CUISINE & CULTURE
ELLEN PEFFLEY
Autumn is prime time to choose landscape trees with a fall color display. The season’s warm fall soils favor root establishment.
Not all trees have foliage that change from their summer green to autumn color. The length of days is the main trigger for the change from green summer foliage to the fall colors. Days shorten in the fall, which trigger a cascade of events starting with the green pigment chlorophyll that ceases to be synthesized. The chlorophyll pigment has been masking other pigments. As chlorophyll degrades, the other pigments that confer autumn colors become visible: yellows, golds, oranges indicate the presence of carotenoids; reds and purples, anthocyanins. There are many more plant pigments that are in color pathways.
Pigment molecules remain high during autumn’s warm, sunny days and cool nights, intensifying foliage colors. The higher the level of pigments, the more vibrant the color.
A few uncommon trees with fall color are adapted to West Texas: Flameleaf Sumac (Rhus lanceolata). Small to medium size deciduous tree. Masses of tiny, white, clusters that attract butterflies and bees mature to red berries in the fall and winter. It is deciduous, narrow leaflets that change to spectacular flame red in the autumn. It is native to western Texas, cold hardy.
Rusty Blackhaw Viburnum ( Viburnum rufidulum). Small to medium shrubby deciduous tree with broad crown. Clusters of white flowers appear in late spring, maturing to dark purple fruit in the fall. Glossy foliage turn red, mauve, or orange in the autumn. Cold hardy. It is an attractive tree, with showy flowers, lacquered leaves, fall color and fruits. Its slow growth makes it look like a shrub for a number of years. Works well as an understory tree.
Mexican Buckeye ( Ungnadia speciosa). Small, shrubby, deciduous multi-trunk. Butterflies and bees are attracted to the fragrant, pink flowers that appear in 1-inch clusters in early spring. Flowers mature to small, hard, dark brown seeds with a white “eye.” Green leaflets turn yellow in the fall. An attractive understory tree but flowers best with half-day of full sun.
American smoketree ( Cotinus obovatus). Small deciduous tree with rounded crown, reaches 15 feet in height. In mid-spring rosy panicles cover the tree, appearing as drifts of “smoke.” Olive green summer foliage changes to fall color ranging from brilliant yellow to gold, apricot and orange.
Ellen Peffley Harp, a retired professor of horticulture at Texas Tech University, writes about gardening for several Texas newspapers.
