGE SCALE SAND CULTURE METHODS FOR 

 THE STUDY OF TRACE ELEMENT NUTRITION 



OF PLANTS 



hy E. J. Hewitt, Ph.D., B.Sc, 



Agricultural and Horticultural Research Station, Bristol University, 

 Long Ashton, Bristol 



The methods described here were specially designed to permit 

 the study of nutritional relations and particularly trace element de- 

 ficiencies of iron, manganese, boron and molybdenum in plants 

 when it is necessary to use a large scale, required either by the 

 scope of the experiment or by the size of the cultures themselves, 

 as when fruit trees are used. Special problems of technique arise 

 when large numbers of plants are to be grown simultaneously and 

 the materials available for use are often limited owing to scarcity, 

 cost or undesirable interaction in the experiment, but simple mate- 

 rials can often be suitably adapted or refined for such purposes. 

 In their simplest form they comprise clay flower pots with a cen- 

 tral drainage hole; a silica sand obtained from Leighton Buzzard 

 in Bedfordshire; rain water collected from the roof of the large 

 glasshouse used to shelter the plants and analytical reagent (A.R.) 

 grade nutrient salts; for certain purposes, for example, molybde- 

 num deficiency experiments, the clay pots and rain water are not 

 effective and must be replaced by pyrex glass containers and dis- 

 tilled water. Each of these materials will be considered in order 

 below. ^ 



Containers:— Ten inch clay pots are used for most experiments 

 wdth vegetables. Satisfactory results with deficiencies of iron, 

 manganese or boron and all major nutrient elements are obtained 

 if the clean dry pots are carefully painted with at least three coats 

 of a pure bitumen solution free from these elements. The bitu- 

 men paint prevents the plant roots from absorbing nutrients from 

 the clay which otherwise yields all the boron and calcium required 



1 The methods outlined in this paper have subsequently been extended to include 

 copper, zinc and molybdenum deficiencies, and fmrther adapted for large scale experi- 

 ments. Descriptions of these will appear in a Technical Communication of the 

 Commonwealth Bmeau of Horticulture and Plantation Crops, East Mailing, England, 

 entitled 'The Use of Sand and Water Culture Methods for Plant Nutrition' by E. J. 

 KLewitt (in preparation). 



