Gardening With Chemically Pressure Treated Lumber – Pros and Cons

Source Document: Choose Wood Materials Carefully To Prevent Termites and Rot Authored by – Barb Ogg, PhD, Extension Educator – University of Nebraska-Lincoln in Lancaster County
Web site:
444 Cherrycreek Road, Suite A
Lincoln, NE 68528

In my research on chemically treated lumber products, I have come to the conclusion that in general, pressure treated lumber that has been sold in the past 8 to 10 years is safe to be used in your garden if you take a few simple common sense safety precautions.
**Chemical migration out of pressure treated lumber into the soil does not seem to be of much concern.
* Do not allow root crops like carrots, beets and potato’s come in direct prolonged contact with pressure treated lumber.
* Wash anything including your hands that have come in direct contact with CCA, ACQ or CBA pressure treated lumber.
* Use eye protection (glasses) and a paint filter type respirator (filter) when cutting, sawing or milling pressure treated lumber.
* Wear gloves when handling pressure treated lumber.
* Do Not burn pressure treated wood in your home/shop stove or fire place. Never, Ever use this lumber in your BBQ grill or meat smoker.
* Do Not use pressure treated lumber for indoor construction projects, it is designed to be used Only for construction projects.

Pressure-treated lumber. Pressure-treated lumber is highly resistant to decay and insects. Through a series of pressure and vacuum cycles, wood preservative is forced deep into wood pores, forming a chemical barrier against termites and decay.

Many people are familiar with green Chromated Copper Arsenate (CCA) treated wood. It has been widely available since the 1970s; literally millions of decks have been built of CCA-treated wood. It is very resistant to termites and decay, but because arsenic is a known carcinogen, this wood has not be available for residential use after January 2004.

The decision to phase (out) CCA-treated wood for residential structures has people asking what to do with existing structures made of this material. The EPA does not suggest tearing down structures made of CCA-treated wood. According to the EPA, people should take common sense precautions, especially when it comes to children. Kids should wash hands after playing on structures and keep food from direct contact with CCA-treated wood.

* The EPA has stated that applying a penetrating oil finish as needed to pressure treated wood surfaces (that have human contact) can lessen or eliminate human and animal exposure to CCA in existing decks. Studies done to date show a dramatic decrease in the amount of arsenic at the surface of the wood for periods up to two years when compared with unsealed wood.

* Safety rules regarding common sense cleanup should be sufficient. However, these newer products are extremely corrosive to steel and aluminum. Fasteners (nails, screws and staples) and construction hangers/ties should be rated for use with the new wood. Any aluminum flashing should be covered with an impervious layer of a non-corrosive material such as tar paper or non-permeable plastic sheets to prevent contact with the wood.

Alkaline Copper Quaternary (ACQ). This treated wood has been used successfully for more than 10 years and has the same green look as CCA treated wood, but does not contain arsenic or chromium. It has been found to have performance characteristics similar to wood treated with CCA. Preserve®, Preserve Plus®, NatureWood® are brand names for ACQ pressure-treated wood.

Copper Boron Azole (CBA). CBA is a copper-based preservative with an organic fungicide. The treated wood is a dark honey brown color and turns a silver-gray after it weathers. Wood products treated with Copper Azole have been used successfully since 1992. Wolmanized Natural Select™ is a brand name for CBA-treated wood.

Not from the USA. Please leave me comment about your home town and country.

Why is common sense so uncommon?
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