Giant pine scale
Giant pine scale (Marchalina hellenica) is a tiny scale insect that lives by sucking the sap of pine, fir and spruce trees. Adults grow up to 12 millimetres in length (Figure 1). Each female produces over 300 eggs (Figure 2) between November and January, which then hatch into crawlers.
Giant pine scale infested trees have white cotton wool-like wax on their trunks and branches (Figure 3). While the insect typically prefers the lower part of the tree - the trunk (Figure 4), it can also be found on branches and exposed roots.
Giant pine scale in Victoria
Giant pine scale was confirmed in Melbourne's south-eastern suburbs for the first time in 2014. Infested trees are present in various suburbs of south-eastern Melbourne and Tyabb as shown in the map below.
Check if you're in an area known to have giant pine scale
Use the interactive map of Victoria to find out if you have found giant pine scale in a new location:
- Enter your full street address in the box below and then click the 'Am I Affected?' button.
- If your address is displayed within a red area – the south-eastern suburbs of Melbourne and Tyabb, you are in the infested area.
- If your address is displayed within a green area – the rest of the state, you are in a non-infested area.
Potential impact of giant pine scale
Giant pine scale live in large numbers and can affect the health and safety of the trees they live on. Heavily infested trees can dry up and die from the insects feeding on the tree's sap. If not properly managed, they can impact our:
- softwood plantations
- residential properties.
How giant pine scale spreads
Giant pine scale spreads by crawling to nearby host trees.
People can also unintentionally spread it when they:
- move infested plant material (for example, branches, mulch and logs)
- use contaminated gardening equipment
- carry it on clothing, machinery and cars.
So, it's important to take precautions to avoid spreading the pest to other trees.
- Pinus halepensis (Aleppo pine)
- Pinus radiata (Monterey pine)
- Pinus pinea (stone pine).
Overseas, giant pine scale has also been found on the following species:
- pines (Pinus brutia, P. sylvestris, P. kochiana, P. laricio tauricus, P. nigra salzmannii, P. sosnowskyi)
- firs (Abies cephalonica, nordmenniana)
- spruces (Picea engelmanni, P. orientalis).
Trees that can look similar to pines, spruces and firs but are not hosts of giant pine scale include cypresses and Araucaria, Allocasuarina, Casuarina and Callitris species.
Managing giant pine scale
There's a new insect being found in Melbourne's south-east called giant pine scale. Giant pine scale is a tiny scale insect that feeds on the sap of pine, fir, and spruce trees. Between November and January, each female produces over 300 eggs, which hatch into crawlers between late November to May. Giant pine scale infested trees have white cotton wool-like wax on their trunks and branches. Adults typically prefer the trunk, however it can also be found on branches. They continue to grow up to 12 millimetres, and around September, they produce eggs within their bodies and eventually die.
The problem with giant pine scale, is that they eventually kill trees they live on. Heavily infested trees can dry up and die from the insects drinking the tree's sap, impacting parks, forests, plantations and homes and the aesthetic value of neighbourhoods if not managed.
Giant pine scale spreads by crawling between host trees and by people moving infested plant material, gardening equipment, and machinery. Take care to avoid spreading the pest if it's on your property or one you're working on. Consider cutting down the entire tree. Dispose of infested tree material via your green rubbish bin or by leaving them on your property if there is enough land. Clean all plant material off used gardening equipment using a solution of 80% methylated spirits and 20% water and paper towel.
For advice on managing trees on your property, speak to an arborist or tree specialist. Arborists or tree specialists who work with host or infested trees should practice good hygiene to avoid spreading giant pine scale to other properties. Check and decontaminate your clothing, machinery and tools for signs of pest, soil or plant material before leaving the property.
When transporting infested material for disposal, remember to fully cover up your load, so that infested plant materials don't fall of during transit. If you find giant pine scale on a pine, spruce or fir tree outside of Melbourne's south-east, report it to Agriculture Victoria. Avoid collecting samples from infested trees, as this can spread the insect further.
For more information on managing giant pine scale, visit www.vic.gov.au/giantpinescale.
The following gardening and equipment hygiene tips will assist residents, landholders, gardeners and contractors in managing giant pine scale infested trees to avoid further spread.
Residents and landholders
If you have giant pine scale on your property, there are a range of things you can do to help minimise its spread:
- Where possible, keep fallen or cut tree branches on your property.
- Cut any infested branches that hang over the house or any structures (for example, shed, tanks, swings and fences).
- Dispose of unwanted tree branches, needles and pinecones using your green waste or local council transfer station (remember to bag or cover your waste during transport).
- Clean all plant material off gardening equipment using an 80% methylated spirits to 20% water solution and a brush or paper towel.
- If you decide to have the tree removed, hire an arborist who has been trained in handling giant pine scale infested trees.
Contractors working with infested trees
When working on infested trees, it's important to practise good plant and equipment hygiene to avoid spreading giant pine scale to other properties:
- When entering a site, take a hygiene kit with you that includes paper towels, 80% methylated spirits to 20% water solution, a bristle brush, disinfectant wipes, plastic bags and spare clothes.
- Check the site for any pests or diseases.
- Clean and decontaminate equipment between trees using the methylated spirit solution or disinfectant wipes.
- Clean and decontaminate your machinery, tools and clothing (or change into spare clothing) before leaving the site.
- When transporting infested material for disposal, remember to fully cover your load so insects don't escape during transit and to dispose of material to avoid further spread.
Download the fact sheet:
- Managing giant pine scale on your trees (PDF - 933.2 KB)
- Managing giant pine scale on your trees (WORD - 17.1 KB)
Take the Giant pine scale eLearning course. Note this course is hosted on the Agriculture Victoria Learning Management System. Please register and choose this course from the Goals Catalogue.
Figure 1 – 4, Agriculture Victoria, Department of Jobs, Precincts and Regions.