Chionanthus virginicus (White fringetree)
Chionanthus retusus (Chinese fringetree)
There are four fringe trees in the Park, and like many of the trees of the related species in the Park, they have a symmetrical placement about an axis, in this case the east-west axis. See Wikipedia entry here.
Chionanthus is a genus of about 80 species of flowering plants in the family Oleaceae (like olive trees). The flowers are produced in feathery panicles, with a corolla divided into four slender lobes: they are white, pale yellow, or tinged pink. The fruit is a drupe containing a single seed.
The white fringetree flowering in the northeast triangle in May, looking east. This one is a white, or American, fringetree.
Fringe tree factoids:
It is a deciduous tree bearing beard- or fringe-like clusters of flowers in late spring and berry-like fruit on stems in late summer. Each flower has four long, narrow, white petals.
It, like the katsuras and honey locusts in the Park, is usually dioecious, having separate male and female trees, only the latter bearing dark blue, olive-shaped fruit enjoyed by the wildlife. It is in the same family, Oleaceae, as the olive tree.
The genus name comes from the Greek chion meaning snow, and anthus meaning flower. An anthology is a collection (logia) of "flowers" of words.
Fringetree in the southeast triangle in May, just southeast of the white pine.
This seems to be a Chinese fringetree, with whiter, clustered flowers looking like cotton balls. The flowers are more upright instead of drooping. Chinese fringetrees flower after the leaves appear, while white fringetrees flower before the leaves appear.
The other two fringetrees to the east of this one are white fringetrees.
White fringetree flowers on the left; Chinese fringetree flowers on the right in May.
Botany 101 Bonus
It's sometimes a tough life being a tree. Deer will eat your bark. Insects will drill into your wood to lay their eggs. A tree can get sick from a virus, a bacteria, a fungus, or a worm. What's a tree to do?
Just as your skin is a barrier against tiny organisms that can harm you, a tree's bark is its first line of defense. This is why it's important not to injure the bark of a tree or break off a branch: these actions create openings for pathogens. A tree also has defenses like thorns, as on our 19th Street Washington hawthorns. Trees manufacture foul-tasting chemicals that discourage insect pests, like the tannins in the acorns of our red oak. Some trees even release a chemical into the air when damaged by an insect pest, and this chemical attracts other insects that prey on the insect that damaged the tree.
Trees like our fringetrees can be infected with a group of fungi called anthracnoses that infest the budding leaves. Although not usually killing the tree on first infection, recurrent infections can eventually kill the tree outright or make it weaker so it is attacked by other pathogens. The signs of a tree infected with anthracnose are dark patches on the leaves in some sections of the tree (anthracnose comes from the Greek word for "coal"). Treatment includes removal of dead and infected leaves, disposal of these leaves away from the tree, avoidance of over-watering especially in the spring, and possibly fungicides (chemicals that kill the fungus). It is also important to clean pruning instruments with a dilute bleach solution or alcohol between trees to avoid spreading an infection.
Anthracnose spots on a leaf.
Different species of trees have their own anthracnoses. Trees have some resistance against infection because they have evolved in the same environment with the fungus. Trees that don't have resistance genetically are killed off by the fungus. When a foreign anthracnose is introduced to a new ecosystem, trees can be devastated since they have developed no resistance without exposure over time. For example, the dogwood anathracnose was introduced to this region in the 1970's and has been killing many dogwoods. Likewise, the beech anthracnose has been a big problem for the beeches in the northeast United States. In 2020 in Baldwin Park two dogwoods and our only beech tree died, probably from anthacnoses.