bay laurel sucker

Plants affected

• bay laurel

Easily confused with

• bay leaf scorch

  How to tell them apart: Both attack bay laurel (Laurus nobilis) leaf margins, but Stigmina deflectans is a fungus and Trioza alacris (bay sucker psyllid) is an insect. Stigmina produces flat, dead, dry brown-to-purplish necrotic blotches and scorched edges or tip burn; the tissue is sunken and lifeless, the leaf stays flat, and tiny dark fungal dots may show in the lesions, worse in humid shade. Trioza causes the living leaf margin to thicken and curl/roll downward into a swollen yellow-then-brown gall-like fold, and inside that curl you find soft pale-green nymphs coated in fluffy white wax, plus sticky honeydew and sooty mould on leaves below. Rule of thumb: flat dead lesions with no insects = Stigmina; thickened curled edges with white wax, honeydew and live nymphs = Trioza.

Common questions

Do I have to report bay laurel sucker?

No. bay laurel sucker is not a notifiable organism, so there is nothing to report to an authority. Treat it as a normal garden problem.

How is bay laurel sucker treated?

Mainly with biological and cultural measures — removing affected material, changing the conditions that favour it, and treating with agents approved in your country. The exact steps and their timing depend on the plant, the season and where you live: Dr. Phyto works them out in a free diagnosis.