The preparation of sulfuric acid (oil of vitriol) by the distillation of green vitriol (Iron(II) sulfate) has been known for at least 700 years. Medical use
Plant growth
Iron(II) sulfate is sold as ferrous sulfate, a soil amendment for lowering the pH of a high alkaline soil so that plants can access the soils nutrients.In horticulture it is used for treating iron chlorosis. Although not as rapid-acting as ferric EDTA, its effects are longer-lasting. It can be mixed with compost and dug into the soil to create a store which can last for years. Ferrous sulfate can be used as a lawn conditioner. It can also be used to eliminate silvery thread moss in golf course putting greens. Pigment and craft
Ferrous sulfate can be used to stain concrete and some limestones and sandstones a yellowish rust color.Woodworkers use ferrous sulfate solutions to color maple wood a silvery hue. Green vitriol is also a useful reagent in the identification of mushrooms. Historical uses
Ferrous sulfate was used in the manufacture of inks, most notably iron gall ink, which was used from the middle ages until the end of the 18th century. Chemical tests made on the Lachish letters (c. 588–586 BCE) showed the possible presence of iron. It is thought that oak galls and copperas may have been used in making the ink on those letters. It also finds use in wool dyeing as a mordant. Harewood, a material used in marquetry and parquetry since the 17th century, is also made using ferrous sulfate.
Treatment of the soil or litter to kill intermediate hosts may be beneficial. Insecticides suitable for litter treatment include carbaryl, tetrachlorvinphos (stirofos). However, treatment is usually done only between grow-outs. Extreme care should be taken to ensure that feed and water are not contaminated. Treatment of range soil to kill ova is only partially successful. Changing litter can reduce infections, but treating floors with oil is not very effective. Raising different species or different ages of birds together or in close proximity is a dangerous procedure as regards parasitism. Adult turkeys, which are carriers of gapeworms, can transmit the disease to young chicks or pheasants, although older chickens are almost resistant to infection. Treatment
Flubendazole (Flubenvet) is the only licensed anthelmintic for use in poultry and game birds. Continuous medication of pen-reared birds has been recommended, but is not economical and increases the possibility of drug resistance. Several other compounds have been shown effective against S. trachea under experimental conditions. Methyl 5-benzoyl-2-benzimidazole was 100% efficacious when fed prophylactically to turkey poults. 5-Isopropoxycarbonylamino-2-(4-thizolyl)-benzimidazole was found to be more efficacious than thiabendazole or disophenol. The level of control with three treatments of cambendazole on days 3–4, 6–7, and 16-17 post-infection was 94.9% in chickens and 99.1% in turkeys. Levamisole (Ergamisol), fed at a level of 0.04% for 2 days or 2 g/gal drinking water for 1 day each month, has proven effective in game birds. Fenbendazole (Panacur) at 20 mg/kg for 3–4 days is also effective. Ivermectin injections may be effective in treating resistant strains. Sources

https://web.archive.org/web/20100703145151/http://cal.vet.upenn.edu/projects/merial/Strongls/strong_4.htm
https://web.archive.org/web/20110717194656/http://www.vetsweb.com/diseases/syngamus-trachea-d75.html#effects