Since my poor umbrella bonsai has been declared dead, I decided that I might as well take a look to see what might have gone wrong. I was told that my plant's demise was probably due to root rot, and that if this were the case, the roots would be dark and mushy. However, when I took a look the roots were a light beige colour and quite firm. From the images I have seen of root rot, it doesn't appear the same, however that may just be my inexperience talking. The pictures show what the plant's roots look like, as well as the soil it was in. I am just curious, and I hope that I can learn from this so that I can try to prevent the same thing from happening in the future.
[img]https://i940.photobucket.com/albums/ad245/Sunshine-Cove/Bonsai6.jpg[/img]
[img]https://i940.photobucket.com/albums/ad245/Sunshine-Cove/Bonsai7.jpg[/img]
[img]https://i940.photobucket.com/albums/ad245/Sunshine-Cove/Bonsai8.jpg[/img]
. When I went to go check on my bonsai again, it seems that my mother had decided it was finished and threw it out. Currently, it is sitting in a grave of chicken fat and other compostables.
It was worth a try!
Sorry to hear that your tree went to the great compost bin in the sky ... so for nickle knowledge for the future, here is my 2 cents worth.
The pictures you show have roots with out root rot...however what IS missing are lots of fine feeder roots that should be present. The roots in the picture are anchor roots..they do nothing to provide nutrients to the plant.
So perhaps they died of to root rot...though I doubt it based on what you soil looks like. It would appear that your soil is made up of peat...which WILL dry out quickly and be a pain to rehydrate correctly...the dryness of the peat could and probably did kill off the feeder roots...in turn taking down the tree.
Outside of that explanation and based on your images...its the only explanation I can come up with...cause that tree looked healthy.
The pictures you show have roots with out root rot...however what IS missing are lots of fine feeder roots that should be present. The roots in the picture are anchor roots..they do nothing to provide nutrients to the plant.
So perhaps they died of to root rot...though I doubt it based on what you soil looks like. It would appear that your soil is made up of peat...which WILL dry out quickly and be a pain to rehydrate correctly...the dryness of the peat could and probably did kill off the feeder roots...in turn taking down the tree.
Outside of that explanation and based on your images...its the only explanation I can come up with...cause that tree looked healthy.
The weak root-mass definitely indicates a problem; most likely with the soil.
My first Schefflera arboricola plants came from a local garden center with a soil very similar in appearance to what yours is planted in. The more I learned about proper bonsai soil mixes, the more I began to realize that something wasn't quite right with what my plants were potted in. Once I got a suitable mix of my own and proceeded to repot the plants, I discovered that their root masses were very weak (as yours appears to be). The soil in and around the middle of the root ball was actually sopping wet---yet the rest of the soil around the outside of the pot seemed to be 'just right' (in terms of moisture) when I stuck my finger into it through the soil's surface.
In a nutshell, the soil at the center of the rootball was sopping wet and AT THE SAME TIME the rest of the soil remained relatively dry. I had to conclude that this was the explanation for the weak root mass.
Since switching to a much coarser peat-free mix, my plants have been thriving with healthy, robust root systems.
BV
My first Schefflera arboricola plants came from a local garden center with a soil very similar in appearance to what yours is planted in. The more I learned about proper bonsai soil mixes, the more I began to realize that something wasn't quite right with what my plants were potted in. Once I got a suitable mix of my own and proceeded to repot the plants, I discovered that their root masses were very weak (as yours appears to be). The soil in and around the middle of the root ball was actually sopping wet---yet the rest of the soil around the outside of the pot seemed to be 'just right' (in terms of moisture) when I stuck my finger into it through the soil's surface.
In a nutshell, the soil at the center of the rootball was sopping wet and AT THE SAME TIME the rest of the soil remained relatively dry. I had to conclude that this was the explanation for the weak root mass.
Since switching to a much coarser peat-free mix, my plants have been thriving with healthy, robust root systems.
BV
Thanks for the insight! I am completely new to gardening, so I wasn't sure how the roots were supposed to look. I suppose that with a little extra poking around and some more research, I'll try anew.
Thank you again for taking the time to help out a gardening newbie such as myself =) It really is appreciated!
Thank you again for taking the time to help out a gardening newbie such as myself =) It really is appreciated!
I admire your concern for the plants and desire to learn more! 
The following photos were taken from a healthy Schefflera arboricola (a.k.a. 'Hawaiian Umbrella Tree'). It is my hope that they will help you and others to see what a healthy root mass on this species can look like when planted in a proper mix.
Aggressive root-pruning done on June 25, 2009.
[img]https://i62.photobucket.com/albums/h109/Big_Vine/Plants/IMG_5025.jpg[/img]
[img]https://i62.photobucket.com/albums/h109/Big_Vine/Plants/IMG_6187.jpg[/img]
Same plant ^^^ on October 27, 2009.
This root growth was generated in just 4 months!
The 'soil' was comprised of lava rock (1/16" to 1/4" particle size) with peat as the organic component.
BV
The following photos were taken from a healthy Schefflera arboricola (a.k.a. 'Hawaiian Umbrella Tree'). It is my hope that they will help you and others to see what a healthy root mass on this species can look like when planted in a proper mix.
Aggressive root-pruning done on June 25, 2009.
[img]https://i62.photobucket.com/albums/h109/Big_Vine/Plants/IMG_5025.jpg[/img]
[img]https://i62.photobucket.com/albums/h109/Big_Vine/Plants/IMG_6187.jpg[/img]
Same plant ^^^ on October 27, 2009.
This root growth was generated in just 4 months!
The 'soil' was comprised of lava rock (1/16" to 1/4" particle size) with peat as the organic component.
BV
Big Vine, that Scheff looks very healthy. Nice going. I have some cuttings rooting right now. I've got them in a mix of bonsai soil (70%) and loam (30%).
[img]https://i956.photobucket.com/albums/ae50/marsman61/Bonsai/Hunts%20Schefflera/c66321e4.jpg[/img]
There are 5 cuttings in this pot and I have another pot as well with cuttings. And two long cuttings rooting in vases with water. I used rooting hormone with all of them.
[img]https://i956.photobucket.com/albums/ae50/marsman61/Bonsai/Hunts%20Schefflera/c66321e4.jpg[/img]
There are 5 cuttings in this pot and I have another pot as well with cuttings. And two long cuttings rooting in vases with water. I used rooting hormone with all of them.
Wow! I didn't know that Scheffs were so agressive with root growth. Now that I have something to compare it to, my root system does look very sparse. You would probably have to have a regular pruning schedule with your roots, from the looks of it? I have lots to learn in terms of soil composition, so thank you for the pictures and your secret blend 
Especially in that small of a pot, yes!Sunnydaze wrote:You would probably have to have a regular pruning schedule with your roots, from the looks of it?
I have since moved it to a much larger training pot to accelerate growth and get the trunk more to my liking.
You are most welcome!Sunnydaze wrote:I have lots to learn in terms of soil composition, so thank you for the pictures and your secret blend
I've actually switched to my own soil mix since those photos were taken, and I now use Florida limestone (might need to be careful about too much alkalinity, but the Scheffs seem to love it) as a substitute for the lava rock and coconut husk as a substitute for the peat.
I turned to FL limestone because it is readily available locally in appropriate sizes and is dirt cheap when compared to lava rock (but if the lava rock were cheaper and easier to find, I'd stick with it instead because it is a lot lighter and also more porous than the limestone). I switched to coconut husk (NOT the really fine stuff that turns to 'sawdust mush' when wetted) because it is much chunkier than the peat and a more suitable organic, in my opinion.
BV