The pine needle scale can be tricky to spot. Small, white spots are the giveaway.
Uh-oh, white spots
If it’s fall or early spring where I live, it’s always what I think it is – pine needle scale. Here’s why they can be tricky to spot. When they grow on the inside surface of a pair of pine needles, they’re all but invisible.
A sliver of white is the giveaway
Peeling the needles apart reveals the insect – small white spot with even smaller yellow dot at one end.
Pine needle scale
If I’ve spotted them early enough, I’ll find singles or pairs of them on a limited number of needles. If I do nothing about it, a few days later I might find far more.
Yuck – more pine needle scales!
The reason I’m not a fan – they can be hard to control. Many of the weaker pesticides have trouble killing scale. I usually start with light-touch approaches and mount increasingly potent assaults as need be. My general approach is the same as it is for any scale:
- If there are only a few I’ll scrape them off with my fingernail
- If I have to spray, I’ll start with oils
- If oils don’t get them under control, I’ll using something more toxic, though I typically avoid this last step as I don’t like using pesticides.
What’s the most important thing to know about treating scale? If at all possible, avoid getting it in the first place. How might one go about reducing the potency and number of infestations?
- Keep your trees healthy. This includes lots of sunshine, appropriate water and fertilizer and well-draining soil.
- Don’t give them space to hide. Leaving old leaves or needles in place prevents light and air from reaching the tree’s interior – that’s how scale like it.
- Use oils on a regular basis. Oil sprays are the least toxic treatment for scale.
- If you know there are lots of scale in the area or have fought infestations in the past, systemic pesticides are a good bet.
Uncontrolled scale infestations can greatly weaken and even kill bonsai. Be on the lookout for them!
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