Development of two headers for a versatile woody brush harvester-baler.

In 2006, a willow harvester was developed with a 1.97-m wide four-saw cutter and a 1.55-m wide rotary shredder placed in front of an agricultural round baler. The header worked well in level plantations and left a clean-cut stump. However, it was not designed to operate on uneven land where rocks and soil might cause saw blade malfunction. For this reason, a second more robust header was developed in 2007 to harvest natural brushes on fallow land. The new header was a 2.30-m wide flail shredder that both cut and conditioned the woody brush before ejecting it into the baler. It was evaluated in two field trials in eastern Canada. On a fallow and poorly drained land, the shredder header-baler harvested natural alder shrubs at an average rate of 4 t wet matter (WM)/h. In a level willow plantation, the shredder header-baler worked up to 12 t WM/h, compared to 8 t WM/h with the original four-saw header-baler. The bales typically weighed 400 kg, were 1.4 m in diameter and 1.2 m wide; they had a wet density of 220 kg/m³ at 50% moisture on a wet basis. The two headers can be adapted to the same round baler and offer a versatile alternative to harvest either wild brushes or planted woody crops. The technology may improve land management and provide a new source of otherwise neglected biomass.