Hello I have discovered a soot-like, charcoal colored , paper thin film adhearing onto my Camellia shrubs...what is this? and what is the cause of this? I can remove it by rubbing it off the waxy leaf surface...I am stumped and horrified by this unsightly appearance...
Hello Daniel, Due to lack responses to my thread..camellia... thought that it should be removed from the system, however, the topic may be of value to others with similar experiences with this mold?
I can't recall a single thread I've ever removed that was on-topic and with potentially insightful discussion - nor would I want to start doing so, as my workload on the forums is only going to increase in the near future. Best to just let it be, it'll either scroll down or someone will come along and post a lengthy response.
Adding to previous comments, what to do for this fairly common problem is look for source of sweet, sticky excretions ('honeydew') that sooty mold is growing on, eliminate that. Aphids on trees above (such as birches or Norway maples) are likely perpetrators; camellias specifically can be prone to scale insects that will become rather large and visible on stems and leaves.
I did not know there was a sense of urgency for this condition. It may help for us to see some photos of your Camellia to better know what has caused what you feel is an unsightly problem. Most likely it is a sooty mold that has come about from as a result of a scale insect. Then again it is not out of bounds for your Camellia to have black algae either which can come about from high moisture and lack of direct light. It is common this time of year for us to see a sooty mold on many of our South facing leaves on our Citrus. The mold as a result of honeydew also caused by scale will turn a more intense black color here due to air pollution from smoke particulates usually from people using wood stoves or their fire places on the valley floor. The mold is easy enough to wash off with a hose but depending on how widespread this condition is a high pressure hand sprayer with water and a little bit of vinegar added will help wash the mold off and keep it off. The scale is another issue as there must be a lot of it for the sooty mold to be so much of a problem. In this case an insecticidal soap added into the mixture along with water and vinegar will help but you will also have to thoroughly spray the Camellia including the undersides of the leaves to have any affect on the Cottony Cushion scale that you probably have. The sooty mold is the least of your concerns as it is the insect and how difficult it can be to suppress that will cause you much more trouble later if left untreated. Even with some organophosphate insecticides this insect can still become hard to stop if the insect has become too established. Water sprays and insecticidal soaps may not have any real impact on this scale if the infestation has gotten too far along. If the insect cannot be treated or at least slowed down by a low grade enhanced dousing of the mixture then you may have to use a high powered insecticide just to save your Camellia. Yes, in that sense there is indeed a sense of urgency here. Even if you have a black algae which I’ve seen on Camellias grown in the foothills in the nearby Sierras your only real recourse may to be hand wipe each and every leaf and then go in and use an algaecide spray which will not be of any benefit to your plants root system as you risk killing the plant in order to try to save it. Jim
i would never use "organophosphate insecticides" again, i am sure it effected my health....anyway back to your camellia, did you discover wether it was aphids or scale insect? ooops, nearly forgot, if you are considering using organophosphate pesticides, get your tolerance level checked by a Doctor.
I am not advocating the use of any pesticide for what I suspect is probably scale damage. Even today I used a hand sprayer with a mixture of water and some vinegar for a spot of Cottony Cushion scale I found on our Mexican Lime. All I am saying is that once this scale becomes established it can be a real bear cat to get rid of. In some cases even some organophosphate sprays may not get rid of it soon enough and even then this scale can still come back on us. Timing of our water sprays is far more important in dealing with this pest for early preventative action. Besides, Camellias like having their "faces" (surface of the leaves) washed after they bloom and all through a dry and dusty Summer here. So, we can accomplish more good than we thought just with water alone. Jim
Wow, as I become more familiar with this amazing web site, I would just like to say a Big Thankyou for everyones' expert advice and very insightful comments. Back to my Camellia, I manually removed the aphids, and the tender growth up to Christmas, I can see where the insects secrections would attract the mold/ black papery film , especially on the north facing leaves. I will be more diligent when it comes to maintaining the health of my 30 year old shrubs...now if this cold spell would head back northward...happy pre spring gardening to all.
