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rose disease - scale?

20 years ago

I have a couple of Pierre de Ronsard roses which have been very healthy for about 6 years, apart from the occasional brush with aphids, scale and balling after rain.

Lately I discovered both had infestation of scale on the main trunks, so did the usual thing, sprayed with white oil, discouraged ants, etc. This was about 3-4 weeks ago

I just discovered that the main stems are now covered in a white fluffy substance (and I mean FLUFFY! Not like mealy bug fluffy but even more so, the strands are quite long)

Can anyone advise me as to what this is, and how to treat it? It currently looks like the rose trunks are literally covered in a layer of cotton wool. The rest of the plant appears to be OKMaria

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Comments (3)

cimmaron
20 years ago
Hi Maria-sorry it has taken so long to answer-I had an idea what the problem was but couldn't for the life of me remember what it was called.
It came to me today...MEALY BUG!
I have put a link to a bug page with mealy Bug on it but it may not look the same as what you have-apparently there are many different types of mealy bug.
Do a google image search for "mealy bug" for heaps of different pics.
regards
sandie

Here is a link that might be useful: Mealy Bug
ashke
Original Author
20 years ago
thanks sandie, that's the stuff exactly! I've had mealy mugs on other plants before, but they've been easily seen as individual bugs, never like the photo in your link, but also completely covering the stems of the rose with long cottony threads

I sprayed 'rose spray' on it a few days ago before reading your post, as it's meant to protect against scale, thrips, mealy bugs, black spot etc on roses and other ornamentals, and now most of the leaves have dropped off! It has even affected a potted hydrangea shrub behind it, which has curled up its just-opening 'flowers' and the some leaves are also dropping off.

sheesh

Maria
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cimmaron
20 years ago
Hi Maria-I don't use any sprays-they are damaging to the ecosystem and will burn the leaves on a hot or windy day.
What I do with scale (and would if I had Mealy Bug)is use a
sharp but fine jet of water to get them off.
You would need one of those hose attachments that go from full stream to fine spray.
I hope this helps.
regards
sandie

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