Answer:
加 KA, kuwa(eru), kuwa(waru) - add, append, join, take part
黄 KOU, OU, ki - yellow
支 SHI, sasa(eru) - branch, support
票 HYOU - paper slip, vote, ballot
古 KO, furu(i) - old
Adding a tree (木 MOKU, BOKU, ki - tree) to these characters lets them branch out in a new direction!
架 KA, ka(keru), ka(karu) - hang, build (a bridge)
横 OU, yoko - side
枝 SHI, eda - branch
標 HYOU - sign, mark
枯 ka(reru), ka(rasu) - wither