Secretion of GH by the pituitary into the bloodstream stimulates the liver to produce another hormone called insulin-like growth factor I (IGF-I). IGF-I is what actually causes tissue growth in the body. High levels of IGF-I, in turn, signal the pituitary to reduce GH production.
Site and Spacing. 1  The pawpaw is a small tree that typically grows to about 20 feet high and less broad. 2  In an orchard setting, tree centers should be at least 10 feet apart. Row widths depend on the size of tractors and equipment -- 20 foot rows may be a minimum width.
The name Paw Paw was derived from a nearby grove of Pawpaw trees on the edge of a 2,000-acre (8 km 2) forest. American general Winfield Scott is credited with being the first person of European ancestry to discover the area.