Why is ragweed growing in my food plot even though I sprayed Roundup?

By Grant Woods,

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I have bunch of this growing in a new food lot that we planted this spring, and I cant figure out what this is. I don’t think its a weed as we sprayed round up twice and let it get nice and crispy before discing up the land. Any input would be appreciated.

The plant in your picture appears to be ragweed.

The active ingredient in Roundup is glyphosate.  Glyphosate is only active on living leaf surface area.  It won’t prevent weed seeds that are in the soil from germinating.  Disking often results in bringing weed seeds within the top inch of soil. These seeds will usually rapidly germinate.  It’s rarely necessary to spray Roundup before disking as disking will remove the weeds and Roundup won’t keep existing weed seeds from germinating!