Reaction wood has a different cellular characteristic to normal wood and is formed when branches or stems have been disturbed and the tree attempts to return to its original position.

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"When we looked at them in detail and brought them to the lab, I could see some of the stems actually had new growth of green lateral branches, and that said to me that these guys are regenerating in the field, and that blew my mind, " she told BBC News.

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The branches split off at directly opposing points and the stems bear between nine and 13 leaves in symmetrical pairs with a lone one at the tip.

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