While being semi-parasitic on grass and other plant life, don't instantly dismiss the potential health benefits of wildly spreading Euphrasia. For this flowering plant is better known to many as 'eyebright' thanks to it's centuries of use as a natural remedy for common Eye infections.
When applied directly to the eye in the form of an eye bath or lotion, euphrasia may help to treat conjunctivitis or reduce other similar conditions whereby the eyes become inflamed, stressed and/or tired.
This tends to vary and really comes down to how you intend to use your euphrasia/eyebright remedy. For conjunctivitis, it is estimated that euphrasia would have resolved the condition within a two week period.
To support the health of your eyes you should consider supplementing with the carotenoids Lutein and zeaxanthin. Zinc, which is found naturally in the eyes, may also prove beneficial, as might a rich source of omega 3 Essential Fatty Acids and the Vitamins C & B1.
Yes it appears so! Especially when you consider that eyebright is a regular component of many of the conventional dry eye drops out there on pharmacy shelves today.
Euphrasia is no natural miracle cure so when manufacturers of eyebright drops say 'may improve eyesight', this is in the context of a minor eye related infection. It will not improve long standing eye issues, such as macular degeneration (AMD) that tends to occur as we get older.