Management of Olive Lace Bug and Black Scale

03 Mar Management of Olive Lace Bug and Black Scale

Posted at 12:40h in OliveCare by

MANAGEMENT OF OLIVE LACE BUG: (Froggattia olivinia)

Olive Lace Bug: https://olivebiz.com.au/wp-content/uploads/2020/08/OLIVE-LACE-BUG.pdf

OLB Management: If required, lace bug can be targeted by judicious use of insecticides.  Several, including pyrethrum and potassium soap may be organically acceptable inputs.  Sprays need to be targeted at young nymphal stages, so monitoring for nymphal hatch of especially the first generation in spring is important.  Opening up tree canopies exposes nymphs to greater likelihood of dehydration, and also to access by sprays targeted against them.  Stressed trees are more susceptible to lace bug attack, so maintaining healthy trees assists in management of this pest.

Current approved chemical control options for olive lace bug:

  • New PER 89943 Trivor Insecticide (acetamiprid + pyriproxyfen) Permit to 31 January 2024, Group 4A (Neonicotinoid) and Group 7C (Insect Growth Regulator) APVMA Permit listing TBA

Maximum of 2 applications per season. Withholding Period 28 days

Apply one spray only at the nymphal stage. Withholding Period: 56 days

Maximum of 4 applications per season. Withholding Period: 42 days.

Maximum of 4 applications per season. Withholding Period: 14 days. Demonstrated efficacy but disruptive to beneficials.

Maximum of 2 consecutive sprays. Withholding Period: 1 day – trial work currently underway for label registration.

Other “soft” control options for OLB:

Note: Many growers report that Natrasoap® and its equivalent – potassium salts mixed with oil products to be ineffective.

  • Potassium carbonate and potassium bi-carbonate are foliar nutrients that may have incidental contact agent pest control properties.
  • Horticultural spray oils are simple, easy to use safely, and are kinder to beneficial insects, but they do depend on the spray fully “wetting” the instars and insects. Since the instars and insects live on the underside of olive leaves, the spray equipment must be set up carefully to saturate the undersides of the leaves right across the tree. http://websvr.infopest.com.au/LabelRouter?LabelType=L&Mode=1&ProductCode=59092

Note: Paraffinic and vegetable oils (including olive oil) – contact agents – potential low toxicity organic options –  however there are implications for use of vegetable oils on EVOO fatty acid profile.

  • The native green lacewing Mallada signata is commercially available. [1]Robert Spooner hart says he “has several times observed in the field lacewing larvae attacking nymphal stages of OLB (including with carcases on their back). But this has been rare, and I have been through many populations of lace bug with no obvious signs of predation, except for occasional spiders”. https://bugsforbugs.com.au/product/lacewing/

Suggested resistance management strategy for the control of olive lace bug (OLB):

(Assuming the Australian olive industry has legal access to the above Group 1B, 3A, 4A, 4D, 7C pesticides)

  • DO NOT apply consecutive sprays of solo products containing Group 4A, consecutive sprays include mixtures containing Group 7C pesticides.
  • Consecutive application includes from the end of one season to the start of the following season.
  • DO NOT apply consecutive sprays of solo products containing Group 1B, Group 3A, Group 4D pesticides.
  • Rotate use of products from Group 1B, Group 3A, Group 4A, Group 4D or Group 7C pesticides.

FURTHER INFORMATION ON OLB CONTROL OPTIONS:

There are some excellent resources available including the outputs by Dr Robert Spooner-Hart and Len Tesoriero from  “An integrated pest and disease management extension program for the olive industry (Project OL17001)

https://olivebiz.com.au/ipdm-project-outputs/

Management Options for Olive Lace Bug

Dr Robert Spooner-Hart

Olive Lace Bug in Western Australia:

Stuart Learmonth

Management of Olive Lace Bug

Dr Vera Sergeeva (Olive Lace Bug):

MANAGEMENT OF BLACK SCALE (Saissetia oleae) in Olives

Black Scale in Olives: https://olivebiz.com.au/wp-content/uploads/2020/08/BLACK-SCALE.pdf

Black Scale Management: If required, black scale can be targeted by judicious use of spray oils or insect growth regulators. Sprays need to be targeted at crawlers and young nymphal stages, so timing is critical for effective management. This makes monitoring for crawler development important. Opening up tree canopies exposes crawlers to greater likelihood of dehydration, and also to access by sprays targeted against them. Management of black scale will reduce ant problems, and vice-versa

Current approved chemical control options for black scale:

  • New PER 89943 Trivor Insecticide (acetamiprid + pyriproxyfen) Permit to 31 January 2024, Group 4A (Neonicotinoid) and Group 7C (Insect Growth Regulator) Maximum of 2 applications per season. Withholding Period 28 days

APVMA Permit listing TBA

  • Registered fenoxycarb (Insegar): Group 7B insect growth regulator, Maximum of 2 applications per season. Withholding Period 56 days

Label: https://www.syngenta.com.au/product/crop-protection/insegar-wg

  • Registered pyriproxfen (Admiral), Group 7C Insecticide, Maximum of 2 applications per season. Withholding Period: 7 days

Label: https://sumitomo-chem.com.au/sites/default/files/sds-label/admiral_adv_label_0.pdf

  • Control of Use: Vic Only: Bayer Confidor 200 SC Insecticide, Group 4A Insecticide (neonicotinoid)

Label: https://www.crop.bayer.com.au/find-crop-solutions/by-product/insecticides/confidor-200-sc-insecticide

Organic and other “soft” Control Options for Black Scale:

  • Black scale has been the subject of biological control projects in the Australian citrus industry since 1902. From 1902 to 1947, 24 species of beneficial insects (22 parasites, two predators) were released for its control. These included Metaphycus anneckei in 1902 from South Africa and helvolus 1943–47 from the USA. From 1998 to 2003, M. helvolus and M. lounsburyi were released in citrus as part of a Horticulture Australia Ltd-funded project.
  • Surveys as part of a Rural Industries Research and Development Corporation project in WA showed that the egg predator, Scutellista caerulea, is most common. helvolus and M. anneckei are poorly established. The effectiveness of S. caerulea is limited, because populations build up too late to prevent scale outbreaks. Establishment of M. helvolus and M. lounsburyi in olives is recommended. However, there may be problems in obtaining insects commercially for release.
  • General predators such as lacewings and ladybirds also feed on black scale.
  • Ant control is required where growers are interested in pursuing biological control, as ants harvest honey dew from black scale, and protect the scale from parasites and predators.
  • Potassium carbonate and potassium bi-carbonate are foliar nutrients that may have incidental contact agent pest control properties
  • Paraffinic and vegetable oils (including olive oil) – contact agents – potential low toxicity organic options – however there are implications for use of vegetable oils on EVOO fatty acid profile.

Note: Horticultural spray oils are simple, easy to use safely, and are kinder to beneficial insects, but they do depend on the spray fully “wetting” the instars and insects. Since the instars and insects live on the underside of olive leaves, the spray equipment must be set up carefully to saturate the undersides of the leaves right across the tree.

Black Scale References:

Sonya Broughton and Stewart Learmonth – Management of Black Scale and Apple Weevil in Olives: RIRDC 12/019): and updated review (December 2019)

There are some excellent resources available including outputs by Dr Robert Spooner-Hart and Len Tesoriero from  “An integrated pest and disease management extension program for the olive industry (Project OL17001): https://olivebiz.com.au/ipdm-project-outputs/

AOA Fact Sheet: Managing Black Scale in Olives

 

[1] Robert Spooner-Hart personal communication