Promoting blue stain
How to promote this visual effect in a stack of red pine. March 21, 2002
How do I speed up staining in red pine logs? Particularly the blue stain.
70+ degrees and high moisture, you already have the food and fungus. I had a log home customer who specifically requested heavily blued logs from the air-dried supplier. After a rain and 90+ temperatures it got pretty funky. Still, he was bragging about the beauty of his logs till they did a documentary on "killer molds" on TV. I don't think they are the same but it sure took the wind out of his sails.
From the original questioner:
I have one customer that would buy the worst looking pile I could find every year. He would have it kiln dried and planed. It is the most beautiful paneling I have ever seen. The kiln drying part would probably be pretty important. What if I stacked it green without stickers and covered it with a black tarp?
I saw blue stain for a few people and get my best stuff from dead standing timber. I "ringed" several trees last fall where I was cutting and the trees are now dead. I have tried to cut the logs and leave them in the shade but the affects were not as good. You can saw and sticker stack in the shade and spray with water and get a mold and some blue stain but I feel that it is not as good as dead standing.
In SYP, heat and humidity do the trick. Let your logs lie in the dirt and get rained on for a month or two or wait 2 weeks before you sticker cut lumber. It seems to affect only the sapwood. I hear they are making flooring out of it. If the stain gets black, the lumber gets brittle.
Here in NH, more than a week of summer heat and humidity equals blue stain in sapwood. Leave the cut lumber dead stacked for a few days and make sure to leave some bark attached.
From the original questioner:
I have 100,000 board feet in log form piled out front. It has stained, but not enough for me. It has come in from the ends about 6 feet, but they are 27 foot logs. This spring will be one year, and I am afraid to let them set another year.
The guys saying to saw and dead stack are probably right. If the spores are floating around everywhere it seems to me that exposing more surface area would be the way to spread the infection the fastest and most evenly. My wife makes this awful compost brew to put on the veggie garden. If you were to brew up some kind of "stumpwater" and spray it on, I wonder…
Can't help noticing the fastest staining SY pine I get is from sawing through the bark and across the board, then not sweeping off the sawdust as I make the lower cut. Dead stacking these green after that is the final fatal blow to clean lumber.
I think it's that brown dust from the bark, or maybe something from the cambium layer (sugars?) feeding the stain-causing mold. Old, warm logs are particularly bad for me. So, don't seal the ends, saw through and through (or at least don't slab the face the saw is cutting into, but let the blade drag the bark dust across the cut).
Also, I have the stain stripes on some rather dense syp heart where I either used un-dry sticks or had sufficient airflow (probably the latter}.
Regarding the killer molds, I can remember feeling bad after planing discolored wood, and thinking I smelled something menthol-like.
Do any of you notice a faint licorice smell sometimes when cutting SY pine?
About 15 years ago I tried stacking lumber on sticks in a refer trailer and closed the doors to keep in the heat. This was during the summer with no air circulating. I opened the doors about 10 days later to look and boy what a crop of mold I had growing.
From Gene Wengert, forum technical advisor:
The smell you note is some of the insecticide chemicals in the bark.
Mold does not equal blue stain. Mold is only on the surface.
Take the bark off when you expose the logs for the most rapid staining, but it will be heaviest at the ends and at the outside. Therefore, cut lumber for more even staining. It will never stain the heartwood, so avoid logs with substantial heartwood.
The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).
Comment from contributor A:
The blue stain you see is the color of the fungal cells as they spread through the rays of the wood. Spore bearing fungal cells are produced on the surfaces of the logs. Spores spread the fungus so cutting and stacking should produce more surface area and more spores. Do not let the wood stack dry out.