I had some top soil brought in to my yard to make a garden. The native soil is red shale, so I needed good dirt. I also added some old wood mulch from a saw mill to break up the new soil, which contains a lot of clay.

I had some of the soil put in holes for future tree panting, and had some soil left over, that I left in a pile. The garden was tilled, including the wood mulch, and I planted greens in half the garden and left the other half unplanted.

I put in a gravity fed watering system with rain water, and left town for one month. When I returned, the greens were doing great, but everywhere I had added the wood mulch were the mystery weeds. They were thick and very happy. The dirt pile and tree holes did not have any of these weeds, nor were they anywhere else in my yard. My only conclusion is that the weed seeds were in the wood mulch that I bought from the saw mill. The mill person told me the mulch was from an old chip pile from the mill.

These weeds have grown to about two feet tall, have narrow seed tastles at the top, and thorns on the stem where side branches grow. The root is white and is shaped like a carrot. It is about six inches long. The stalk is green and is easily broken when trying to pull the plant out. I have dug all of them up and I think I caught them before they went to seed. The seeds are there on long narrow tastles, but I think not mature yet.

I am including a link to pictures if I can.

http://www.bubbleshare.com/album/480588.6d91e11ec5a/overview#16790369

Please help me identify this monster. I am afraid there may be many more seeds that did not germinate once the first plants took the sun light from the ground.

Extreme western North Carolina. Elevation 2100 ft.

Mulch came from about 1000 ft elevation.

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