Magnolia scale is a sucking insect or sap feeder that feeds off the Magnolia and excretes “honeydew” which attracts flies, aphids, ants and creates black sooty mold. Life cycle is one generation per year. They overwinter as nymphs, mature in June ( that is when you can recognize them ), lay eggs, which hatch in late August. 

First control to use is Bonide Tree and Shrub Insect Control ( Imidacloprid) in early May.  Follow directions of amount to use according to the size of tree. Mix with water and pour around the base of the tree. The chemical will work its way into the system of the tree, which the scale will then suck in. Imidacloprid last for a year, apply again the next year. 

Late August and the again 10 to 14 days later you will spray for the crawlers which have hatched and are most vulnerable. These will be the larger scale next year, and if not killed now can engulf branches as they grow next year.  

If scale is limited to a few branches, prune them off or wipe off. 

Spray with: 

Bonide Eight (permethrin) or (lambda-cyhalothrin), Insecticidal Soap, or Malathion,  

You can always spray periodically through summer for control of aphids and flies also. 

Late Fall and early Spring you can spray with All Seasons Dormant Oil or Neem Oil to suffocate any remaining scale. 

Scale thrives on stressed plants. Keep them fertilized and healthy by amending the soil with compost or organic fertilizers and pruning after flowering. 

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