Heres my style for what its worth ,I take three or four lengths of round rod sized to load and lengths eyeballed to what you envision the three or four or ?? different main branch lengths to finish out at .Hammer out ends to taper three or four similar length for roots taper hammer long ends to suit envisioning,Bend roots at 90 degrees and fan out to form base wire group together and weld bottom gap pick trunk height desired and spot weld around, stick trunk end in forgeup to roots to heat all or as much of trunk as possible when hot stick in vice and twist rods to suit. If still hot enough make first bends on branches. Then break out the rosebud, heat and bend roots to suit,then tack weld roots to floor plate or work bench use rosebud to heat and bend branches to suit your vision,weld on extra forged branches if/as needed and/or leaves or whatever you can envision...(love that word)
hope this helps...cliff