These spider mites damage magnolia trees by removing plant juices through feeding, leading to.

To control magnolia scale, remove and destroy heavily-infested branches.

Treat with a contact insecticide (horticultural oil, insecticidal soap, other synthetic insecticide) or a systemic insecticide (imidacloprid) in late August or early September. Dormant horticultural oil. Apr 17, To control magnolia scale, remove and destroy heavily-infested branches. Treat with a contact insecticide (horticultural oil, insecticidal soap, other synthetic insecticide) or a systemic insecticide (imidacloprid) in late August or early September.

Sep 21, Calico scales (Eulecanium cerasorum) are bugs that kill magnolia trees. These pests have black and white markings (that turn dark brown with age) and measure 6 to 8 mm in diameter.

Magnolia may be subject to leaf spots caused by the bacterium Pseudomonas syringae or a large number of fungi. Leaf spots rarely require chemical controls. Rake up and dispose of infected leaves. Canker diseases will kill branches. Cankers on branches can be pruned out. Keep trees healthy with regular fertilization and by watering in dry weather. Furthermore, a healthy magnolia can generally withstand scale infestation without serious damage.

If the scales are limited to only a few branches, prune the infested stems off the magnolia tree.

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Jul 11, It turns your tree into a nuisance and even a danger, especially if you or your children are allergic to stings. While an arborist can help you handle the source of the problem, the magnolia scale producing the honeydew, their treatments, including horticultural oil, take time to be effective.