Tall unbranched invasive weed
This weed was well behaved for years; it grew, it died, we cut off the dead branches, it grew again. This year we had a wet summer with great reasons, and suddenly we have hundreds of these. They have invaded our natural Hillside, thriving under trees in the shade. This is not a bush, the branches grow from a central point in the ground and straight up. There are about 6 or 8 branches per plant. They grow about 5 to 6 ft tall, and the new volunteers are two to three feet tall and they are flowering also this year. We don't know what the flowers look like, I think that they're very small and unobtrusive and green.
Yavapai County Arizona
Thanks for contacting Yavapai County Cooperative Extension. I think you will need to bring a sample to one of our offices. It would be best if the plant were in flower, even if small and nondescript, the flower helps us determine the family. We have offices in Prescott and Camp Verde and are open M-F 9 am to noon and 1 to 4 pm. You may see the exact locations and contact information at our website: https://extension.arizona.edu/yavapai. Please email me at firstname.lastname@example.org with any additional information. The Yavapai County Fair is about to start up outside our Prescott office, so it would be best for you to visit the Prescott Office on or after 9/11/17.