Look closely at a dead tree where the bark has peeled off. The outer layer of bark is important to protect the tree from weather, fire and disease. Inside of this layer is the cambium, a layer that produces growth in the tree, one ring added for each year of growth. During dry years or years where the tree was stressed, the growth ring might be thinner than other years. If you look carefully where the bark is missing, you may see a maze-like pattern carved into the wood left by a grub or beetle as it eats its way through the wood. These tracks are called galleries and can be seen in the layer called the sapwood, a layer of wood that transports nutrients and water. Many different types of insects lay eggs in and/or feed on the wood of trees under the bark. Inside of the sapwood is the strong, older ‘dead’ wood in the middle of the tree called the heartwood. The denser heartwood provides support for the branches, shape for the tree and lumber for many of our homes and businesses.