Tree of the month for September: Tulip tree of the Nile
By David Gress
The Nile Tulip tree explodes with a dazzling display of yellow flowers from July to September. Despite its attractive flowers and foliage, its many merits must be relatively unrecognized by most people in Santa Barbara, as it is currently underused in our landscapes.
It was first used in Santa Barbara in the late 1940s as a street tree. It is only recently that it has been rediscovered to be a decorative, hardy tree – a tree we should certainly be planting more frequently along our streets and in our parks and gardens.
Its most remarkable feature is its flowers. Each is large (up to 3 inches long) and has five bright yellow petals. These petals are fused into a funnel shape, are slightly ruffled along the edges, and are streaked with red or brown stripes in the throat. The flowers occur in panicles (clusters) at or near the ends of the branches. These clusters stand out brilliantly against the dark green leaves.
A good point is that a Nile tulip tree starts bearing flowers when it is only 4 to 5 years old – you don’t have to wait long for its pretty flower decoration!
The flowers are pollinated primarily by bees, but their sweet nectar is also very attractive to butterflies and ants.
After the flowers are pollinated, the fruits that form are bean-like pods 1 foot long, which turn brown when ripe and open lengthwise. Inside each pod are hundreds of seeds surrounded by papery wings. Winged seeds are quickly dispersed by the wind. After the seeds leave, the dried pods become twisted spirals that can cling to the tree until the next flowering season.
This evergreen tree has a lush tropical appearance – so it’s a good surprise that it is drought tolerant once established – a definite advantage in our Mediterranean climate.
It is a small to medium sized tree. When fully grown, it grows 30 to 40 feet in height with a spread of 20 to 25 feet. It can grow fast or slow (between 3 and 6 feet per year), depending on the amount of irrigation it receives. When young, his growth can be somewhat irregular and lanky; it may require gentle pruning to train the development of its crown.
Its pinnate compound leaves can be over a foot long. They have up to seven glossy, dark green, oval leaflets, arranged parallel to each other along a central stem. The size of the leaflets ranges from 3 to 7 inches in length and 1½ to 3 inches in width, with the largest leaflet at the terminal end of the leaf.
The bark is a light gray that with age will turn darker gray, become finely cracked, and peel off in patches to reveal a light brown bark below.
As indicated by its common name “Tulip tree of the Nile”, it is native to equatorial East Africa. There it is found growing in savannas and on dry rocky ridges and hillsides.
In its areas of origin, the Nile Tulip tree has been widely used for its beautiful wood, which is beautiful, brownish-yellow and fine-grained. As a wood, it is easy to cut, while being exceptionally durable and resistant to termites. It is easily carved for making utensils and crafts. With all these qualities, it is appreciated for cabinetmaking and fine carpentry. It is also harvested and used for more basic utility purposes as fuel and charcoal.
In traditional African medicine, its leaves, bark, and roots are used to treat a wide variety of ailments, including aches and pains, arthritis, and respiratory problems. Interestingly, its leaves are a favorite and nutritious food for elephants.
Because it is a fast-growing, drought-tolerant tree, the Nile Tulip tree has been widely used in Africa and other parts of the world as a windbreak, for erosion control. of soils, to improve soil nutrition, for soil moisture retention, and for reforestation.
The botanical name of the Nile tulip tree is Markhamia lutea. We gave him the name of the genus, Markhamia, by Berthoud Seeman in honor of his friend Sir Clements Robert Markham (1830-1916), British geographer, explorer and author. Markham is well known for collecting quinquinas in Peru and then bringing them to India, providing a local source of quinine vital for treating deadly malaria. The specific epithet, lutea, comes from the Latin word “luteus”, which means “yellow” and refers to the bright yellow flowers.
The Nile tulip tree belongs to the large plant family, Bignoniaceae, which includes trees and shrubs that we all know in Santa Barbara, like the Jacaranda (Jacaranda mimosifolia), the trumpet vine (Distictis sp.), Cape honeysuckle (Tecomaria capensis), and the African tulip tree (Spathodea campanulata). (The African tulip tree has spectacular orange flowers that appear during the same flowering period as its cousin, the Nile tulip tree.)
It is best to propagate it with fresh seeds, although the seeds can be stored for a short time at room temperature. They normally have a germination rate of around 50%. The seeds germinate quickly when sown in a sunny location, are barely covered with soil, and are kept moist.
It is sensitive to cold but can survive temperatures up to 25 degrees without damage. Colder temperatures will cause its leaves to drop and may cause limb dieback. It is remarkably drought tolerant once established, but, of course, will look great with occasional deep watering during the dry season. It can tolerate a wide range of soil types, but does best in deep, well-drained soil. It will grow best in full sun to partial shade.
While excellent as a street tree, the Nile Tulip tree is just the right size for residential yards and can easily be pruned to fit comfortably in small gardens and yards. If you are looking for a beautiful (but sturdy) tree to create a lush tropical atmosphere, you would do well to select – and enjoy – this almost forgotten tree.
Mature specimens of the Nile tulip tree can be seen in De La Guerra Square (between the Town Hall and the News-Press building), in the 300 block of West Pedrigosa Street (1 tree), in the Memorial Gardens of the Alice Keck park (2 trees), on the north side of Micheltorena Street in San Pascual (2 trees) and in front of the Presbyterian Church El Montecito (2 trees). Several saplings stand in the 700 block of State Street and in the 100 block of East Ortega Street.
Tree of the Month articles are sponsored by Santa Barbara Beautiful, whose many missions include raising public awareness and appreciation for Santa Barbara’s many remarkable trees and, in a long-standing partnership with the City Parks & Recreation Department, fundraising and tree planting along City streets.
Those who wish to honor a special someone can do so with a nice commemorative marker that will be installed at the base of an existing street tree in the city of Santa Barbara. Because Santa Barbara Beautiful has been involved in planting over 13,000 street trees to date, there are plenty of trees to choose from! Application forms are available on the Santa Barbara Beautiful website, www.sbbeautiful.org.
Article and photos by David Gress