AusBonsai

My poor citrus can't catch a break. It got scale, got eaten by the possum, sprayed with scat to keep possum away which burned all the leaves, now it has scale again. Also something is still eating it.

The scale wasn't on the leaves, but all over the lower trunk. Tiny white ones. I have gotten my white oil and a toothbrush and scrubbed it all off.

There wasn't any on the leaves though - I thought they could only harm the tree in their bigger form, or can enough of the smaller ones hurt the tree if they're down on the trunk?

Sounds like mealy bug mate, but not 100% sure without seeing it. They don't seem to affect my bonsai's too much, but I'm sure they will over time.

Keep an eye out for ants, as they will spread the mealy bug around the tree and make matters worse.

I just use confidor to get rid of them, but white oil works too but isn't realy a permanent solution

It's had 2 lots of confidor now and it did have a big ant problem but not anymore. Not thriving at all. I thought mealy bug and scale were the same thing?

Beano wrote:It's had 2 lots of confidor now and it did have a big ant problem but not anymore. Not thriving at all. I thought mealy bug and scale were the same thing?

Don't quote me on this, but I believe 'scale' is a broad term for scale insects

The ants harvest the honeydew that is a waste product of the mealy bug, which is why ants love them. They won't kill them though, they spread them and harvest them like we do milk from a cow. Ants can also build a little nest in/on the tree to proctect the mealy bug, which has happened really badly to a grevillia at my place. Looks like it has really badly swollen joints or something

Because the ants harvest them though, its hard to get rid of them completely. They may be spreading from another tree or something like that

* this is all just from what I've learnt from dealing with them over the last year, someone may well be able to correct me if my info is off

Mealy bug and scale are quite distinct. Scale insects make a hard shield shaped shell to live under. Mealy bugs are soft and have white fluff to protect themselves from predators and sun. They look like little bits of cotton wool. Mealy bugs also liv under the soil on the roots which is why they come back so quickly. Oils and contact insecticides only kill the ones above ground but a systemic will kill even hidden ones.

Ants will farm both scale and mealy bugs for the sweet secretions.

If your problem keeps returning there are probably some living on plants nearby that can get onto your plants.

shibui wrote:Mealy bug and scale are quite distinct. Scale insects make a hard shield shaped shell to live under. Mealy bugs are soft and have white fluff to protect themselves from predators and sun. They look like little bits of cotton wool. Mealy bugs also liv under the soil on the roots which is why they come back so quickly. Oils and contact insecticides only kill the ones above ground but a systemic will kill even hidden ones.

Ants will farm both scale and mealy bugs for the sweet secretions.

If your problem keeps returning there are probably some living on plants nearby that can get onto your plants.

Thankyou for the clarification Shibui

I see! They are mealy bugs then, little white fuzzy things. Thanks for the help! I think they could be coming from underground because they were small ones concentrated on the trunk around the bottom.

Sorry I didn't take a photo before I scrubbed them off.

This is what they looked like - I got this off the Yates website, apparently it's the white louse scale. I definitely had this on the trunk, and I haven't seen the mealy bug creatures for months. Is this picture of scale or mealy bug?

The mealy bugs I have seen are much fluffier than those so i would go along with Yates diagnosis. Fortunately don't think I have not seen white louse scale down here.