Here’s the word of the day: senescence. Here’s the tree of the day: Brazilian raintree. 
When we think of senescence we usually think of deciduous trees. Not huge, tropical canopied, thorny and dangerous Brazilian raintrees. 
Senescence happens to all trees. Even junipers and pines. Those third year needles that you clean off a pine? If you left them they’d turn brown and fall off. That old browning scale foliage on a juniper? Same thing.
What a trunk huh? 
And those thorns I was talking about. 
I have to stick my hand in there.
Here’s another BRT you should be familiar with. 
It’s got some yellow leaves too. And no matter how much water I give it it seems to be droopy all the time. 
Sad looking. 
But it’s not sick. See that new bud? 
Some trees, both tropical and broadleaf evergreen, have a hard time shedding old foliage and you have to help them out and defoliate them. 
Naked.
Some wire and I’m all set for the holidays.
Oh, wait?! Did I mention that it’s December? But….aren’t we NOT supposed to be working on tropicals at this time? Sorry, you’ve never heard that from me, my friends. Especially on BRT’s.
Here’s a third tree to throw into the mix. 
I like it. It makes me smile.
Let’s discuss the tropical legume we call the Brazilian Raintree (chloroluceun tortum). In Brazil it’s called tataré, and it’s native to the coast of Rio de Janero, in an area called restinga, a wet coastal stretch that goes from tropical to subtropical areas on the eastern shore of Brazil. It’s home to a broadleaf forest that has sandy soil that is both acidic and nutrient poor. A good place for a legume, which has the ability, working in symbiosis with a nitrogen fixing bacteria to, amazingly, pull nitrogen out of thin air and fertilize itself. The BRT is also a type of tree called a monsoon or drought deciduous tree. The restinga is a biome (an environmental designation) called a tropical/subtropical dry forest, bane forest or just monsoon forest. It is a place that gets a lot of water but also has a dry season, where the trees have adapted by dropping their leaves, just like deciduous trees in the northern climes do in the winter.
This is senescence in BRT’s. 
Droopy, off color, wimpy looking. Like some bonsai artists I know. 
Senescence is an adaptation by plants, in response to drought or low light levels, that, using the hormone abscisic acid, puts a tree into dormancy. It is the act of abscission, dropping leaves, that gave the name to abscisic acid.
But enough of that, how does all this relate to doing bonsai on a BRT? 
It means that we must be the stewards, the midwives, the facilitators, of the tree. 
Time to defoliate again. Before. 
Like they say, you can prick your finger but you can’t finger your pri…..
Ouch, right in the cuticle.
After. 
Here’s a quick pruning lesson. The red and blue arrows are pointing to nodes. The node is from whence the new leave or branch emerges. The space between the nodes is called an internode. 
This is true of all trees. Learn the words and you’ll be thought smart, like me. Or just be called a smart-ass.
On the BRT this is important because of a process called dieback.
Again, the circle is encompassing the node and the internode. 
Dieback can be significant on a BRT, it’s the process during which the tree compartmentalizes a wound so that it can heal. To be precise, if I cut here at the red line…..
the branch will die back to that main branch. Which is fine because I would want to remove the branch to there anyway. The problem is that it is taught to prune flush with the branch on most trees. If you do that on a BRT, the dieback will go like so:
and you’ll lose that whole branch to the next node. Therefore, you will see that I leave nubs on all my pruning points; it’s not lax scissor discipline but an understanding of the horticulture of the BRT. Does this mean that we can’t prune flush? No. Once the branch dies back, you can then do a flush cut.
Let’s get some wire on it. 
You’ll notice that the pad isn’t flat like this:
but rather on an angle so you can see the back branch. 
This helps to show depth in your trees. Now for the finish. 
I’ve broken a few rules I usually insist upon but I will always listen to what the tree is telling me.
You’re wondering about the very first tree, aren’t you? 
We haven’t seen it for a while have we? Don’t worry, there will be a YouTube video on it but, to hold you over, here’s the after pic. 
Lots of work.
