We have our share of invasive Scotch broom (Cytisus scoparius) on our new property and we've been trying to figure out how to best make use of all that organic matter to try and bring it under a semblance of control. We finally got a whole whack-a-do chipped with the idea of adding it to compost as woody matter to increase the fungal content, and also as garden mulch around plants. Then someone went and said that it secretes a tar that is toxic to other plants. I have never heard of this. From my research I've only found reference to this once, here: The drive to sweep away scotch broom - Arrow Lakes News and I'm not sure if this is reliable, or if they're maybe mistaking Scotch broom for something else. I turn to you, Knowledgeable Ones, for any insights you might have before I make a terrible mistake and ruin both my compost and garden with potentially harmful plant matter.