Author Topic: What's black powdery, dust type stuff on the branches and leaves of mango tree  (Read 1006 times)

sunshine2

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Hi Everyone:
Can someone please help me with an issue I have with a new Cogshall mango tree I bought.  I am in the Phoenix, AZ area.  Bought 4 dwarf mango trees with one being a nice, branched out Cogshall, 7 gallon.  When I got it home I noticed a blackish, mold type dusty residue on some of the branches and leaves.  When I rub the branches some of the stuff comes off on my fingers and when I wiped a branch with a little soapy water most of the black came off the leaves and branch.  I called the tree nursery and I was told that the dust is harmless and will not hurt the tree; that it happens on some mango trees, especially in the heat of summer.  After asking more questions they told me to bring the tree back for a refund.  But it is such a beautifully shaped tree that I hate to take it back if this dusty black stuff is harmless ...... question is, is it harmless as I was told? 

pineislander

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look up sooty mld usually there is a scale insect and/or ant nexus. Sometimes you need to look at an overhead tree to find the source.

sunshine2

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Thank you for the reply.  The mango trees at the nursery are kept under a sun filtering shade cloth.  Since its not a huge tree I tried to clean/wash off the branches and leaves with a fungicidal/bacterial soap, rinsed thoroughly, protected the pot with a plastic garbage bag.

Kada

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Usually it is from various insect excetions on the leaves and fungal.growth forms.  Control the insects, the fungi doeant come back.