The crash and clean up are in the southbound lanes of I-59 at Highway 288.
ABC13 video shows large amounts of hay scattered along a stretch of the freeway, blocking lanes.
Around 6 a.m., Total Traffic reported delays of over 80 minutes due to the backup.
Houston police are responding to the scene.
It's unclear how the hay spill happened or how long it will take crews to clear the roadway.
This is a developing story. Eyewitness News is continuing to gather facts.
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