Clients this week have been finding small weevil-shaped bugs on their magnolias, accompanied by numerous rice shaped holes.
The culprit is the magnolia weevil, also known as the yellow poplar or sassafras weevil. The black, one-eighth inch long beetles are sometimes mistaken for ticks and 'play dead' when handled. They do not bite.
Magnolia weevils over-winter as adults and lay eggs the following spring in newly expanding leaves. After eggs hatch, the larvae mine the leaves producing a brownish, blotchy area. The weevils and damage observed now are from the subsequent (second) adult generation, which chews small crescent-shaped holes in the leaves of magnolia, tulip poplar, and sassafras.
Damage appears most severe on magnolias (southern, sweet bay, etc.) that hold their leaves year-round. The injury does not seriously harm the tree, but the leaf holes are concerning and cosmetically unappealing to some clients.