Print

Dalbergia

by Tony Bent

Dalbergia, a large genus of trees, shrubs and climbers (over 100) from the tropics and subtropics, is named after the Swedish botanist Nicholas Dalberg (1736- 1820).

After much searching, the only information I was able to find on Dalbergias was in a book called "The Complete Guide to Trees of Natal, Zululand & Transkei" written by Elsa Pooley, who I might add praises its worth as a good bonsai subject!

The species that bonsaists grow is Dalbergia armata, which is indigenous to southern Africa. It is a robust, spiny climber (10 - 30m), widespread in forest and riverine vegetations in Transkei and Natal, also from the Eastern Cape to Swaziland, Mozambique and Eastern Transvaal.

It is also named the Hluhluwe creeper, Thorny rope, and Doringtou or Monkey rope. The Hluhluwe part tells you where it comes from with the latter names being most appropriate as it looks exactly like that - a rope that grows in subtropical forests hooking on to adjacent trees with its thorns or spines in order to reach the sun.

The trunk can reach 150mm in diameter with the woody spines being up to 100mm long, entwining stems. The bark is dark, almost a charcoal colour. The leaves are fine, compound (up to 80mm long) with the leaflets in 10-20 pairs plus a terminal one (6-11 x 3-8mm), a dark bluey-green above and paler beneath. The leaflets close in overcast weather. The Dalbergia is deciduous, but new growth appears rapidly. The flowers are small, creamy-white and sweetly scented growing in dense terminal or axillary clusters (up to 100mm long) and are crowded towards the ends of branchlets. Flowering in October/November. The fruit are lemony-yellow to pale brown, flat (50 x 20mm) pods in conspicuous clusters (March-May). The leaves are browsed by bushbuck and the bark and leaves are a favorite of rhino!

When grown in a non-forest environment - in other words with nothing to hook on to - it grows into a large shrub/tree about 3m tall. Jessie Edwards showed me one at the side of the road on the way to Durban Airport.

The thorns or spines, if left, can turn into branches - although they are poker-straight and rather uninteresting in shape. I prefer to cut them off when they are young and still green and invariably a new branch is generated under the little scar. Lionel Theron, in his book, recommends that main design pruning is done in August and that light pruning is continued during the vigorous growth period to prevent the growth of large unattractive thorns.

Dalbergia, being essentially a climber, does not readily achieve good tapered trunks. I don't always accept this argument, as my oldest tree has a trunk that is beginning to thicken quite nicely - but remember that pruning is essential during the growing season so that branches do not thicken at the top of the tree. An excellent example of good taper is Gail's magnificent specimen!

I like to wire trees when they are very young, as they are most flexible and obliging. Wiring gets the tree away from a straight line - remember it is a climber. Also, it is more difficult to wire when the tree is mature as it is extremely brittle. Most important of all is that in wiring trees when they are young, you can dictate the style and eliminate the unnecessary scar tissue that occurs from having to cut off branches. I find trunks retain scar tissue indefinitely and do not callus easily.

Dalbergia are suitable for many styles such as Informal Upright, Leaning Trunk, Cascade, Semi-cascade, Literati and I've seen splendid examples of Root-on-rock and Root-over-rock at Bishopsford. In fact, most styles other than Formal Upright can be used.

Cuttings root relatively easy - I've done several cuttings that have been successful and I know that Gail builds up her stock that way. Dalbergia are not easy to get hold of, even in Natal, as commercial nurseries do not sell them. In the Cape, Bishopsford is the only nursery I know that sells stock.

To me, the very special joy of Dalbergia is that it is like having two entirely different trees! When the tree is in dormancy, the ramification of the branches is quite beautiful - this is one of the best points of Dalbergia, the ramification. You have a totally different tree when it is in leaf because of the dramatic size change and the incredible plateaus that are created by the leaves.

Species Gallery

Related Articles

Contact Us

We would be happy to hear from you should you like to find out more about the club, meetings or bonsai in general.

Send us a mail

Year Programme

We have an exciting calendar of club meetings, events and public exhibitions planned for 2017/8.

Learn more

Haiku

Last leaf has fallen

Tree will sleep and I will dream

Spring is tomorrow

Random Bonsai Tip

When you have too thin trunks, you could twist two or three saplings together, fasten them together with wire and allow them time to fuse; or graft two trunks together.