What is the difference between “Green” and “Dead Standing” timber? Dead standing timber are trees that have died because of aging, drought, a lowering of the groundwater level, forest fires, widespread fungal diseases, or infestation by harmful insects. Dead standing timber typically dries in the forest as a standing tree with the bark on it. “Green” refers to harvesting live healthy timber which is then processed sufficient to removed the bark and roughly size the timber prior to drying.
With the exception of fungal or insect kill timber, Dead Standing timber should be harvested as close to green as possible to ensure the best product. The longer trees stand in the forest, particularly with the bark on, the more susceptible they are to decay. In the instance of fungal or insect kill dead standing timber should only be harvested once the tree has dried sufficient to ensure the insects or fungus no longer contaminate the tree.
Another aspect of dead standing timber that must be considered is the moisture content of the timber. Moisture content will vary from one log to the next depending on the length of time the tree has been dead. Having consistent moisture content below 19% in your logs is essential to minimizing the shrinkage and setting of log walls. Moisture meters should be used to verify moisture content of dead standing trees the same as with green harvested trees to ensue a consistently dried product.
Green logs will require some type of drying method in order for it to meet industry standards of 19% moisture content. Typically this involves removing the bark, rough sizing the log and then kiln drying, curing or using a hybrid of the two. Kiln drying involves forced heating and air movement to dry the material. Curing means allowing the log to air dry. Kiln drying is much faster but typically does not result in as consistent of a moisture content throughout the log. Curing requires a longer period of time but typically results in a more consistent moisture content throughout the log. Curing can be a challenge for many mills due to the large amount of inventory necessary to allow sufficient time for the timber to dry.
A “Green” harvested log processed correctly and cured will result in a log home that is consistent in its moisture content through and through minimizing shrinkage as a result of acclimatization drying. With “Green” cured logs you can be confident the logs are in excellent condition and have not began to decompose or been exposed to unnecessary stresses. Also, when you begin construction you know your home is ready to build because your manufacture will have readily available inventory that has been air dried over a long period of time.