The Star Magnolia is well-know for being disease- and pest-resistant. My two specimens have thrived for 14 years but recently developed a problem. They are planted 25 feet apart in an established bed, separated by holly and periwinkle ground cover. A copper bird bath was placed between them about 3 years ago. Both Magnolias are covered in galls that are exclusively on the tips of this years growth. The nodular growths are green with brown speckles (photo attached). I would appreciate any information on this disease.
It's the fruit, not a disease. There's a seed in each of those swollen 'knobs'; when they are ripe in 2-3 months, they will split open to reveal the bright orange seeds.
If you look at them you can see they are in the same positions flowers were, have the same stalks the flowers did.
I was looking for information on the same topic and found your question and comments. They are surely galls on the developing Magnolia stellata fruits. I cut some open and there is a larva in each. This is the first year I have had a problem, 2013. I know this is an old thread but I thought it might be worth asking if anyone has any information. I'm from the northeastern US zone 5
