Deep-Planting Willow Cuttings via Water Jetting

Planting willow cuttings for streambank erosion control is an ancient technology, revived in recent decades as part of "bioengineering." Problems include difficulties with emplacement, and slumping can easily undermine the short cuttings normally used. We have implemented a new hydraulic jetting technique which can rapidly (20–30 seconds) open planting holes in silty/sandy streambank alluvium, which are 2 meters deep by 3–5 cm diameter. Slender dormant willow cuttings pushed into these holes extend to damp soil and can sprout roots their entire below-ground length. The technology consists of a specially machined jetting tip welded to a 2 meter length of ordinary 1.3 cm ½ inch) steel pipe. Two of these jetting pipes are connected to a portable high-pressure pump, drawing water from the stream and delivering it to the jets via sturdy garden hoses. A planting team of 4 is most efficient, with 2 persons jetting holes and 2 planting willows. At favorable locations, a team of 4 can harvest 1000–1500 slender willow cuttings per day and deep plant 1000 cuttings per day. All the equipment is portable and can be carried on muddy stream banks. The jetting equipment plus 1000 bundled willow cuttings fit into a pickup truck. When properly planted, survival rates for fully dormant spring plantings of sandbar willow consistently exceed 95% in Iowa.