Hi,
I found this on the underside of quite a few leaves on my Lemon Tree. I does not seem to be on all leaves. Also, in parts the leaf that are infected seem to be turning black. The upper side of the leaf however, looks quite normal.
Any idea what is the problem, and how can I fix it?
I live in Cyprus.
Many thanks in advance.
DAVID CRISP
Read more: http://davesgarden.com/community/forums/t/1377951/#ixzz3F5OpKEsQ
http://www.ipm.ucdavis.edu/PMG/C107/m107apyoungtrees.html
This is a link that might help. It is at the UC Davis (California) web site.
UC Davis is one of the biggies in agriculture. I am not sure how much of the pest info is the same, though. Pests in Cyprus may be different than many of them here.
Still, it is a start. I looked through it and suggest you scroll down to Asian Psyllid, and the next box down which is a sort of general box about sucking insects like aphids (MANY species) and their relatives.
Many insects produce a sort of waxy protection where they are feeding. Can you scrape through some of that white stuff and see if there are bugs of some sort under it?
Is the actual tissue of the leaf turning black? Or is it a sort of black coating that is growing on the leaf, but can be rubbed off?
I suggest you have an infestation of green fly or a mix of white fly also, the white stuff is the empty egg casings and the tiny green lump are the adult green flies I think, the pictures are not too clear.
you can use a cotton wool ball (ladies make-up removal pad) dip the cotton balls into warm soapy water and wash off the white stuff, also use a clean ball of the cotton every time, you don't want to spread the white stuff onto areas where there is none.
You need to wash the black stuff off too, I think this might be what we call here in UK the honey dew (excrement from the flies) IF you don't remove the stuff, ants will become a pest as they start to farm the small flies as the ants love this sweat honey due.
I would be misting your plants foliage to help keep control of those small sap eating flies, I use a mixture of water and a few drops of dish soap washing up liquid, this helps kill the flies as soon as they hatch.
Make sure you mist the under side of the foliage as that's where the flies forage and hide from any of their enemies like lady birds etc that thrive on the eggs AND the flies.
If you use a spy glass to look at your underside foliage, you will then see the tiny flies move about, PLEASE don't panic, these little flies live of greenery, they don't like human contact and in future, IF you spot the start of an outbreak, you can just crush them between finger and thumb, take a wet cotton ball and wipe the leaf clean again.
There are chemical spray's you can use but personally I would rather leave stuff like that till it was a last resort, IF you persist using the dish soap mix with water, you will have a safe removal of this pest, also I would mention that Lemons are a food plant and I would never use chemicals on any edible plants either the foliage OR the fruit, just also remember IF chemicals are used at the time of flower formation, there's every possibility the chemicals could end up within the fruit..
Hope this helps you out a little.
Kindest Regards.
WeeNel.
