How Do Palms Survive Hurricanes?

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The destructive force of typhoons and hurricanes are no joking matter. Human structures are torn to shreds and flooded in the blink of an eye. It is devastating to say the least. With all of this destruction, one must wonder how native flora and fauna have coped with such forces over millions of years. The true survivors of these sorts of storms are the palms. What would completely shred an oak seems to ruffle a palm tree. What is it about palms that allows them to survive these storms intact? 

To better understand palm adaptations, one must first consider their place on the evolutionary tree. Palms are monocots and they have more in common with grasses than they do trees like oaks or pines. Their wood evolved independently of other tree species. Take a look at a palm stump. Instead of rings, you will see a dense structure of tiny straws that resemble the cross section of a telephone wire. This is because palms do not produce secondary xylem tissues that give other trees their rings. This makes them far more bendy than their dicotyledonous neighbors. Whereas the woods of oaks and maples are really good at supporting a lot of branch weight, it is considerably more rigid than that of palms. Palms forgo heavy branches for large leaves and therefore invest more in flexibility. The main stems of some palm species can bend as much as 40 to 50 degrees before snapping, a perfect adaptation to dealing with regular storm surges. 

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Another adaptation of the palms are their leaves. Unlike most trees, palms don't bother with spindly branches. Instead, they produce a canopy of large leaves supported by a flexible midrib. These act sort of like large feathers, allowing their canopy to readily shed water and bend against even the strongest winds. Although their leaves will snap if buffeted hard enough, palm canopies accrue considerably less damage under such conditions. Another adaptation exhibited by palm leaves is their ability to fold up like a paper fan. This reduces their otherwise large surface area against powerful winds. 

Finally, palms have rather dense roots. They sacrifice size for quantity. Instead of a few large roots anchored into the soil, palms produce a multitude of smaller roots that spread out into the upper layers of the soil. This is especially useful when growing in sand. By increasing the number of roots they put down, palms are able to hold on to a larger volume of soil and therefore possess a much heavier base. This keeps them stranding upright in all but the worst conditions. 

Of course, these are rather broad generalizations. Not all palms have evolved in response to such punishing weather events. Research has shown that such adaptations are more prevalent in palms growing in places like the Caribbean than they are in palms growing in the rainforests of South America. Regardless, their phylogenetic history has stood the test of time and will continue to do so for quite some time. 

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Further Reading: [1] [2]