Wood Characteristics - Drying Effects

Air Check

• Occurs if too much moisture is removed from the outer portion before the inner portion has lost moisture and shrunk
• Shown in Red Oak with air check or surface check

Honey Comb

• Not natural, but common
• Occurs when kiln temperatures are raised before the lumber core moisture has been lowered sufficiently
• Example shows end grain and lumber ripped in half to expose the severe interior honeycomb

Shake

• Also called ring shake or wind shake
• Caused by bacteria weakening the area between growth rings
• Bacteria may have a vinegar or rancid smell prior to drying
• Shown in Red Oak
• Flatsawn portion shows typical shake
• End grain portion shows ring failure

Splitting or Cracking

• May occur in any wood type
• May be minimized by proper end coating of logs or lumber before drying
• Shown in Red Oak