Lethbridge Herald, The (Newspaper) - January 14, 1975, Lethbridge, Alberta
LETHBRIDGE HERALD Tuesday, January 14, 1975 Those black blotches on the studs in your basement are not an indication the building is about to collapse around you but they could be a source of allergies. Two Lethbridge researchers delved into the problem when the blotches appeared on two-by-four studs in one of their homes. The cause was determined to be sap stain fungus, a common problem on wood and wood products when the product has not been properly dried. Graham Bell, a micrpbiologist at the Lethbridge Research Station, noticed the blotches on wood in his Lethbridge home and more on an inexpensive bed suite his children were using. His microscope examination indicated the cosmetic construction problem was caused by a fungus which lives in the sap of growing trees. The fungus, ceratocystis, begins when trees are growing in the forest. The fungus lives within the tree in the sap in a white vegetative form. But when the tree is cut down or dies, the fungus moves to the surface, turns black By RIC SWIHART, Herald Staff Writer and enters a reproductive stage. Mr. Bell said timber tends to be cut when damp. The fungus infection is spread in the lumber mill by the saw blades. When the lumber is stacked, usually prior to being properly dried, the fungus finds an ideal growth condition. It is-most common on construction studding. Two Lethbridge carpenters said they have seen entire two-by-four studs covered with the fungus. "Black as coal and they say. They stress the fungus does not reduce the strength of the wood but makes it look horrid. Because it is a fungus, it emits spores into the atmosphere. A Lethbridge physician and skin specialist told The Herald the fungus which causes the black blotches is not one of the common spore producing fungi that can produce symptoms of asthma and hay fever. Because this fungus emits spores, it may contribute to hay fever and asthma problems, he said. The fungus can be controlled on wood which can be reached, said Gil Croome, another researcher. Fungicide can be applied to stop the spread of the fungus. But to remove existing fungus from boards, either in the home on on furniture, the wood must be sanded. This should only be done in places where the wood can be seen and is objectionable to the homeowner or in the event the fungus contributes to an allergy in the home. About the only way to ensure that a home doesn't have fungus spores is to use only stain-free kiln-dried lumber, according to one carpenter. This usually means selecting only the top grade lumber since the fungus affected boards are docked a grade or two, depending on the degree of the infection. Customers check the underside of the fur- niture they are buying for the fungus, ac- cording to one researcher. He claims the fungus is not as prevalent on more expen- sive furniture because of the higher use of better quality wood.