Sunday, December 16, 2012

Deciduous Conifers

The mention of “conifer” invokes a picture of evergreen trees like pines, firs and spruces. Those trees are conifers, their “fruits” are cones, and they do hold onto their “leaves” (that is, needles) all winter. There are other conifers, however, that don’t fit that profile. Junipers, for example, have fruits that appear to be blue berries but in fact are cones with fused scales. Other conifers have leaves that change color and fall off every winter. Those trees are known as deciduous conifers. Bald cypress (Taxodium distichum) is one of two that are native to Georgia.

Fall foliage of Taxodium distichum
Other native deciduous conifers in North America are the larches (Larix spp.) which grow more north of Georgia, the pond cypress (Taxodium ascendens) which is also native to Georgia, and several non-native trees such as the dawn redwood (Metasequoia glyptostroboides) and the Chinese swamp cypress (Glyptostrobus pensilis).

I recently came upon a group of bald cypress trees (Taxodium distichum) that were turning brown and shedding their needles. They also happened to have some fruit still attached so I stopped to gather some and take some pictures.
Taxodium distichum

As the cones ripen, the scales separate, revealing wrinkled brown seeds inside. 

As we reached up to pick some of the ripe cones, they shattered in our hands. We found one unripe cone; you can see the scales are still tight compared to the broken one.

For comparison's sake, I stopped by a church that I knew had a dawn redwood (Metasequoia glyptostroboides) planted there. I knew the two trees looked similar so I wanted to find the differences. The two differences that I noticed immediately: the cones and seeds were very different, and the foliage on the dawn redwood disintegrated in our hands.

Metasequoia glyptostroboides

Look at those tiny, papery seeds next to the cones! Once the seeds are released, the cones do retain their shape and would make nice decorations.

Dawn redwood upper; bald cypress lower

Here is a picture of the foliage of both trees side by side. You can see that the individual needles are falling off the frond of the dawn redwood (upper in the picture). The foliage of the bald cypress (lower) is also softer to the touch.

Ripe cones of bald cypress

Bald cypress is a wonderful tree for the landscape. It is very tolerant of wet areas and so is one to consider if you are dealing with poor drainage. And the next time someone tells you that conifers are evergreen, you can tell them "Not always!"

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