Lemon tree disease - white fluff?

[joidevie]

I was wondering if anyone if anyone could help with identifying the disease on my small lemon tree..

Along many of the branches is a white "cotton wool" type deposit, a little stick in bits, but essentially dry..

I chatted with a local gardener who pointed me towards a fairly powerful insecticide which is not easily available called something like cochin**** or something?? Does anyone have any ideas as to what I could be thinking of?

Many thanks for any ideas..

[ventodue]

Sounds like wooly aphid (there are several different species).  These are small insects which feed on the tree's sap and, for protection, cover themselves with a white fibrous material that looks like cotton wool.

They don't do an enormous amount of damage to the tree, but to get rid of them, there's no need to resort to chemical warfare.  Try hosing them off first, using a mixture of washing-up liquid and water applied with a hand sprayer.  Otherwise, tap 'wooly aphid' into your favourite search engine and you'll find some other suggestions.

The word your friendly gardener was using was "cochenille", a generic term for any form of sap-sucking insect.

P.s  In English, 'Cochineal' is normally used as the common name for a particular species of scale insect, Dactylopius coccus, from which a red dye can be made.  It is native to Central/North America and feeds on Opuntia cactus.

There is a similar insect in France which can also be used to make a red dye.  It's scientific name is Kermes vermilio and it lives on Kermes Oak, Quercus coccifera, which grows around the Mediterannean basin.  

HTH

Craig

[joidevie]

Great.. Couldn't have asked for a clearer and for informative answer! Many thanks.. Fairy to the rescue..