This earlier post described the four branch types peculiar to jujube trees: primary (extension) branches, secondary (non-extension) branches, fruiting mother branches, and fruiting branchlets. Also mentioned were the two bud types, main and secondary, and that each could have either strong or weak vigour. The type and strength of a particular bud determined the branch type that developed.
The focus in that post was on terminal main buds (those at the end of a branch), and how the strong ones produce permanent extension branches that form the structure of the tree, while the weak terminal buds produce fruiting mother branches.
This week picks up where we left off, with the primary branches, but this time we’ll cover the non-terminal buds. That is, the buds along a branch rather than at its end, and what these develop into. And from there we’ll go on to discuss how the other branches form.
Normally the main buds along a permanent branch remain dormant while that branch’s terminal main bud remains strong and produces extension growth. When that terminal bud weakens however, and produces a fruiting mother branch, some of the main buds further down the branch will break dormancy and produce new growth.
A strong main bud along a permanent branch will produce a new permanent branch that adds to the overall shape of the tree:
A weak main bud along a permanent branch may also break dormancy and produce a fruiting mother branch:
Remember how a fruiting mother branch — which looks more like a pine cone than a branch! — is a bunch of very compressed shoots containing several main and secondary buds? If a main bud in a fruiting mother branch then comes out of dormancy, a new permanent (structural) branch will again form:
A strong secondary bud along a permanent branch will produce a secondary branch. This branch type has a distinctive zigzag growth, caused by the alternating nodes changing the direction of growth:
Secondary branches do all their growing in their first year, as the terminal bud responsible for growth dies by the end of the first year. While a secondary branch will survive for many years, its end will deteriorate back to a node over time, where it dies:
During the first year’s growth of a secondary branch, its secondary buds at each node will produce fruiting branchlets, while its main buds remain dormant. These main buds then break dormancy in the second year to produce fruiting mother branches.
Here is a current season’s secondary branch showing fruiting branchlets from secondary buds. We know this branch to be less than a year old by its colour and texture — predominantly reddening but with hints of green still present, and with the shiny, smooth look of ‘green’ wood.
Below are fruiting branchlets from newly forming fruiting mother branches on a secondary branch in its second year of life. Again the colour and texture age the wood as between one and two years old, in that it is slowly developing a more brown-grey colour and has a more textured surface. Unlike the photo above, where the fruiting branchlets come from buds almost flush with the secondary branch, these branchlets come from slight extensions which are the growing fruiting mother branches. These mother branches will extend a little further and look more like pine cones with each passing year.
And here are fruiting branchlets from fruiting mother branches on an older secondary branch, which is noticeably more grey than the younger branches above. Mother branches only grow a millimetre or so each year.
As mentioned earlier, fruiting mother branches will develop from weak main buds on permanent branches. However, most branches of this type will come from the main buds on secondary branches. As the fruiting mother branches are the ones to produce fruiting branchlets, this means most fruit will come ultimately from secondary branches — branches which do not grow after the first season. Something to bear in mind when pruning, a topic we’ll cover in due course!
Also mentioned earlier was that a fruiting mother branch is a group of very compressed shoots comprised of main and secondary buds. The terminal bud extends the growth of the branch slightly each year, for about ten years after which it is no longer productive.
Fruiting mother branches can produce up to ten fruiting branchlets in a whorl:
The fruiting branchlets themselves come from weak secondary buds in the mother branch. (As well as from weak secondary buds on secondary branches as mentioned earlier.) Please read this if interested in further detail on the anatomy of a fruiting branchlet.
A peculiarity of jujube trees is that the fruiting branchlets are deciduous and have mostly fallen off the mother branches by the following winter. Some occasionally remain on the tree but they will never regrow:
and come away easily if knocked.
And that concludes the discussion on jujube tree branch development!
Going further, this post breaks down the structure of a fruiting branchlet in more detail, while this post describes the anatomy of a flower in more detail. And this post documents a flower’s life from bud to fully open and ready for passing pollinators.
All we need (I think!) to conclude the whole branch-flower-fruit thing is the documentation of a flower developing a fruit — and that is definitely coming!
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Comment from: Member
The great fascination I have with this post, Kristy, is how it illustrates so graphically the prolific potency of Jujube trees to bear fruit. Just look at the above photo of the Chico in flower. What other tree has fruiting branches that drop off when their job is done? Such dignity in letting the mother branch get on with her job each year to repeat the birth of multiple fruit branchlets for over ten years. Amazing stuff!
Comment from: Member
Hi Adrian, yes, they are pretty amazing trees with their unique way of doing things.
Most fruit trees set their flowers the previous season ready for the next spring, and a reason some types will only fruit on one-year-old wood minimum.
But jujubes, well they just get on and ‘git ‘er done’ in one hit!
I find it interesting that the fruiting branchlets resemble compound leaves at first glance, because they act like many fruit tree leaves too, in that they’re deciduous. Just as deciduous trees break down the chlorophyll in their leaves and reabsorb the molecules as an energy-saver - hence the colour changes as the removed green pigments reveal other pigment colours in the leaves - jujube branchlets also turn a yellow colour before dropping off.
And as a deciduous tree relies on its fallen leaves to further decompose and recycle nutrients back into the soil and re-feed it, these dropping branchlets probably have the same purpose.
So, I guess in terms of energy conservation and usage, jujubes took one path, while other fruit trees took another, for the same end result/net effect?