|from the March 23, 2009 Newsletter, issued from near
BLACK CHERRY TREES FLOWERING
When I passed through here last June I photographed cherries on the Black Cherry tree, PRUNUS SEROTINA, next to my trailer. That picture appears in the next section. This week the same tree has been full of flowers, setting the stage for June, 2009 cherries. Below you can see flowers and leaves on the same branch as above.
Below you see a single flower in the panicle of flowers shown above. What an elegant little blossom it is, its five white petals affixed so geometrically around the rim of the cuplike hypanthium, male stamens also arising from the rim, alternately bending toward the flower's center or leaning away from it, and in the center of the hypanthium cup the pale, irregularly shaped thing is the stigma atop the female pistil. Below the stigma lies the green ovary, which later will mature into the cherry.
That cuplike hypanthium is worth fixing in your mind because it's so typical of many genera in the huge Rose Family to which Black Cherry trees belong. Recently we've seen hypanthia in plum flowers, also members of the Rose Family. Most flowers have stamens and petals attached at the base of the pistil, not from the hypanthium's rim, and with nothing like the hypanthium, which is like a little bowl holding a single cherry inside it.
from the June 16, 2008 Newsletter, issued from near
from the February 23, 2009 Newsletter, issued from near
Right now that same tree is leafless, but its buds are expanding, even bursting, as shown below:
In this week's picture the three buds at the twig tip are leaf buds. The bud scales' green patches show how the buds have enlarged, exposing tender new growth that earlier was protected by the smaller, dark chestnut scales. Before long leaf-bearing stems will emerge from these buds.
Below the three leaf buds a flower bud already has burst. The green, granular items at the far left are future flowers that will be held in an elongate, dangling cluster called a raceme. By the time the flowers are open leaves will have appeared. During warm, sunny days, you'd be surprised how fast the buds are enlarging, and how much farther from the flower- bud the future raceme of pretty white flowers emerges.
from the April 28, 2013 Newsletter issued from the Frio
Canyon Nature Education Center in northern Uvalde County, southwestern Texas, on the
southern border of the Edwards Plateau, USA
That's the Black Cherry, looking healthy and at home here despite our proximity to Mexico's vast Chihuahuan Desert just west of us, and despite the long-term drought we're experiencing now.
The raceme of white flowers in the picture is exactly like those on the big Black Cherry next to my old hermit trailer back in Mississippi. However, the leaves of our Dry Frio tree are a bit different. Their smallish blades are held on petioles much longer than I'm used to, plus the leaves' margins are more coarsely toothed, or serrated, than leaves on trees I'm familiar with back East. In the picture at the top of this page you can compare the leaves in the above picture with those on the tree next to my hermit trailer.
It turns out that here in southwestern Texas our Black Cherries belong to a different variety than the typical one back East. In fact, four varieties of Black Cherry, Prunus serotina, are recognized for North America, with others farther south. Black Cherries occur in much of the Mexican highlands as well as Guatemala. You can see a distribution map showing many tropical-American "islands" of Black Cherry populations, as well as an isolated population here on the Edwards Plateau, here.
Our variety of Black Cherry endemic to the Edwards Plateau region of southwestern Texas is called the Escarpment Cherry, PRUNUS SEROTINA var. EXIMA. It's distinguished physiologically from other Black Cherry varieties by almost or entirely hairless leaves with more coarsely toothed margins, longer petioles, and, growing up to 50 ft tall (15m), a potential height intermediate that of the taller Eastern Black Cherry (P. serotina var. serotina) and the shorter Southwestern varieties, virens and rufula.