Playing through the greenery and litter of a mini forest’s undergrowth for just one month may be enough to change a child’s immune system, according to a small new experiment.  When daycare workers in Finland rolled out a lawn, planted forest undergrowth such as dwarf heather and blueberries, and allowed children to care for crops in planter boxes, the diversity of microbes in the guts and on the skin of young kids appeared healthier in a very short space of time. https://www.sciencealert.com/daycares-in-finland-built-a-backyard-forest-and-it-changed-children-s-immune-systems