Baobab trees store water in their swollen trunks, helping them endure long dry seasons in Africa.

The longer version

A swollen trunk gives these trees an enormous internal reservoir. The wood is soft and spongy, able to hold water taken up during the wet season, and the tree draws on it slowly through months without rain.

The shape also keeps the tree cooler, since a massive trunk changes temperature more slowly than a thin one. Thick bark reflects sunlight and resists fire. Leaves are shed during the driest part of the year, cutting water loss further, and the bare crown reduces the surface exposed to dry air. The enormous girth that results makes these trees easy to spot across a flat and dry plain.

Where this entry sits

Plants and Trees gathers ordinary and surprising details about how green things live, from the tallest forest giants down to the moss on a garden wall. Expect notes on flowers, seeds, roots, leaves, fungi, and the quiet tricks plants use to spread and survive. The full list sits on the Plants and Trees page, where every entry is listed in order.

← Entry 39 Entry 41 →

More From Plants and Trees

Eight more entries

Tree roots usually spread far wider than the crown above them, often reaching well beyond the canopy.

Photosynthesis turns sunlight, water, and carbon dioxide into sugar, releasing oxygen as a by-product.

Transpiration pulls water up through a plant as it evaporates from tiny pores in the leaves.

Bulbs such as onions and daffodils store food underground so the plant can regrow each spring.

Climbing beans curl around supports because one side of their stem grows faster than the other.

Pine cones open and close with humidity, releasing seeds when the air is dry enough to carry them.

Clover often folds its leaves at night and raises them again once morning light returns.

Seeds can lie dormant in soil for years and still sprout once light and moisture improve.

Read

Try Another Subject

Three collections