oat crown rust

1. Will rust on oats hurt cattle?
2. Is Puccinia a rusty fungus?

Will rust on oats hurt cattle?

Oat fields affected by rust can suffer drastic declines in yield. Some fungal infections of grains and forages can certainly affect livestock, but crown rust of oats does not appear to be one of them. ... If rust-affected oat hay is to be fed to horses, moistening the forage should be considered when its fed indoors.

Is Puccinia a rusty fungus?

Each spore type is very host specific, and can typically infect only one kind of plant. Rust fungi are obligate plant pathogens that only infect living plants.
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Rust (fungus)