Certified GKH Gardening Expert
That is one of many Euphorbia. It will be hard to pin down the species, since there are many, and many of them look pretty close without genetic testing.
most of the Genus contains a toxic sap to some degree, with tree forms being far worse than plants. The thicker the sap, the more irritating it tends to be.
This genus contains trees, shrubs, cacti, succulents, weeds, and flowering plants, and is one of the most broad plant Genus around, so pinning them down is VERY difficult in some cases.
Digging them out before flowering is the best method of control. Broad leaf herbicides can be somewhat effective.
This collection of articles will offer information on many of the plants in the Genus: https://www.gardeningknowhow.com/ornamental/cacti-succulents/euphorbia