canary reed grass toxic ???

Recently a horse customer of mine told me that canary reed grass is toxic and kills animals. I looked it up online but was left with more questions than answers. All the information i could find and only on horse websites said that  

 

 Sometimes known as Reed Canary Grass. PHALARIS can harbour toxic alkaloids which cause a serious nervous syndrome and Phalaris staggers. Seasonal and weather patterns appear to affect alkaloid concentration, as most toxicity occurs in autumn and in times of drought. Regrowth after grazing or mowing also shows a considerable increase in alkaloids.

Often found on the edges of ditches and lakes. Best eliminated and certainly not to be sown.

 

but the next site says ( a vet site)

I have searched my references and the
toxic plant links in the Contents of
this site and I could not find any
reference to canary grass being toxic. 

 

So my question is is it toxic ? and if so how bad ?  

We are having a rough year this year it has been very dry , and i have been bailing up all i can get including canary reed grass. People in this area have been feeding these grasses for years and no problems yet that I know of so is this just an other example of horse gals that heard from a friend of a friend of a friend ... and don't know there stuff ? or is it real

 

canary reed grass toxic ???