Caragana bushes are shrubs or small trees, originally from Siberia, used in landscaping to create hedgerows. Unfortunately, when planted in an environment consistent with savannas or woodlands, Caragana bushes can overpopulate an area, spreading to the point where the bushes push out native species. It may take several years to get rid of caragana, combining extensive pruning with burning and herbicides to kill enough of the plant so that the roots rot away. It's a long and drawn out process, but in the end, you'll regain your land for other uses, and the caragena bush will be nothing more than mulch.
Cut down the caragana bush with pruning shears until only a 3-inch section of stems remains.
Burn the tip of the stems with a hand-held propane torch to prevent regrowth from the stems.
Apply an herbicide, such as glyphosate or triclopyr, to the area to prevent new stems from developing. Follow the herbicide manufacturer's application instructions carefully, making sure to cover your skin and wear a face mask before spraying.
Examine the ground closely for any new seedlings from the plant. Pull any seedlings from the ground by hand, making sure to pull up the entire root ball. Spray the seedling area with the herbicide as well.
Mow the area frequently during the month of June, cutting down any new sprouts as they occur.
Continue the removal and spraying process each year until the bush stops growing. The roots will eventually rot in place.