Some common fungicides used to treat sick plants

Sunset  – September 7, 2004

The fungicides below are listed alphabetically by common name (the name given on the label under “active ingredients”). If the trade name differs from the common name, it is given in parentheses.

Chlorothalonil dissipates over time. The remaining products listed are systemic: applied to a plant, they are absorbed by the foliage or roots to prevent or cure infection from within. Systemic fungicides must never be used on food crops.

When using any fungicide, read the instructions carefully and follow them exactly. The products listed here require that you wear protective clothing, goggles, and a breathing mask for application.

Chlorothalonil (Daconil) Multipurpose fungicide for prevention of diseases of lawns, fruits, vegetables, and ornamentals.

Thiophanate-methyl Systemic. Effective against many plant diseases, including powdery mildew and black spot.

Triadimefon (Bayleton) Systemic. Used for prevention or eradication of powdery mildew, rust, and some lawn diseases.

Triforine (Funginex) Systemic. Used for prevention and eradication of powdery mildew, rust, black spot, and a variety of other diseases.