A beacon for sailors

In an earlier publication, photos have already been shown of a tree species that belongs to the Casuarina family. In this case, a photo was taken of the cross-section of a needle with a DAPI long-pass fluorescence filter, which gives a nice image.

Casuarina equisetifolia is a tree that occurs in open, coastal habitats including sand beaches, rocky coasts and sand dunes. Trees can grow to over 30 m in height. It is native to South Sea islands such as Australia. The reddish-brown to grey bark is brittle and peels. Branchlets resemble pine needles and are very thin, 10-20 cm long and grey-green. 

Male and female flowers are present on the same plant and are inconspicuous. Male flowers occur in terminal spikes, while the female flowers are in small, axillary clusters. Fruits are tiny, winged nutlets that each contain one seed. The fruits are contained in woody, cone-like structures that are 2 cm long. Being a beach tree, the seeds are spread through the water. It is a salt-resistant and fast-growing ornamental tree that is suitable for wind protection and as a sand fixer.

Because of its striking shape and its location on beaches, the tree formed a natural beacon for shipping and you will therefore often find them indicated on sea charts. It was described in 1776.

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