too excited due to the grass

[horsegirl]

Is there anything I can do to counteract over excitement caused by too much sugary grass? (apart from restricting the grass) And am I cruel to consider a grazing muzzle thingy as he is almost unrideable when he has been out all day? Eyes on stalks, spooks at anything/everything/snorts/dances around tail up head in the air?

 

[Nudibranch]

Having similar problems. Apparently lack of magnesium in spring grass is the cause, farmers often supplement their livestock. Try Magic...someone suggested magnesium sulphate has the same effect, i.e. epsom salts but I'm a bit dubious about that. Anyone have any thoughts on that one?