topworking

/ˈtɑpˌwɜrkɪŋ/
noun
  1. A horticultural technique of grafting new branches onto the top of an established tree to change its variety or improve fruit production.
    • Topworking is often done in early spring when the tree is dormant.
    • After topworking, the tree produced better fruit within two years.
    • The farmer used topworking to turn his old apple tree into a new variety.