Phytotoxicity on Poinsettia, California, 1978

Tests were conducted at the Paul Ecke Poinsettia Ranch, Encinitas, from Sept 7-Dec 10. The following materials and rates were evaluated: Resmethrin 2E (SPB 1392), Fenvalerate 2.4E (SD-43775), Permethrin 2E (SPB-1513) (all at 0.1 lb ai/100 gal) and Oxyamyl 2E (Vydate) (0.5 lb ai/100 gal). A spreader-sticker, X-77, was added at 1 ml/gal of finished spray. Materials were applied until runoff to both sides of bracts and leaves using a 10 gal hydro-piston pump delivering 2.5 gpm (9.5 litres per min) at 100 psi. There were 3 replicates/variety/treatment with 4 five-inch pots/replicate. Applications were made on 3 dates: 1) when plants were well rooted (ca 3-4 weeks after sticking), 2)when bracts began to show color and flower buds were evident and 3) when 0.5 - 0.75 in bloom. A commercial application of Aldicarb 10G (Temik) at 0.0416 g ai/ft was applied on Oct 20. Observations of phytotoxicity were made 2,4 and 7 days after each spray application and compared to an untreated control.