Camelthorn rizomes growing inside/through house walls and floor
Thank you for your question for eXtension. I have heard of this happening a few times before. I am not an expert with camelthorn management, but there must be part of the plant that is growing outdoors where it gets sun. Camelthorn is a perennial with lots of underground rhizomes. It might help to start treating the outdoor population with a translocated herbicide. This should have the effect of limiting the availability of sugar to the indoor portions of the plant. The indoor portions cannot make enough sugar to sustain them without sunlight. The outdoor plants are supplying the sugars to the indoor ones through their connected roots. A University of Nevada publication on Camelthorn (http://www.unce.unr.edu/publications/files/nr/2002/FS0241.pdf) recommends "Picloram (Tordon and Grazon) applied at 1 lb/acre is one of the
most effective chemical control options." The herbicide will likely have little effect on dormant plants and this particular active ingredient might require a licensed structural pesticide applicator to do the job. Please read this publication and consider this treatment option.