Formula:

Iron sulphate ...............40 lb.

Sulphuric acid ............ ... 2 „

Warm water ...............10 gal.

Dissolve crystals of iron sulphate in the water in a wooden vessel, and add the sulphuric acid, and apply hot and fresh in winter to fruit trees. If allowed to stand for more than twenty-four hours the salt recrystallizes, and the solution is then less effectual.