Artillery fungus is tough to fight

[Beth n Rod]

Gene Austin
Philadelphia Inquirer
March 3, 2001

If your siding, car, fence or any other surfaces around your house have broken out with a rash of black or dark-brown specks that do not want to come off, you are probably at war with something called artillery fungus.

It has become increasingly common in recent years, according to experts who have been seeking ways to control and eradicate it.

Artillery fungus, also called shotgun fungus or Sphaerobolus stellatus, usually originates in wood-chip mulch that is used around shrubs, flowers and other plants. Wet, rotting mulch breeds small mushrooms that shoot off spores for distances of up to 20 feet. The spores, which are sometimes mistaken for insect waste or bits of tar, cling tenaciously to surfaces such as house siding.

"It's just like Super Glue," said Don Davis, professor of plant pathology at Pennsylvania State University's College of Agricultural Sciences. Davis and Larry Kuhns, professor of horticulture, have been leading a five-year study of the fungus, and they expect the study to continue for several more years.

Davis said he gets 20 to 30calls a week during the fungus' most active seasons - generally spring and fall when temperatures range between 50 and 68 degrees. Callers are steered to Davis and Kuhns through the college's Internet site: http://www.cas.psu.edu/docs/casdept/...mulchfun.html.

Davis said the rapid spread of the fungus and the growing number of fungus-damaged homes appear to be linked to the growing use of mulches made from recycled hardwood scraps and tree stumps.

Homeowners can take a key step to control artillery fungus by cleaning up wood-chip mulch around the house and disposing of it before the shooting starts again in April or May.

Here are some additional tips:


• Control. Bark mulch appears to be more resistant to the fungus than wood-chip mulch. Davis said pine-bark chunks seem to be the most resistant, and cedar, redwood and cypress mulch also appear to be resistant. "Even these mulches should be replaced every few years," he said.


• Davis said stone mulch (usually small, decorative stones) "is the ultimate answer" to artillery fungus. Black plastic, held in place by stones or boards, is also safe, and some homeowners are getting good results with leaf mulch.

Kuhns said fungicides do not work well because "it's hard to determine when the mulch becomes infested, making the timing of the application . . . difficult."


• Insurance. If your house is damaged by artillery fungus, check with the agent handling your homeowners insurance. Most policies do not cover damage from fungus or mildew, but some do.


• Power-washing. Once the fungus becomes attached to a surface, even power-washing is not effective unless it is done within a few weeks of a fungal outbreak.


• One power-washing expert said he was able to remove the fungus using 200-degree water, with water pressure of 3,000 pounds per square inch, but this combination of hot water and high pressure can damage some types of siding.


• Scraping. Artillery fungus can be removed from windows by scraping with a razor blade. Scraping also can remove some of the black specks from smooth siding, but several homeowners who tried this reported that a brown residue remains and can't be removed. Scraping can gouge vinyl and painted siding.


Gene Austin welcomes readers' questions and comments, but he cannot give personal replies. Address correspondence to Gene Austin, the Philadelphia Inquirer, P.O. Box 8263, Philadelphia, PA 19101.

[SQUEEKY]

thanks
will be adding this to my customer education literature.

[william gurley]

I got the answer.FINGERNAIL

[John Orr]

I got the answer.FINGERNAIL

If the spore has been on siding for any length of time, a fingernail will not work. It will remove the hard shell, but the stain remains. If a fingernail removes the stain, its still fresh, and those are a small percentage on most homes.

[Beth n Rod]

Agreed John. Usually if you can get to them within a few weeks of their first being attached you can get them off for the most part, but after that, they are near impossible to remove by normal house washing methods. It calls for scraping off the nodules and applying a sodium hydroxide solution followed by a bit of brushing and then applying a Sodium Hypochlorite mix to lighten the stain.
Depending on how long it has been there will determine the results.
On vinyl siding depending on certain colors and the quality of the siding itself artillery fungus can be removed almost completely and on others a stain will still be present.
On aluminum siding you will have discolorations in the paint no matter what you do because of the enzymes in the spores that are used to attach themselves to the surface they land on which destroys the coating in the process. It is not to different from cyanoacrylate in super-glue in the way it works deliberately by emulsification and after the action is complete it re-hardens to form a bond.
This is the nature of what we are up against when we are trying to clean siding.

Rod!~

[John Orr]

I have started rinsing with carnuba wax. The hope is that this may make it easier to remove future spores.

[william gurley]

The fingernail was joke.Ive been dealing with the fungus here in sc for a while also.when i look at a job i just explain to the customer what it is.

[Don L]

There has been an explosion of artillery here.According to several university coop ext's(U of Maryland,Cornell,both heavy hitters)there is NO chem that will touch it.
Rod,have you had any problems with the hypochlorite on vinyl?
Jon,good idea w/ the carnuba.What kind of results have you had?
The strongest division of my biz is window cleaning,that is easy to remove(razor),but the damage to vinyl is rampant.To find an answer to this problem that is effective,and cost effective would be a great boon to any of us.
My recent tack has been education of my customers.Informing them that the spores are activated by temps that are between 65-45 degrees.If you catch the spores before they set,it is possible to pw them off.Have fun keeping track of this.The other point is that they should consider switching mulch.To stone or bark based mulch.I am doing this off the top of my head,hope I am on target,but accurate info is available with a brief search.
This stuff is a real PITA.
Let's figure it out.

[Beth n Rod]

Rod,have you had any problems with the hypochlorite on vinyl?

It can be a problem if left on too long at high concentrations. It will cause the siding to turn dull.

Rod!~