Heart Shakes

Heart shakes in lumber refer to cracks or separations that occur along the growth rings of a tree, typically near the center of the trunk where the heartwood is located. These types of cracks are also known as radial shakes, as they run radially along the tree trunk.

Heart shakes are caused by natural stresses that occur within the tree as it grows and ages, such as changes in temperature, moisture, or wind load. These stresses can cause the wood fibers to separate or crack, resulting in the formation of heart shakes.

Heart shakes can vary in size and severity, ranging from small, barely visible cracks to larger, more significant separations that can compromise the strength and structural integrity of the wood.