Technical Data

Users of lumber are probably familiar with bluestain. Some may wonder if the amount and type of stain transmitted by the mountain pine beetle affects the wood in any way. Comprehensive testing recently confirmed that beetle-transmitted bluestain has no practical effect on strength properties or gluing characteristics. Neither does the bluestain affect the adhesion of furniture finishes. The stain causes some possibly beneficial changes to dimensional stability, checking and permeability.

Blue-stain lumber is harmless to one’s health, and

does not affect the use of lumber in building construction.

Technical data provided by:

FPInnovations - Forintek Western Region

2665 East Mall

Vancouver, B.C.

Canada V6T 1W5

Telephone: 604 224-3221

Fax: 604 222-5690

Forintek Canada Corp. is Canada's national wood products research institute. Their role is to support the

forest products industry in optimizing manufacturing processes, extracting higher value products from the

available resource and meeting customer's expectations of performance, durability and affordability.

Summary of tests carried out by Forintek on blue-stained wood


Test	Number of Test Specimens Blue Stained / Non-Stained*	Results
Relative Density ASTM D2395-93 Method B	220/220	No Statistical Difference (NSD)
Bending modulus of elasticity ASTM D143 Section 8	220/220	NSD
Bending modulus of rupture ASTM D143 Section 8	220/220	NSD
Impact bending strength (Toughness) ASTM D143 Section 11	220/200	**Blue-stained wood 5% lower impact bending strength
Truss plate tension splice test CSA S347 -99 (modified)	60/60	** Blue-stained wood 6% higher grip capacity
Dimensional stability/checking Forintek test method	54 (3 Packages of 18)/54	NSD
Absorption of preservatives Dip Treatment Pressure Treatment Forintek test method	60/60 60/60	Blue-stained wood absorbs significantly more wood preservative
Gluing Block Shear Test ASTM D905-89 Delamination Test D1101-92	3 Replicates of 30 samples x 2 glue types x 2 wood types (stained/Non-Stained) 1 replicate x 30 samples x 2 glue types x 2 wood types	NSD NSD
Finishing properties Visual assesment Forintek test method Adhesive tape tests ASTM D33359-93	40 two-sided panels 80	Blue-satin can be disguised with dark finishes NSD
NSD - No Statistical Difference * These are numbers planned. Actual sample replication was usually larger. * Although these differences are statistically significant they are regarded to be of no difference from a practical point of view.