Pressure-Treated Southern Yellow Pine
Pinus palustris (Longleaf), Pinus echinata (Shortleaf), Pinus taeda (Loblolly), Pinus elliottii (Slash) • Softwood
Grain Pattern
Straight to slightly wavy with distinct, coarse transitions between earlywood and latewood; characteristic flat-sawn cathedral patterns are visible where the surface is worn; large growth rings indicative of fast growth.
Color Description
Naturally light yellowish-brown but currently heavily weathered to a silvery-gray and dark charcoal-brown due to outdoor UV exposure; traces of greenish chemical tint from initial copper-based pressure treatment may exist in protected fibers.
Hardness Rating
690 lbf (Soft to Medium-Soft); among the hardest of domestic softwoods.
Durability Rating
Very Durable (due to chemical treatment); the underlying wood is naturally non-durable to decay/insects, but the chemical infusion provides high resistance to rot and fungal attack.
Common Uses
Outdoor decking, stairs, boardwalks, fencing, landscaping, and structural framing (posts and beams).
Geographic Origin
Southeastern United States (major growing regions from Virginia to Texas).
Market Value & Sustainability
Estimated Market Value
$1.50 - $3.00 per board foot (varies by treatment grade and lumber dimension).
Wood Age Estimate
10-20 years; based on the deep silver-gray oxidation, surface checking (cracks), and biological staining indicative of prolonged outdoor exposure without recent maintenance.
Sustainability Status
Highly Sustainable/Not listed on CITES; widely available with FSC and SFI certification; grown in managed timber plantations.
Workability
Easy to work with power tools; can be gummy due to resin content; requires specialized fasteners (hot-dipped galvanized or stainless steel) to prevent corrosion from the pressure-treatment chemicals.
Notable Features
Distinctive resinous scent when cut; contains copper-based preservatives (ACQ or MCQ); high density for a softwood; prone to warping and checking if not sealed.
Finish Recommendations
Solid or semi-transparent oil-based deck stain after thorough cleaning and sanding; needs a finish with UV inhibitors to prevent further silvering.
Identification Confidence
High; the structural application as stairs/decking, the prominent coarse grain of the latewood, and the specific graying-patina are diagnostic for Southern Yellow Pine in an outdoor setting.