Fig. 4 (a) Total phenolic content of 200 g soil amended with four levels of leaf litter leachates of Kalmia angustifolia. A 5, 10, 15, and 25 g of K. angustifolia leaf litter was soaked in 400 mL of water to get different levels of leachate. Reproduced with permission from National Research Council Canada (Inderjit and Mallik, 1996); (b) total phenolic content of soil infested with K. angustifolia from uncut and cut black spruce forest and K. angustifolia–free soil from uncut black spruce forest. Similar letters indicate significant (p < 0.05) differences between values. Reproduced with permission from the editor of Acta Oecologia (Inderjit and Mallik, 1999)
