What are Pine Sawfly?
Pine sawfly are a small brown coloured, winged insects that measure approximately 7mm to 10mm. There are two main species of pine sawfly, pine sawfly (Diprion pini) and fox-coloured sawfly (Neodiprion Sertifer)
It is however the caterpillar like larvae that do most of the damage and can strip a bonsai pine tree in a matter of days. They measure approximately 25mm long and have differing colour characteristics.
- Pine sawfly (Diprion Pini) are a pale green in colour with a brown head and black markings.
- Fox-coloured sawfly (Neodiprion Sertifer) are a brown / green colour with a black lateral stripe and a black head.
What Trees do they infest?
As the name suggests, they infest pine (pinus) trees of any variety.
The larvae stage will feed upon the needles and strip a bonsai tree in a short space of time.
How to Spot them
- It is best to spot pine sawfly early, in spring and summer look over your pine trees for any caterpillar like insects and compare them to images of pine sawfly
- The caterpillars will arch outwards and the slightest movement of the tree and are usually clustered in a small area
- It is possible for isolated pine sawfly caterpillars too
Non Pesticide Control
- The best approach is to remove the pine sawfly caterpillars by hand, or tweezers, ensuring that you get them all
- We place them on a bird feeding table for wild birds to feast upon
- For persistent infestations you can use a chemical based insecticide such as Provanto Ultimate Bug Killer or Bug Clear Ultra.
- The best chemical treatment is Bug Clear Ultra Vine Weevil Killer which is a systemic pesticide containing neonicotinoid insecticide acetamiprid. This is applied to the soil as a dilute during late summer or early autumn.