Answer: You'll want to eliminate one of the stems and then stake the remaining stem so it grows upright. Redbud naturally grows as a multiple-trunked shrubby tree but with some direction it can grow into a single-trunked tree. Choose the straightest, healthiest looking upright stem to save and cut the other one off just above ground level. Use sharp pruners and cut at a 45 degree angle so water runs off the stump if it gets wet. Then drive a metal or wood stake into the ground a few inches from the stem you saved and use plastic garden tape to secure it to the stake. Wrap the tape around the stem and then around the stake in one or two places to hold the stem straight. Be careful not to tie it too tight. Check the ties once a month and loosen or remove and replace as the stem grows. Give your plant a deep soaking once each week and it should grow well for you. If another stem appears from the roots, cut it off as soon as you see it. Likewise for anything that sprout low down on the stem that you're trying to grow into a trunk.
Best wishes with your project!
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