Treating Trillium smut (Urocystis trillii)

[Maggi Young]

Useful post from John Aipassa, on a SRGC Facebook page:

John Aipassa

Last year I made a post about treating Trillium smut (Urocystis trillii) using Trichoderma without destroying your diseased Trillium plants. I asked if there was interest in my way of treating.
I am going to explain this method as I now get more and more pm requests of sharing my experiences. So here we go.

The reason why I have posted last year is a fellow garden friend, who destroyed all her infected Trillium plants after a smut infection. Everything was binned and that broke my Trillium heart. This is not necessary, if you know what the disease is and how to treat and deal with it.

Trillium smut is a fungal disease. In a contaminated spot the fungus' spores are present in the soil and will contaminate a Trillium when the plant pushes through the soil when emerging. An infected plant will develop lesions on the stalk or on the leaves, which will develop new spores. Untreated plants will eventually look awful and will collaps during the season without kiling the rhizome. Dreadful is the development and spreading of new spores, when untreated.

So my treatment is this and it focuses on getting rid of the fungus and not the entire plant.

If I see a lesion develop and know my plant is infected, I take a paintbrush and brush the full stalk and especially the lesion with pure vinegar. I use apple cider vinegar. I also spray the leaves and flowers with pure vinegar without missing a spot. After a few minutes I will rinse the plant with fresh water to get rid of the vinegar. I then sprinkle the plant from above with water where Trichoderma (harzianum) is mixed in. You can also try to spray, but the Trichoderma clogs the spraybottle quite quickly.

When I am (too) late and the lesions made the plant look dreadful, I will break the full plant off at the ground level or even up till the rhizome leaving the rhizome itself in the soil. You can add calcium to the soil later, if you worry about a low pH because of the vinegar.

I will then focus on treating the spores in the soil. The spot where the Trillium is growing will be drenched with Trichoderma. Mix a generous amount of Trichoderma in the top soil and water extensively. Makes sure you drench the spot where the stalk comes out of the ground, it will go straight to the rhizome. Repeat this procedure for two or three days.

The next year you will most probably get rid of the smut at that particular spot. I did.
You won't get rid of the disease in your garden entirely. If you have had at least one diseased Trillium, there is a very good chance the spores have spreaded throughout your garden already, increasing the risk of contamination for your newly planted healthy Trillium.

 I believe you never get rid of all the spores in your garden once the disease has reached it. A reality you will have to deal with. I won't swop or sell any of my garden Trilliums for this reason unless the plant is treated with Trichoderma, but I am still very reluctant to do so. I do give seeds, but only after I have treated the berry with vinegar first before opening the berry and get the seeds.

Although my garden is now smut free, I think there will always be a chance, that the disease can return because of the spores in the garden, if you do not treat the new spot, where your newly bought or replanted Trillium will be planted. That spot can have spores blown in to. Treat every new spot the same as I have described above before planting a Trillium there.

I have experienced the return of smut on one or two plants only one or two times now, but never on allmost all of my clumps as I have experienced many years ago, after I got an infected Trillium kurabayashii from a reputable source. I got so many infected beautiful specimens, that I looked for another solution other than binning. It would be the loss of my collection otherwise.

 I got help of a fellow Trillium lover, who is also an agronomist. He guided me through this method. He suggested using a chemical anti fungus in combination with the Trichoderma at first, but I wanted it to be as organic as possible. So I tweaked and used vinegar instead.

The method has worked for me. The last 5 years my Trilliums are all free of smut, also the ones that have been infected before. The plants look healthy and no lesions have developed since. I haven't binned any of them. That would be a sorry thing to do as you (might) have the spores still in your garden soil. Getting rid of a plant does not guarantee getting rid of the spores. I might get another infection in the coming years, but with treatment, I can treat the infection and get a healthy plant back the next year.


A treatment well worth trying - and perhaps on other smut diseases, too.
Thanks, John!

[Vinny 123]

I am waiting for the first claim that vinegar, of any variety, cures cancer. From a condiment to the world's answer to every known ill of every lifeform on earth in 30 years or so. Amazing stuff.

Lots of genuine science-based information about Trichoderma on the www though.

[Maggi Young]

I've never been shocked at the myriad uses for vinegar - it's a very readily available mild acid and has been around for a very long time - no wonder it's been  used for so many things, other than making one's fish and chips tasty!

[partisangardener]

Thank you.

[Vinny 123]

I've never been shocked at the myriad uses for vinegar - it's a very readily available mild acid and has been around for a very long time - no wonder it's been  used for so many things, other than making one's fish and chips tasty!

If only there was the tiniest shred of science-based evidence for even 1% of the claims.
As for any insistance that it be apple or malt, or wine, or any other version.....................................

[MarcR]

Thank you.

Thank you, Maggi!

Many years ago I had to deal with mold on the walls of my apartment. A vinegar wash before repainting solved the problem.  It is not surprising that vinegar works as a fungicide on plants.  A mild solution of Sodium hypoclorate [laundry bleach] also works well with no harn to the plants.

[ashley]

Concentrated vinegar (acetic acid, 80%) is an effective fumigant for e.g. beekeeping equipment, and destroys spores of the highly infectious fungus Ascosphaera apis that causes chalkbrood disease in honeybee larvae.  Therefore it's quite possible that lower concentrations as tolerated by plants might limit or control fungal infections.

Bleach (sodium hypochlorite, 0.5%) is also used by beekeepers as a general sterilizing agent against pathogenic fungi, microsporidians & spore-forming bacteria.