Pools and streams and springs course and seep and drip. The waters sparkle with clarity and are achingly cold. Moisture glazes the rocks with an ineffable shine. The air is scented with wet, the tread underfoot softened with it. The tiered branches and filtered light create a realm of soft sounds and the feeling of a living dream of green, blue and brown, one ridge and hill of forest easing to the next. There are trees from sprouts to the ancients that have gained a look attained only at great age. Their bark flakes and shreds, and trunks soar to an apse raised over centuries. The soil is darker than coffee grounds, inky, sweet and redolent of fructifying forest funk. "This is the gold," [forest ecology professor Suzanne] Simard said, as she crumbled the soil in her hands, and teased apart filaments within it, finer than a human hair. These are fungal threads. Simard discovered in pioneering research they wind through these soils in a web of connections from tree to tree, sharing nutrients and water. Simard and others have revealed that trees also can recognize their own kin in seedlings they preferentially shuttle nutrients to, through the fungal network. In research published in the New Phytologist in 2016, Simard and her collaborators demonstrated carbon transfer " crucial food " was three to four times greater in kin than in nonkin pairings of Douglas fir seedlings. Kinship increased both the likelihood of establishment of a symbiotic relationship between kin linked by a fungal network, and its robustness.