Friday, December 26, 2014

Davidia involucrata. The Dove Tree.

The dove tree, also known as handkerchief tree, is an exquisitely beautiful and exotic tree from China and is the only species in its genus and forms a rounded tree that eventually grows 10–12 metres tall. In spring pairs of long drooping, white petal-like, heavily veined bracts frame a ball-shaped cluster of stamen either red and white or black and white appear an adorn all along the branches. The bracts are held well above the leaves, making the tree look as though it were covered with white doves. When a light breeze blows the bracts sway like dove wings bring the tree to life. 

The large mulberry shaped roundish, pointed, toothed, rich green leaves white felted underneath with about 8 distinct, raised prominent veins, up to 12 centimetres long and are very attractive in their own right and cover the tree nicely. When crushed they give off a fragrant spicy scent. In NZ the form that appears to be grown is D. involucrata var. vilmoriniana which differs in that the white felt underneath the leaves is absence.  There is another species recorded, D. laeta, but this is not recorded in NZ and is subject to botanical debate as to whether or not it is a separate species.

If you plant this beautiful and exotic tree as an ornamental, keep in mind that the tree will not flower until it is nearly five years old and that some trees blossom irregularly. Planted as a shade tree, the showy bracts will be a bonus whenever they appear. They are easy to grow but may sulk a little in the first few years and are best with other deciduous trees.

Once established, most trees need little if any fertilizer provided they are growing in good garden soil. If soil is poor, or if trees are recovering from pest or disease problems, fertilizing established trees in early spring can be beneficial.

Grow dove tree in light shade in deep, rich soil enriched with peat moss or leaf mold although it will tolerate full sun if the soil is kept evenly moist. It needs shelter from wind.

The Dove tree is an excellent tree for the small to medium sized garden. Trained on a single trunk it makes a wonderful specimen and when in full flower can be almost ghostlike.

Named in honour of father Pere Armand David (1826-1900), a French missionary to China who worked there independently as China was forbidden to foreigners. He collected many new plants in the middle of the nineteenth century.  When restrictions were lifted in the 1870’s David led two scientific expeditions for the French Government. Owing to various mishaps like his boat sinking, it was many years before his collections became known.

At that time Augustine Henry, a Chinese Customs Official collected specimens in his spare time and his leave for the Royal Botanic Gardens Kew. E recorded only one solitary specimen of Davidia while exploring in the high limestone mountains of Hupeh when on leave. The tree was in flower and made a great impression on him and he secured a specimen. He was unable to go back there later as he was transferred to another province. Henry saw the potential of a great variety of plant material and urged botanists at home in England to send out a fully professional collector. In one letter he says it would be worth it for the Davidia alone.

Finally Veitch’s nursery sent E. H. Wilson (1876-1930), later known as “China” Wilson to China to collect specimens for their nursery and introduction to England. He made the long and dangerous journey from England to meet Henry and then another long journey to Hupeh. With the help of the Chinese henry had employed he found the very place and the very tree, but the tree had been cut down and was used as a door post for a house. Later one night he camped in a grove of unfamiliar trees and examined them the next morning discovering that they were Davidia’s. In 1901 he sent home a large quantity of seed to Veitch’s.
However he was not the first to send back seed. Another French missionary, Father Farges, had sent a small packet of 37 seeds to the famous French nursery DeVilmorin. Only one germinated and it grew and finally flowered in 1906. A tree from Wilson’s seed flowered in 1911.

Interestingly the leaves of the Davidia in France differed from the one in England by being smooth on the underside of the leaves. They were named as separate species D.vilmoriniana (after DeVilmorin’s Nursery) and D. involucrata. Today with modern exploration and mapping Davidia is known to occur naturally in central and southwest China from Hubei to Ganzu and south to Guzhou, Sichuan and Yunnan provinces.

Davidia is a genus of one species, Davidia involucrata, a native of western China. In the wild it grows into a lovely tall symmetrical tree up to 25 metres tall with branches that tend to grow upward into a very shapely head. However in cultivation few grow more than more than 10 metres tall. 

Propagation of new trees is by sowing the large oval seeds usually stratified for 12 months in sand and leaving them outside for the weather to break down the chemicals and seed coating so the seed will germinate. Other ways to propagate is by layering or growing from cuttings in a propagating environment. Plants raised from layers or cuttings will flower before seedling grown plants as the parts of the plants used have past their juvenile stage. It may be worth experimenting with grafting particularly taking material from the trees with the largest bracts.
Young plants are easily transplanted into the garden. Plant with good soil and a compost mulch to give it a good start.

As this is a very nicely shaped tree and a fantastic spring flowering tree take care to train it as a specimen tree on a single trunk. It is great in a partially shaded position where the white bracts really show off their colour.

It is easy to grow and it has been said it is slow to start but I have not experienced this. It prefers a strongly seasonal climate and growing with other deciduous which simulates its native habitat. It is also spring tender meaning late frost will damage new growth and in extreme cases cause the tree to suffer badly. In Canterbury a warm north westerly wind will damage the newly emerged bracts which make the outstanding display.


Gardeners Chronicle May 10 1967 “Davidia’s the handkerchief tree” Sheila Pim pp11

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