Chronic N Green Foliage Data 1988-1999, 2002 and 2005. Samples only collected every 3 years after 1999. Collected in late July or early August each year. Means and standard deviations of foliar samples measured as percent nitrogen, lignin and cellulose using near-infrared spectroscopy. Black Oak in Hardwood Plots. . indicates missing data point year treat species n av%n sd%n av%lig sd%lig av%cel sd%cel lig:N 1988 HC BO 4 1.94 0.03 26.52 1.84 43.17 0.68 13.70 1988 HH BO 4 1.95 0.15 25.58 1.81 40.83 1.39 13.14 1988 HL BO 4 2.00 0.15 24.69 0.70 44.07 0.43 12.35 1988 HS BO 4 1.82 0.18 25.16 1.19 41.14 1.80 13.83 1989 HC BO 4 2.10 0.09 24.49 1.29 43.54 2.24 11.65 1989 HH BO 4 2.31 0.12 27.05 1.17 41.46 1.09 11.73 1989 HL BO 4 2.21 0.04 24.55 1.02 43.20 1.58 11.12 1989 HS BO 4 2.27 0.06 26.08 1.08 43.57 0.57 11.50 1990 HC BO 4 2.37 0.01 24.62 0.51 42.33 0.73 10.40 1990 HH BO 4 2.64 0.30 25.48 0.84 43.67 1.07 9.67 1990 HL BO 4 2.41 0.08 23.86 0.30 43.58 1.33 9.91 1990 HS BO 4 2.42 0.06 25.49 0.29 44.73 0.69 10.52 1991 HC BO 4 1.88 0.04 26.15 1.21 41.54 1.89 13.93 1991 HH BO 4 2.34 0.16 26.84 0.07 41.92 0.75 11.46 1991 HL BO 4 2.02 0.07 27.06 0.60 43.89 0.87 13.39 1991 HS BO 4 1.96 0.12 25.51 2.49 40.65 1.39 13.00 1992 HC BO 4 2.25 0.05 25.72 0.38 42.80 0.32 11.42 1992 HH BO 4 2.58 0.05 26.42 0.86 40.17 0.59 10.24 1992 HL BO 4 2.16 0.03 25.63 1.92 40.39 2.26 11.89 1992 HS BO 4 2.25 0.13 26.55 1.60 40.29 3.60 11.80 1993 HC BO 4 2.18 0.10 24.44 0.77 43.86 0.88 11.24 1993 HH BO 4 2.74 0.21 26.29 1.31 42.27 1.33 9.60 1993 HL BO 4 2.34 0.05 24.26 1.99 41.34 2.24 10.38 1993 HS BO 4 2.32 0.14 24.15 1.58 41.67 1.43 10.41 1994 HC BO 4 2.26 0.18 24.63 1.62 41.72 1.97 10.90 1994 HH BO 4 2.79 0.20 25.70 2.30 41.30 1.33 9.22 1994 HL BO 4 2.46 0.06 23.41 0.66 43.38 0.75 9.52 1994 HS BO 4 2.42 0.11 23.93 1.47 42.36 1.45 9.90 1995 HC BO 4 2.25 0.11 24.44 1.14 43.80 0.58 10.86 1995 HH BO 4 2.75 0.38 26.90 2.31 41.52 0.60 9.80 1995 HL BO 4 2.32 0.06 23.54 0.54 43.71 0.49 10.16 1995 HS BO 4 2.24 0.08 24.84 0.46 42.14 0.63 11.10 1996 HC BO 4 2.58 0.08 25.98 0.78 45.11 0.57 10.08 1996 HH BO 4 2.91 0.15 27.93 0.29 41.50 1.08 9.61 1996 HL BO 4 2.72 0.14 27.03 0.62 43.93 1.55 9.93 1996 HS BO 4 2.66 0.16 26.82 0.71 43.18 1.94 10.10 1997 HC BO 4 2.27 0.05 24.63 0.47 40.46 0.88 10.86 1997 HH BO 4 2.81 0.10 24.17 0.85 38.99 1.13 8.61 1997 HL BO 4 2.50 0.21 22.55 0.59 41.34 0.62 9.02 1997 HS BO 4 2.41 0.08 23.47 0.98 39.92 1.75 9.73 1998 HC BO 4 2.20 0.10 28.00 1.14 39.41 0.41 12.73 1998 HH BO 4 2.89 0.23 28.85 1.27 38.75 0.82 9.97 1998 HL BO 4 2.54 0.09 27.76 0.82 40.83 0.44 10.95 1998 HS BO 4 2.43 0.09 26.85 2.31 39.99 1.00 11.05 1999 HC BO 6 2.35 0.21 26.28 1.89 44.49 2.35 11.20 1999 HH BO 6 3.13 0.22 28.63 0.98 39.16 1.32 9.16 1999 HL BO 8 2.64 0.19 27.82 1.03 42.59 2.49 10.54 1999 HS BO 6 2.62 0.05 27.00 1.41 39.09 1.62 10.29 2002 HC BO 10 2.35 0.13 26.56 1.76 40.20 1.97 11.32 2002 HH BO 10 2.93 0.26 30.34 2.30 37.14 2.08 10.37 2002 HL BO 10 2.66 0.14 28.28 1.07 39.41 1.59 10.64 2002 HS BO 10 2.50 0.11 28.35 1.75 38.35 1.64 11.35 2005 HC BO 10 2.48 0.16 26.60 1.38 42.39 2.50 17.13 2005 HH BO 10 3.08 0.25 28.95 1.65 38.89 1.27 12.61 2005 HL BO 9 2.70 0.18 25.61 0.98 41.41 1.69 15.33 2005 HS BO 5 2.39 0.23 26.62 1.17 38.02 1.47 15.91