Our greater family once owned 2,000 acres of farm & ranch land in the eastern Colorado plains. We're now down to 400 acres, which we lease the pastures for cattle grazing. The extended family has battled weeds since the late 1800's. The only way a weed will die is if the root is killed or physically removed. Future weed generations are stopped by not letting the plants go to seed, and by slowly exhausting the seed stock already in the ground over the years. Or decades.

Vinegar rarely kills a weed's roots, unless the roots are really shallow. Vinegar burns the plant tissue it touches, but the vinegar itself is not transported to the rest of the plant. Think of it as a topical lotion for animals -- it only affects the skin it touches. If you want to really affect the animal, the chemical needs to be transported throughout the animal via the bloodstream.

Good herbicides work because the plant moves the chemical throughout it system -- affecting leaves, stems, and/or roots. The herbicides often accelerate growth so the plant grows itself to death, or blocks a pattern of growth or nutrient transportation. The brand of the herbicide isn't important, but the chemical and its concentration are. Common weed chems include:
- 2,4-D
- Aminopyralid
- Dicamba
- Clopyralid
- Metsulfuron methyl
We've used all of these, and they all work. For the past few years we've gone with a mixture of 2,4-D, Aminopyralid, and Mesulfuron.

If woody plants are more of an issue, triclopyr is a good chem. But it also kills trees, and you definitely don't want it in your eyes.

Glyphosate is a non-selective plant killer. This means it kills everything. The chems I list above are selective, meaning they don't kill grass but work really well on broadleaf weeds. We won't use glyphosate on our ranch.

We have a no-chems veg-head neighbor who tries to control their weeds on some 15-20 acres with vinegar and digging. It doesn't work very well for them. Last month he commented on how good our naturally dry west pasture looks, even in this horribly dry year. Hardly a weed in sight on our 110 acres. His land looks like crap.

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Para -- my apologies. I didn't notice the date of the original thread, just that of the latest post.