Stay tuned for the video, I think it’s gonna be a cool one.
So, what did we learn today? We learned about senescence, about nodes and internodes and dieback. We learned about fingers and pricks. And that’s all I have to say about that.
Adam's Art and Bonsai Blog 
Love the transformation in that tree. It was WILD and now it’s tame and has a bright future! Thanks again for an informative video.
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Adam, would it be good practice to defoliate other legumes this time of year? I have a tamarind, a lysiloma bahamensis, and a couple poincianas.
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On the tamarind I would say no, they are very temperature sensitive and won’t grow back until its warm. If the leaves fall off don’t worry though. The poinciana should be deciduous and not have leaves through the winter. Even in Puerto Rico they are leafless throughout the winter.
I believe the lysiloma should be ok to do this too though. I don’t have one so I can’t tell you for sure though.
But you should only be defoliating if the tree is telling you it needs it.
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Ok thank you!
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Adam, hi. Love your blog! Would you be willing to sell some brazilian raintree seeds?
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If I had some I would but none of my trees flower. I know that Erik Wigert has a tree in the ground that flowers and sets seed, try contacting him. Wigertsbonsai.com
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Glad to know my intuition about defoliating my BRT in December was correct…
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Hi Phil! So defoliation of a Brazilian Rain tree is ok this time of year? I’ve removed some of the thorns, now the branches are bare in those spots on the branch. Should I prune back and start the process of creating tapered branches with foliage again?
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I prefer to defoliate during the growing season in spring and summer but sometimes BRT look like they need a haircut with yellowing leaves, droopy and all. That’s when I bring out the scissors…
Creating taper is a time consuming process like over years of cutting back, growing new twigs, cutting back to create taper, growing twigs and on and on. The process never ends so long as the plant is alive.
You can remove thorns anytime but as Adam mentioned don’t cut off the new bud which is near the thorn.
Yes, you can prune back to create taper. Read this post again and follow Adams advice…he’s very good ya know!
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Thanks Phil I will re-read it!
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I’m just starting out in tropicals and have been looking at the BRT. This was a great article for me.
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Very nice trees………..as usual
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Reblogged this on Wolf's Birding and Bonsai Blog.
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fantastic looking tree. do you recommend growing from seed?
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If you can find seed you can. They airlayer very easily though. Cuttings aren’t so easy. It the thicker the cutting the easier it is
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I just acquired my first BRT from Erik’s nursery after seeing some of your posts. I noticed you doing all this work in December, are there any general guidelines on when to do work on this type of tree? Should I be waiting until spring to repot this into some proper bonsai soil (I’m in Palm Beach area)?
Thanks,
Tyler
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It’s probably best for you to wait until spring for an initial potting into bonsai soil. The tree I’m working on is already in the proper soil and I’m really only doing very little to, even though it looks like a lot.
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I just acquired my first BRT from Erik’s nursery after seeing some of your posts. I noticed you doing all this work in December, are there any general guidelines on when to do work on this type of tree? Should I be waiting until spring to repot this into some proper bonsai soil (I’m in Palm Beach area)?
Thanks,
Tyler
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Tyler, Martha Goff has a book called Tropical Green Sheets that is my “Bonsai Bible” so to speak. Look on Ebay for one of them. I have both but the first book is the best and has the most of everything that is common bonsai in Fl. The second one has more of the unusual and more hard to find kinds of trees.
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Should the thorns be removed from the BRT? Will it hurt the tree? I’ve removed thorns, now the branches are bare and leggy up to where I stopped. Leaves are at the end of the branch. Will the tree back bud and grow to fill in the bare spots? Or should I prune the branches back and start over?
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You have to prune the tips to get Back budding or else the branch just continues to elongate and only has growth on the tips. Removing thorns does not hurt it, as long as you’re not cutting it flush and removing the bud at the same time
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Thanks for the info. I will prune back to the last bud and watch for new back budding.
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Should the thorns be removed from the BRT? My tree has leggyness, no foliage where the thorns were removed. Should I prune back and start over to get fuller branches with leaves?
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