The researchers examined how the size and type of young trees can predict the amount of roots they have underground. They looked at data from 19 European datasets and found that tree height, diameter, and aboveground biomass can help estimate root biomass. Broadleaf trees tend to have more roots compared to conifer trees of the same size. As trees grow bigger, they allocate more biomass to their roots. Trees in more light tend to have a higher proportion of roots. Trees with a high height to diameter ratio are less stable and have less root biomass. Increasing light can help improve a tree's stability by increasing its root biomass.