In this article:

This article details investigations of the roots of the sultana vine in which it was found:
(1) the rooting habit of the sultana vine is shallow and widespread, with considerable overlap of the root system of adjacent vines,
(2) sub-soiling prior to planting increases the depth at which the main roots normally develop, however the depth of penetration of the smaller roots is controlled by drainage,
(3) root pruning occasionally by winter plowing to a depth of 9-10 inches is benefical,
(4) the feeding roots are annual structures,
(5) the root growth commences about five weeks after the rise of the sap begins and three weeks after bud burst, and
(6) the great mass of feeding roots present by the end of November are borne on new extension growth.

The Root System of the Sultana

1932, The Journal of the Council for Scientific and Industrial Research, vol 5, pages 88 – 93

csiro 1932-4

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