Sap from a grape vine (Vitis vinifera). Sap within woody plants is carried upwards in xylem elements of the central stem. Grape vines have a high root pressure so that if stems are cut in early spring before leaves develop,the sap bleeds profusely,as here | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Burgess, Dr. Jeremy |
Taille de l’image : | 3421 px × 5125 px |
Model Release : | Non requis |
Restrictions : | - |