wrote in message
Yes, I agree with Nick, common problem with all citrus, shame you cut the
tree back as they can be removed with a fingernail (messy) or blasted off
with a sprayer full of water with a drip of washing up liquid. Go over
the
whole plant leaf by leaf and stem by stem making sure you get the tiny
ones
in the cracks. Takes time and you will get wet too.
After a couple of weeks repeat the procedure and inspect your plants
closely
in future for this nasty pest which is persistent.
The stickiness is their waste product. :-)

Thanks for your help. I'm sure I tried washing up liquid before, but I
guess I did not persevere enough. Now that I know what they are I did
a search on "scale insects" and have seen pictures and that is exactly
what they are. I also read that you can buy ladybirds and wasps that
live off them. The wasps need a warm temperature, so I cannot use them
yet, but I am wondering about buying the ladybirds.

It's the high pressure blast from the sprayer that does the job which is why
you must keep pumping it up to full pressure while doing the cleaning. The
washing up liquid just helps a bit and also removes that sticky stuff at the
same time.

Don't bother with biological control for one plant, it's much too expensive
and probably won't work too well.
--
Regards
Bob

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