Bonsai No Leaves
This is known as leaf burn.
Bonsai no leaves. Expect for your bonsai to. Strong foliage loss due to disease occurs much less frequently in bonsai trees than is often assumed. Use sharp sterile pruning shears to remove any areas of the bonsai that are cannot be saved such as dead or broken branches and wilted. Good photos samples of leaves or needles are very helpful for the analysis.
If you suspect an illness such as pine wilt ask a specialist. A bonsai is a gift for life. Alternatively like the conifers under watering a deciduous tree will caused the leaves to dry up and eventually fall off completely. Be sure to act quickly as such infections can spread quickly or even leap from one bonsai onto other nearby plants.
In doing so you force the tree to grow new leaves leading to a reduction in the size of leaves and an increase in ramification. A few months of overwatering will lead to root rot only visible in the tree losing strength and dropping its leaves. Bonsai loses leaves or needles due to disease. How to revive a dying bonsai tree.
This technique should only be used on deciduous trees healthy enough to withstand this demanding technique. Overwatering is a common reason when the indoor bonsai is planted in poor soil that retains too much water. If your bonsai is losing its leaves in the wrong season that s almost always a sign of a mold or fungal infection. For deciduous trees like maples discoloration in the foliage could be caused by continued exposure to the afternoon sun.
Once again a round of fungicide is your only option here for saving the tree.