Hi,

We've recently discovered an aggressive pest on our Olive Tree which we're struggling to identify to remove and possibily identify. All the discussions we've had so far result suggestions that it may be Red Spider Mite however I'm wondering if it's something else.

They're small (1 to 2mm) and vary in colour from light red to black which are possibly mature or well fed examples. They tend to cluster round cracks on the bark or a branch joints and eat into the tree forming circular holes where you'll find clutches of them. I've attached some pictures (sorry they're not so clear however they might help to identify them).

I've tried spraying the tree twice with pesticide and this significantly reduces their number each time however the survivors breed very quickly and soon repopulate the tree in a couple of weeks.

Any advice on what these are (links to pictures wouild be handy) as well as effective treatment methods would be really appreciated.

Many thanks,

Mark

Attached Images

	pest1.JPG (39.1 KB, 11 views)
	pest2.JPG (45.0 KB, 9 views)

Mark,

If you are Australian may I suggest that Professor Robert Spooner-Hart from University of Western Sydney would be a good start point. Alternatively the IOC book, Olive Pest and Disease Management will offer advice with pictures. You can get a copy from the AOA, secretariat@australianolives.com.au

Yours,
Dan

Thanks for the advice Dan. I'm in the UK however I think I'll try and get a copy of the book as I'm sure it'll come in handy.

While I'm not keen on using pesticide I'm going to try blasting weekly for a month or so, since I've read that eggs are not usually killed by pesticide so I'm hoping that regulary spraying will catch any hatchlings that missed the last spray.

Fingers crossed!

Hello Mark,

By your description i think you're right, you have a mite infestation.

Mites thrive on hot dry conditions, which probably your case, also an uncontrolled increase in population would indicate the absence of predatory mite.

I imagine by your description that you have only one olive tree, probably in a garden?
If this is the case I would recommend you avoiding any dangerous pesticides, you can use summer oil (Horticultural oil - Wikipedia, the free encyclopedia) to control the mite population, applying it particularly in the areas where the mite concentrates. But pay attention these treatments also will kill the predatory mite, so in a few weeks/mouths the mite population will build up again.

You can also try and introduce some predatory mite in your olive tree, like is described here: Achieving Biological Control of European Red Mite in Northeast Apples

Hope I've helped.

Cheers,

__________________
João Correia
Cascais - Portugal
____________________________________________
msn: jorgegranja@yahoo.co.uk

skype: JoaoJCorreia

Thank João. Yes, we've only 1 olive tree in our garden and this was purchased recently so I'm guessing we don't have any predatory mights controlling the population.

I've found a company that supplies them so I'll give that a try instead as I'd prefer a natural solution to this problem.

Thanks again,

Mark