Q. Our Chinaberry tree
broke off after the winds a few days ago. I saw all this dark wood inside the
tree and it was dried out. This tree has withstood way stronger winds than what
we just had which concerns me. Is this anything to be concerned about?
A. The inside of any tree,
including Chinaberry or Texas Umbrella tree, is virtually dead regardless
whether it is healthy or not. This dead area is called the “heartwood” of the
tree. The only living part of its trunk is a small cylinder of wood surrounding
the heartwood and just under the bark. This is called the “sapwood”.
Heartwood
is darker in color than sapwood. Because it is dead, heartwood can rot without
damaging the sapwood. This rotting of the heartwood can leave the tree hollow
on the inside. But rotting of the heartwood can also make the tree weaker and
prone to breakage during strong winds.
As
a tree gets bigger it grows in two ways; it grows taller and limbs become
longer called primary growth. It also gets "fatter" or bigger in
diameter. This growth is called secondary growth. Secondary growth is
responsible for sapwood remaining just under the bark as the tree gets “fatter”.
As sapwood grows outward it leaves behind the dead heartwood in its interior.
The
tree can live without its heartwood but it cannot live without its sapwood. But
loss of heartwood can leave the tree weakened. If the tree can cause damage
when it breaks, then consider removing it.
The “dryness” of the wood may be "dry
rot" as the heartwood is disappearing or rotting away. Frequently interior
rotting of the tree is accompanied by soft growths attached to the trunk. These
are a type of mushroom called “bracket fungi” or conks and are strong
indicators that some form of rotting is occurring.
If
you want to keep the tree strong, make sure it receives enough water and
fertilize it once a year. If it does not, the tree becomes weaker and much
easier to damage during strong winds.