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Scale gone mad on my Lilli Pillis Traditional remedies not workin

11 years ago

I have an absolute infestation of white scale on my lilli pilli hedges. I have completely drenched them in white oil and pest oil monthly and even fortnightly and it has done nothing.

My hedges are dying branch by branch and some have been totally dessimated. I've heard that Mavrick and Success may be more useful than the oil. Is this correct?

I'm also wondering about the environment that scale like.I've been told that Lillipilli is quite hardy and I water the lilli pillis twice weekly.Is this providing too good an environment for the scale? Should I turn the water off or will this distress the plants more and make the scale spread further?

Do ants play a role in the spreading of scale? Should I be treating ants simultaneously? There is also some black dust on them is this related to the scale or something else entirely.

When is the best time to treat the scale and stop them spreading?

Any help would be most appreciated as the next step is just to kill them all and start again with something with less problems!

Comments (8)

  • ken_adrian Adrian MI cold Z5
    11 years ago


    welcome to GW ....

    first.. see link

    next.. is your product labeled for monthly use?? and that aside.. the mature ones are impervious to any treatment with their waxy coating.. and you must ID when the babes crawl out and are susceptible to the oil ... and that is once a year .. not monthly ... you are wasting product/money.. if nothing else ...

    third.. ants are usually around.. to 'milk' honeydew from whatever it is ... they are irrelevant to it all ...

    and the black is usually a mold as a result of the honeydew ...

    in other words.. get rid of the scale.. the ants will move on.. and sooner or later the mildew will go away ...

    the real problem.. is that the mature ones.. look no different if they are dead or alive.. just because you kill them.. doesnt mean they are going to disappear ... and frankly.. when it comes to this point.. i usually have a hard time 'looking' at them for years to come ...

    and it is then i think about cutting them down ...

    now i know nothing about this plant.. as i didnt even know it existed before your post ... but if it is like many hedges or flowering shrubs.. there is probably no reason you couldnt cut them to near ground level.. remove EVERYTHING.. treat the stumps for remnants of scale ... and within a few months.. just about have your hedge back .. since there is no insult to the root mass ... and in the meanwhile.. have removed 99.99% of the problem ... [i would burn it.. and find some satisfaction in sending them to the Elysian fields ...funeral pyre and all that ..]...

    hopefully you can find out if rejuvenation pruning' is an option with this plant ..

    good luck


    Here is a link that might be useful: link

  • strobiculate
    11 years ago

    scale can be tricky to contain, but is not as problematic as ken hints.

    in the crawler stage, scale is easy to kill. just about anything other than ionized water will do it (okay, hyperbole, but you get the gist). the problem is, the crawler stage is fleeting.

    however, this is where the dormant oils come in. sprayed about ten days apart, two or three applications take care of a lot of problems. by the way, once the scale is dead, that hard outer shell keeps it attached to the plant stem, so you gotta get your fingers dirty to determine if they are still alive (juicy) or dead (brittle and dry).

    as for specific spray timing and schedule, check with someone local.

    the other option for scale is a systemic insecticide. that outer shell of the scale insect makes it just about impermeable to outside forces. there are some predatory insects that feed on scales, but you gotta know what you have and what feeds on them. and as bad as your problem seems, you are probably going to be spraying something first to knock down the population levels.

    but back to systemics. often applied to the soil, these are insecticides that are absorbed by the plant and distributed through the conductive tissues. again, probably best to talk to someone local to know what works best in particular situations in your area.

  • rhizo_1 (North AL) zone 7
    11 years ago

    That's the worst case of wax scale that I have ever seen. There is no question about what I would do. Off with its head!

  • calliope
    11 years ago

    I have used oils with excellent results on scale infestations. If the plant will tolerate it, then it suffocates all stages of scale. Insects do not become resistant to oil applications.

  • ken_adrian Adrian MI cold Z5
    11 years ago

    motor oil ought to take care of it also ...

    just apply some.. mixed with some petrol


    lol ...

    rhiz ... off with its head??? .. i typed my answer awhile ago ... do you mean you would basically cut it to the ground.. treat whats left.. and watch it explode with growth.. because of no insult to it vast root system??? .. what one might call ... single year rejuvenation?????

    i think i recall the OP is in aussie-land [somehow trying to trick us with that WA next to their name.. for us which is washington] ... and if it is the first true week of winter here .. then they are in the first week of summer..

    is timing an issue???


  • ronalawn82
    11 years ago

    bumperbyrnes, my experience with the cycad aulacaspis scale (Aulacaspis yasumatsui Takagi)
    has taught me that it is a two-pronged attack.

    1. The use of oil/soap solutions against the crawler stage.
    2. The use of a systemic insecticide against the adult stage.
      I used Meritî (a.i. Imidacloprid) as the systemic. I would have preferred Cygonî (a.i. dimethoate) but that chemical was not permitted at the place where I worked. I checked on the adults by crushing them and if I saw a blood colored fluid I concluded that the scales were still alive (but hopefully unwell).
      I sprayed a horticultural - not mineral - oil every five days to smother the crawlers; yet it took me almost six months to bring the infestation down to a manageable level.
      I inspected and treated as a regular routine for another year until I changed jobs. It is an ongoing program.
      I gather that Australia has an Agricultural Extension Service similar to the USA's but I have been unable to find a contact that I could share here.
      It is essential that you make quite sure that the treatments you use conform to the legal guidelines of the Territory in which you live.
  • calliope
    11 years ago

    If oil is applied properly, short of reinfestation from an outside source, it shouldn't take repeated applications. I got rid of a hideous scale infestation over a large ground-cover bed with pruning, discarding and burning the residue and a very good treatment with oil. There is no reason whatsover that oil can't be used on adults effectively. They must respire and oil prevents this. The up side to oil is you don't have to catch them in any particular stage, it's effective against all stages. Systemics are great if it's absolutely necessary but we're drowning the world in iminicloprid and when they become resistant to that, and they are.......what's next?

  • augeydoggy
    11 years ago

    I have a similar problem with pyracantha in Philadelphia. I used a systemic (Bonide) last fall, but they have come roaring back. Because of the thorns and density, it is very difficult to clean the branches. I guess I am looking at systemic plus oil in the spring? Is there a particular systemic for this soft scale?