94 TRACE ELEMENT DEFICIENCY 



copper sulphate, either to the soil or by injection, was effective 

 in bringing about arrest of the disease and recovery of the trees. 

 The copper content of leaves from healthy trees varied from 5-5 

 to 12 p. p.m. of the dry weight, whereas in leaves from affected 

 shoots the content varied from 1 to 3-6 p. p.m. of the dry weight. 

 These values agree well with those found by Anderssen for the 

 leaves of Kelsey plum trees, and by Oserkowsky and Thomas 

 for the leaves of Bartlett pear. 



However, Haas and Quayle made many determinations of the 

 copper content of orange and lemon leaves and fruits, including 

 samples from normal and exanthematic trees and from affected 

 trees that had recovered as a result of the application of copper 

 sulphate, and concluded that so much variation exists in the 

 copper content of the leaves and fruits of trees from different 

 localities and sites that it is not possible to decide from a 

 knowledge of the copper content whether trees are suffering from 

 a deficiency of that element or not. It may be said, however, 

 that the values they obtained are of the same order as those 

 already noted here. Thus the copper content of mature healthy 

 orange leaves from untreated trees varied from about 7 to 

 15 p. p.m. of the dry weight, the corresponding values for the 

 leaves of lemon being between 4 and 13 p.p.m. For two grape- 

 fruit leaves the values were 6-4 and 7-38 p.p.m. The fruit appears 

 to contain much less copper calculated on a dry -weight basis, the 

 content of the element in oranges and lemons ranging respec- 

 tively from roughly 2 to 4 and 3 to 5 p.p.m. in these fruits. 



Reclamation Disease. A disease attributed to copper 

 deficiency, which affects oats and other cereals, beet and legu- 

 minous crop plants, occurs on reclaimed heath and moorland 

 soils in Denmark, Holland and other parts of Europe. In affected 

 plants the tips of the leaves become chlorotic, and in cereals 

 this is followed by a failure of the plants to set seed. This disease, 

 known as reclamation disease or yellow -tip, was originally 

 attributed to the toxic action of a constituent of peat, but 

 Sjollema (1933) in Holland showed that the disease could be 

 cured by the addition of copper sulphate to the soil, and that the 

 content of copper in wheat, rye and hay grasses was raised by 

 this soil treatment. Later, Gram (1936) obtained similar results 

 with barley and oats in Denmark, and Undenas (1937) with oats 

 in Sweden, while in 1938 Piper found the disease affecting 



