I asked Joel Salatin this question when he gave a conference in Moscow, ID and he said it was different from area to area. He mentioned dandelions and plantain which I suspect we all have. The thing is, we're starting with bare existing ground and we can plant anything we want on it to get it established before introducing grazers. You can purchase seed from lots of places and I have a perennial patch of comfrey I can insert. Can you give us some ideas of what is in the salad pasture of yours? Much appreciated.
Dr. Denice Moffat & Michael Robison
Hi Denice, I've answered a similar question in this thread, so I'll just provide the link, and a highlight below of part of the answer most relevant to your situation.
Different plants will do best in different regions. Furthermore, it is about matching the right grass species to your particular grazing goals. Start by making a very clear farm plan for your cattle farm. The ideal hay mix is going to be different than a pasture mix for a summer grazing program, while a winter grazing program will benefit from adding yet other plants to the mix to provide plants that are strong to stand up through snow and are more resistant to leaching. And then go to your seed supplier to put together a mix that specifically caters to those needs. Also ask your neighbors what is thriving on their farms - and make sure you include lots of those species in your mix. No matter how wonderful a plant looks on paper, if it doesn't like your soil/climate/environment, it isn't going to be much use.
Be sure to include plenty of weeds, herbs, and poisonous plants. Animals have instincts and therefore know how to self medicate. and as long as they are not forced to eat those poisonous plants they will be healthier than if they were not present.
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