GRAPE DISEASES 263 
may be noted: certain fungi, insects, lack of phosphoric-acid 
and meteorological conditions. Those agencies which are 
thought to increase or favor shelling are: a weakening of the 
vines due to overbearing, heavy vegetative growth, excessive 
nitrogen supply emphasized by over-tillage, prolonged drought 
or excessive rains followed by drought, and a poorly developed 
root-system. One authority concludes that a lack of potash 
is in many cases the primary cause. There is considerable 
evidence, however, that this is not a factor. The agencies 
already listed as favoring the trouble may be regarded as 
exciting causes. 
Control. 
Since the main cause of shelling is apparently deficient 
nourishment, steps should be taken to correct such conditions. 
The soil should receive attention; potash should be applied 
where needed. Cultivation of poorly-nourished vines aggra- 
vates shelling; proper cultivation is essential. Care should be 
taken to properly handle vines that overbear; such plants 
need an adequate food-supply. In France it has been advised 
that shoots be pinched or cut off after the development of six 
to eight leaves where the grapes are borne; or twelve to fifteen 
on those shoots not carrying fruit. This diverts the elaborated 
food from the shoots to the berries. This procedure is said 
to give satisfactory results in France. 
REFERENCES 
Sturgis, W. C. Notes on the so-called ‘‘shelling’”’ of grapes. Con- 
necticut Agr. Exp. Sta. Rept. 1896: 278-281. 1897. 
Rainsford, E. H. Coulure, or non-setting of grapes. Queensland Agr. 
Jour. 10: 41-42. 1902. 
Clinton, G. P. Report of the botanist for 1906. I. Notes on fungous 
diseases, etc., for 1906. Grape, Vitis sps. Shelling and rot. Con- 
necticut Agr. Exp. Sta. Rept. 1906 : 315-316. 1907. 
Lodeman, E.G. Some grape troubles of western New York. Shelling 
or rattling. Cornell Univ. Agr. Exp. Sta. Bul. 76: 413-440. 
1894. 
