Isoxaben + Dithiopyr Crop Safety – 2021

Liriope clump of grasslike foliage

Research Summary Abstract

Fortress (isoxaben + dithiopyr) was registered in 2018 for environmental horticulture crop uses. Between 2018 and 2020, IR-4 examined 17 crop species / genera to expand this label to other crops. Of these, 2 crop species (Hydrangea macrophylla and H. paniculata) exhibited no or transient injury. Eight crops exhibited significant injury in this research: Digitalis grandiflora and D. purpurea.

Link to Summary: Isoxaben + Dithiopyr Crop Safety Summary