Traits of absorptive fine roots that were related to a 'do-it-yourself' strategy (high specific root length, low diameter, low mycorrhization) were associated with higher tree growth. For transport fine roots, these traits did not relate to growth rate. Does that mean, transport roots don't matter?
Comments
With higher root order, traits but also the function of the roots change. However, many of the commonly measured fine root traits are proxies of nutrient uptake, soil exploration or mycorrhizal collaboration (all of which mostly happening in lower order roots).
2)Approaches based on root orders are not perfect (because functioning of different orders is species-specific, see e.g. the high mycorrhization of 'transport roots'), but still provide higher resolution.