In my fourth post, I asked the question why there are no magnolias in Europe. Magnolias are found here in eastern North America and fossils tell us that they were once part of the forests of Europe, but now they are found only in North America; the European magnolias are extinct.
The answer lies in the effects of the Ice Age. During the last Ice Age, ice sheets several miles thick covered much of North America and Europe. The North American forest, including its species of magnolias, was able to retreat south, even into the mountains of Northern Mexico where it could find a refuge from the deep freeze. In Europe however, there was no suitable refuge to the south in which the European magnolias could survive the Ice Age. They were driven into the Mediterranean Sea and that was that! As the ice sheets receded, the North American magnolias were able to spread northward again and to be part of the recolonization of the post glacial landscape. This Ice Age history helps explains why the forests of eastern North America (including the forests of Delaware County!) are so much richer in species diversity than the forests of Europe.
Unlike the magnolia's flowers, this rhododendron's blooms will hardly be affected by a late snow.
