Hi there. I noticed some small 0.5cm white growths on my tree stems/branches (but not on the leaves). They seem to have spread quickly to other parts of the garden. I've included a photo as well, if it helps. We're in Sydney, Australia. can anyone identify what it could be, or how to treat it? Thanks very much. John.
There is a group of insects called Scale. They come in many shapes and colors. I suspect this is what you have on this plant.
Thanks very much for the info! I think you're right about them being Scales. They're spreading very quickly. I'm wondering how I can get rid of them? At the garden store, they sell products for Scale made of either "low toxic Pyrethrum and White Oil" or "Petroleum Oil/White Oil". Which is best? Thanks for your help with this
Scale insects follow similar life cycles:
Adults are anchored to the plant, and covered with a waxy covering that is almost impenetrable by pesticides.
Young are called 'crawlers'. They crawl out from under the mother and migrate to a new location. Some stay on the same plant, others can move to another plant. I am not sure how. Do they crawl? (seems unlikely- that is a LONG way to crawl for such tiny bugs) Are the transported by birds? (could well be)
The young are vulnerable to pesticides, so timing the spray is almost more important than which one you use. A spreader-sticker can help a lot.
You can try to smother the adults with horticultural oil. I think I would try the pyrethrum & oil combo.
Read all the precautions about timing the spray to not burn the plant- certain plants are more sensitive to oils, especially if the weather is warm.
Thanks very much for the tips. I've tried a home-made mix of soap & vegetable oil, and also a bit of white oil (the only thing the store had in stock over the weekend), and it seems to be working!
It will take time, and monitor the pests through the year, and figure out when the crawlers show up. You might need a hand lens to see them. This is the best phase of their life to control them.
