Our community development,, Spirits Reach, is restoring the native grasses in the disturbed soil areas of the development. Two years ago, the disturbed soil areas were hydroseeded with 5 native grasses. The black meddick seems to be overtaking most of the areas. We have pulled some plants. We are trying to avoid herbicide (to be chemical free). We have had a suggestion to use a fertilizer that would make the grasses grow but not the black meddick; change the composite of the soil. Will this idea work? Any suggestions on who/where to go to talk about this idea.
Adding nitrogen fertiliser might work, as Black Medick (only one 'd'!) is a nitrogen-fixing legume, so is most competitive in low nitrogen soils, least competitive in high nitrogen soils. But beware that adding lots of nitrogen fertiliser can have other less welcome side effects, including encouraging other invasive species to become dominant. I suspect the cure would likely be worse than the problem. My best suggestion is to keep hand-pulling; start early in the year (or even continue right through the winter) so as few plants as possible reach seed-bearing maturity.
