452 EXPERIMENT STATION RECORD, [Vol.41 



The conclusion drawn by the author is that finger-and-toe in turnips can be 

 kept in check or entirely prevented by using lime in sufficient quantity to neu- 

 tralize all sourness and leave some excess of carbonate of lime in the soil. It 

 is not necessarj' to lengthen the rotation in order to prevent the disease, since 

 turnips can be grown in short rotation year after year on the same soil provided 

 the soil is kept sufficiently supplied with lime. 



" Little leaf " of deciduous fruits, R.. W. Hodgson (Mo. Bui. Cal. Com. Jlort., 

 7 (1918), No. 9, pp. 529-532, fif/s. 3). — In a progress report of studies on little 

 leaf, it is stated that in the exceptionally dry season of 1917 little leaf was 

 unusually prevalent, particularly in dry-farmed sections where the water sup- 

 ply is early exhausted. A decided relation of the occurrence of the trouble to 

 light sandy soils was also observed. Most regions of California have, of the 

 conditions related to winter dormancy elsewhere, only that of soil moisture 

 deficiency. Severity of desiccation may be expressed by the development of 

 little leaf, which is frequently present in only a portion of a tree, possibly a 

 part which is deficient as regards water supply and which is backward as 

 regards maturity. 



On the other hand, a different type of injury is associated with overirriga- 

 tion, apparently due to exhaustion of tlie food reserve due to the abnormal 

 continuation of growth late in the season. 



A tree may suffer from the lack of moisture, it is thought, even when the 

 water table has been raised by irrigation to within a foot of the surface, 

 since only the capillary water above the water table can be utilized. This may 

 account for the presence of little leaf where the water is near the surface. 

 The rise of the water may actually deprive the roots of their capillary water 

 supply under the conditions thought to exist in this region. 



A new disinfectant for pear blig'ht, F. C. Reimee (Mo. Bui. Cal. Cant. Hort., 

 7 (1918), No. 10, pp. 562-565). — In experiments which were started in June, 

 1918, to test the effectiveness of disinfectants for pear blight on wounded 

 trees, it was found that under specially favorable conditions as regards con- 

 centrations, etc., the application of Bordeaux paste, corrosive sublimate, cresol, 

 lime-sulphur, blackleaf 40, and chlorazene failed to prevent severe infection 

 by pear blight brushed on wounded surfaces. Cyanid of mercury v/as com- 

 pletely preventive at 1 : 500, while at 1 : 1,000 occasional development of pear 

 blight occurred and at 1 : 300 severe injury was cause<l. It is thought, there- 

 fore, that a strength of 1 : .500 is both safe and effective for application to tree 

 wounds. Corrosive sublimate is considered effective for use with the tools 

 employed for cutting out diseased wood, the only curative treatment yet found 

 to be effective against pear blight. 



Citrus canker [in the Transvaal], I. B. P. Evans (So. African Fruit Grower, 

 5 (1918), No. 3, pp. JfJ/, Jf9). — A resume is given with remarks made at the Trans- 

 vaal Agricultural Union Sleeting, September, 1918, on citrus canker in regard 

 to its appearan«e at different points in the Cape and Transvaal Provinces. 

 The disease is said to have spread to an extraordinary extent in the citrus 

 orchards on account of the exceptionally wet season of 1917. Vigorous action 

 resulted in complete suppression of the disease in several districts, so that 

 it is hoped that it may soon be completely eradicated in these regions. 



Bud curl of the lemon tree, C. C. Miller (Mo. Bui. Cal. Com. Hort., 7 (1918), 

 No. 9, pp. 515-519, figs. 5). — Explanation is given of the author's conception re- 

 garding the production of bud curl or pinch at the grafting union in case 

 of lemon trees (especially when grafted on orange stock), and of the means 

 to be employed to remove or rather to avoid such obstruction to the flow of 

 elaborated sap towai'd the roots, The plan discussed involves slitting the 



