There are plenty of Bonsai tools out there which not everyone will need, but are of great help to those who are serious about Bonsai cultivation and want the best for their tree. Bonsai brushes are a great example of this. Sure, in real life, there's no one out there brushing the redwoods and pines of the world... but in a Bonsai setting, a tree can be greatly enhanced with the right brushing every now and then.
A good Bonsai brush or two is a very multi-purpose item, and it can be especially helpful for those seeking more complicated\difficult tree styles, such as ones incorporating deliberate deadwood.
Using A Brush To Improve The Look And Health Of Your Bonsai
There are two main uses for brushes that are applicable to almost any form of Bonsai cultivation:
1 - Exposing the roots
One element of traditional Bonsai display is to have exposed roots above the soil layer, which are ideally about as wide as the tree's canopy is on top. However, over the months and years, it's easy for soil to build up over the roots. So, a softer brush can be used to sweep dirt away from the upper roots, making them more prominent without damaging them in any way.
2 - Lightening the trunk and major branches
Over time, the trunk and branches of a Bonsai tree will accumulate layers of dirt and grime, just like any tree. For some, this is desirable, especially if they're shooting for a naturalistic feel. However, for a more pristine-looking Bonsai, a harder brush can be used to clean off the layer of dirt, which also makes the exposed surfaces look less dark.
This could also be used to enhance "windswept" styles. If you want the appearance of a Bonsai that's constantly experiencing winds from a certain direction, don't brush the windward side. Just brush the leeward surfaces, to realistically suggest they have far less dirt sticking to them.
Bonsai Brushes And Deadwood
Many advanced Bonsai styles deliberately incorporate deadwood, as exposed broken branches (jin), hollows from broken-off branches (uro), or deadwood attached to the trunk (shari). The issue here is that, of course, deadwood will partially rot. It creates a brittle, cork-like oxidized substance which can detract from the look of the tree, as well as preventing it from having treatments applied that preserve the wood.
In these cases, a strong metal brush can be used to clean out the oxidized materials. Power tools can be used, but it's not always a good idea since it becomes easy to start scratching up the wood you're looking to preserve. Brushing by hand with a stiff metal brush will allow you to remove the "cork" without unnecessary damage to the solid deadwood beneath.
Then utilize a product such as lime sulfur-based jin seal to coat the deadwood you wish to preserve. This is generally done with a nylon brush. Just be certain you wash the brush very thoroughly afterwards as lime sulfur is highly alkaline and corrosive to organic materials, like eyes and fingers. Always use protective gloves and goggles when working with lime sulfur.
A Bonsai beginner might not need brushes, but a set of brushes is still an excellent idea for advanced enthusiasts, and they make a great gift as well. And as always, play it safe and check out care guides for your specific breed before attempting any major training or deadwood work.