Sustainable forest biomass: a review of current residue harvesting guidelines

Table 9 Minimum harvest residue retention recommended in forest biomass harvesting guidelines, and definitions for coarse woody debris (CWD) when guidelines specifically referred to CWD as a component of harvest residue

	Minimum residue retention^a		Definition of CWD		CWD notes, position of diameter measurement
Jurisdiction	All residue (%)^b	Other (ha⁻¹)	Diameter (cm)	Length (m)	CWD notes, position of diameter measurement
PI		> 200 pieces CWD	> 7.5	> 2
AL			> 15.2
IN	20–33		> 15.2		Large end
KY	15–30		> 7.6	> 0.9	Small end
MA	25–100		> 7.6	> 0.9	Small end
MD	20–33		> 7.6–10.2		Large end
ME			> 10.2		Large end, dead and down
MI	17–33		> 15.2		Large end
MN	33		> 15.2		Large end
MO	33		> 15.2		Large end
NC			> 15.2		Large end
PA	15–30
SC	20–30		> 7.6		Dead and down
VT	20–33		> 7.6
VA			> 10.2		Inside bark
WI	10	11 t FWM^c	> 10.2		Small end, inside bark
NE-USA	25–33
PNW-USA^d	30–50
PNW-USA		10–20% cover CWD	> 15.2
PNW-USA		10–20% cover CWD^e	> 7.6	> 0.9	Small end, dead and down^g
PNW-USA		1–9% cover deadwood	> 12.7		Dead wood
SE-USA	33
UK	50-66^f	> 20 m³	> 10	> 1
SE	20		> 10
FI	30		> 10
LT		> 5 m³	> 10
Europe^h			> 10	> 2

^aSome jurisdictions or regions do not quantify retention thresholds, even if retention is recommended
^bProportion of total residue (%)
^cFWM: fine woody material
^dFWD only
^eWhere protection of small mammals and their predators is an objective
^fUSDA Forest Service definition; an alternate to the definition in the row above
^gFor the UK, 66% of brash or tops from trees < 7-cm dbh
^hMinimum diameter is at discretion of individual countries (European Environment Agency, available at https://www.eea.europa.eu/data-and-maps/indicators/forest-deadwood-1)

ISSN: 2192-0567