It sounds like you are already on the right track. I'll leave it to subsequent posters to add exceptions to the rule, but basically, a prairie lacks trees. Cutting buckthorn is a great first step.

The best thing you can do for a prairie is to burn it in a safe and responsible manner. That is not possible in every neighborhood, but it does things like blacken the soil and create seedbeds for prairie plants that will not reproduce well without fire.

If fire is not an option, you will want to mow or graze the field periodically, as necessary to kill trees and shrubs. Best time to mow is August/September - maybe every three years or so. More if tree seedlings are problematic.

Most of the prairie plants biomass is in the roots. Cutting or burning is like picking an apple off a tree. No real harm. But shade will kill a prairie.

Oh, and no fertilizer, compost, manure, etc. That only favors weeds, shrubs, and trees. Many corporate campuses are converting acres of lawn to prairie because there is so much less cost, so much less to do to maintain a prairie.

I would also suggest learning what non-native exotic plants (other than buckthorn) grow in your area. Then watch for them in your prairie.

Hi, how great it is to see someone with prairie. We planted three+ acres last winter and expect good things in the spring. Last week we purchased 15 acres adjacent to us that is in native tall grass and is magnificant. We did a burn last spring and will burn every spring from here on. Here is my suggestio, buy "The Tallgrass Restoration Handbook" by Packard and Mutel and read it. It is chuck full of information for us beginners. I have learned so much from it and a friend that has about 30 acres of prairie. Check and see if there are any clubs or associations in your state. For example, in Ohio we have Ohio Prairie Association. When i was planting last winter I communicated with their president frequently about how to and what not to do. Best wishes, You won't be sorry that you kept it. And remember, burn this spring. Regards, Greg

One thing I would add, for greater diversity, burn at different times of the year, not always in the spring. Different times of burning favor different plants.

We just finished planting a 7 acre prairie about a month ago. The cover crop we used was oats and now the height of the oats has reached about 8-10 inches. At what point should we mow it?

My lawn here is just pasture. It has lots of wild flowers in spring/early summer. No mowing is done till both the Blue-bonnets and Indian Blanket have bloomed, gone to seed, and seed have dried.
If you have native bunchgrass, you may need to limit the height and number of times you mow, so as not to overly stress the grass. Each type has different requirements.