Yes, monocot roots are known to have polyarch vascular bundles. Monocot roots are known for the scattered vascular bundles (the xylem and phloem) that they have, which are normally arranged in the ring system. Dicot roots have the xylem within the center and the phloem exactly outside the xylem. Examples of the monocot roots include onions, garlics, tulips, lillies, etc.