What happens to the buds in spring?

The kidney is a rudimentary shoot. In plants of temperate climates, this is an adaptation to endure winter. Dense kidney scales, glued together with a resinous substance, reliably protect the delicate tissues of the future shoot from cold and moisture loss.

In the spring, with the beginning of sap flow, the buds swell, the scales burst and the tip of the young shoot appears. At its top, there is a growth cone, which consists of educational tissue. Thanks to organic matter coming from the root, cells divide rapidly and the shoot grows.