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8 messages
06/10/2013 at 11:36

Have a large pine tree which is rapidly being sucked dry by an aggressive infestation. What insecticide should I use and how can I ensure my other pine/conifers are not infested? Many thanks.

06/10/2013 at 11:48

HI Chris

You're in Lincs; pine beetles are native to the Americas.  

What symptoms are your trees showing?  Photos of trees and any insects found would be good 

06/10/2013 at 11:59

Hi there, these small black beetles are sucking the sap out of the branches and are moving to the trunk. The only thing I found online that matches was the pine/turp beetle. They've infested the lower part of the branches and seem to dislike sunlight. Some beetles seem to have a tiny white stripe running horizontally on it's rear.They have thread like protrusions that they bore into the bark. In size they're about the size of a grain of rice. Thanks.

06/10/2013 at 12:02

Oh and symptoms are the tree is weeping sap where it's being attacked which wasps are lapping up and some needles are starting to discolour and go yellow. I've been squashing them by hand and blow lamped a few hundred, carefully haha.

06/10/2013 at 12:23

I think they're probably aphids rather than beetles - they will be producing honeydew which is what the wasps are after.  Are there any ants about?  They're usually after the honeydew too.

What sort of trees are being attacked - can we have a photo?

06/10/2013 at 12:26

Yes you're right, it's cinara piceae aphid down to the white stripe. Only I used a rose aphid spray to no effect but I have hdthe spray for many years. What would you recommend please? I tink this tree is a goner, but I need to protect the others. Will the frost kill them off, larvae as well?

06/10/2013 at 12:38

I really don't know - I imagine the winter will kill a lot of them off but they obviously survive somehow.  

I'd dry squirting as many off as I could with a hosepipe.  

I think received wisdom is that healthy trees don't get too badly damaged by aphids, so I'd make sure the other trees don't get stressed - has the affected one suffered in the dry summer we've had this year?

06/10/2013 at 12:46

I think the only sure answer is reluctantly, insecticide. Even the ones that escaped the blow lamp crawl back on, it's unbelieveable how quick they've spread, I thought it was a fungus at first. It's a very well established tree and was kept watered, but I did notice a patch of the honeydew you mentioned prior to trimming a large branch which must have attracted more.

Many thanks for your help.

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