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Lumber Stains: Cause and Control. Lance Johnson ISK Biocides, Inc.. Memphis, TN. Lumber Stains: Cause and Control. Types of Stain: FUNGAL (Microbial) NON-FUNGAL (Non-Microbial). Lumber Stains: Cause and Control. Types of Stain: FUNGAL (Microbial) Mold Sapstain.
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Lumber Stains:Cause and Control Lance Johnson ISKBiocides, Inc.. Memphis, TN
Lumber Stains: Cause and Control • Types of Stain: • FUNGAL (Microbial) • NON-FUNGAL (Non-Microbial)
Lumber Stains: Cause and Control • Types of Stain: • FUNGAL (Microbial) Mold Sapstain
Lumber Stains: Cause and Control • NON-FUNGAL (Non-microbial) • Enzymatic “Gray” Stain • Sticker Stain • Iron Stain • Mineral Stain
Lumber Stains: Cause and Control • Fungal (Microbial) Stain
Lumber Stains: Cause and Control • A primitive plant with no stem, roots, leaves, chlorophyll. • DOES have a Hypha (Hyphae) body (threadlike strands). • DOES have Fruiting Structures which produce Spores (Seeds).
Lumber Stains: Cause and Control CONDITIONS FOR FUNGAL GROWTH: • Fungi must have oxygen • Temperature range of 35-130 degrees F • Moisture content of 20% to saturation • Food source
Lumber Stains: Cause and Control • MOLD and SAPSTAIN FUNGI: • Utilize readily available nutrients (starch, sugar, protein, and fats) stored in the sap wood (parenchyma cells)
Lumber Stains: Cause and Control • MOLD FUNGI
Lumber Stains: Cause and Control MOLD FUNGI: • Form SPORES of various colors on surface of wood, HYPHAE are not pigmented. • Discoloration does NOT appear below surface of wood
Lumber Stains: Cause and Control • SAPSTAIN FUNGI
Lumber Stains: Cause and Control SAPSTAIN FUNGI: Pigment of HYPHAE cause discoloration below the surface of the wood.
Lumber Stains: Cause and Control • Require at least 20% wood moisture content
Lumber Stains: Cause and Control • Cause little loss of wood strength
Lumber Stains: Cause and Control • Optimum temperature = 75-85 degrees F
Lumber Stains: Cause and Control • Fungal SPORES become air-borne and are deposited on freshly cut lumber. Growth starts very quickly • These SPORES also contaminate sawmill machinery and equipment • Wood debris around a mill yard provides an excellent source of fungal SPORES
Lumber Stains: Cause and Control CONTROLLING FUNGAL STAIN: • Proper Handling of raw material • Oxygen depletion • Envelope biocide treatment • Proper drying practices
Lumber Stains: Cause and Control Proper Handling of Raw Material: • Rapid utilization of logs • Short water-spray storage • First IN – First OUT • Encapsulation of logs
Lumber Stains: Cause and Control Oxygen Depletion: • Log ponding • Water sprays
Lumber Stains: Cause and Control Envelope Biocides Treatment: • Provides relatively inexpensive short-term protection by coating surface of the lumber with biocide chemical • Applied using dip or spray method • Relatively short dipping time
Lumber Stains: Cause and Control • Envelope Biocide Treatment (Cont.): • Will not kill insect larvae feeding within the wood • Will not control non-microbial enzymatic “gray” stain or mineral stain
Lumber Stains: Cause and Control Biocide treatment should be applied immediately after sawing!
Lumber Stains: Cause and Control • When choosing a product: • Review the toxicity package • Possibly field test at your site • Review the independent Efficacy data • Look at QC methods for wood & solution • Remember… It should be a partnership between the log supplier, the sawmill and the chemical producer to produce the best product
Lumber Stains: Cause and Control • Yellow Poplar – Six Weeks in Plastic
Lumber Stains: Cause and Control • Treatment Methods • Across-the-chain tank • Bulk dip tank • Spray
Lumber Stains: Cause and Control Recommendations for a Biocide Dipping Facility: • Coated, lined, or stainless steel dip tank – iron stain • Agitation – debris accumulation • Covered – rain dilution
Lumber Stains: Cause and Control More Recommendations: • Drip pad – excess biocide recovery • Tank containment
Lumber Stains: Cause and Control Chemical Safety Precautions -Follow chemical manufacturers material safety data sheet
Lumber Stains: Cause and Control Treatment of lumber with biocides is NOT a substitute for proper drying practices!
Lumber Stains: Cause and Control Good Air Drying Facility: • Well drained • No weeds or debris
Lumber Stains: Cause and Control • NON-FUNGAL (Non-Microbial) STAIN