|MadSci Network: Botany|
It will vary from over 95% of the fresh weight in plants such as lettuce and wax begonias to less than two percent for some seeds. Drying seeds to a low moisture content greatly extends their life in cold storage. In general, you would expect woody plants would have lower moisture contents than nonwoody ones. Succulent plants, such as cactus, usually have high water water contents. Cactus often contain 90 to 94% water when fully hydrated. Edible pads of prickly pear cactus average 85% water. Many aquatic plants, such as elodea, have water contents (over 95%) because they do not need much supporting tissue such as xylem. The table in the references gives water contents of common fruits and vegetables, such as banana (74%), white potato (79%), grapes (81%), pineapple (87%), celery (95%) and radish (95%). The equilibrium water content of lumber varies greatly depending on the relative humidity of the air. References Table of Water Content of Fruits and Vegetables Re: how much water is in a watermelon?
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