Where do we expect to find deep plant roots?

Plant roots have been observed up to 70 meters in depth – What would compel a plant to root so deep? Earlier work shows that the climate, soil and drainage all affect rooting depth, but with conflicting results. For example, both the deepest and shallowest roots are found in arid regions. We compiled >2,400 globally distributed rooting-depth observations of individual plants and applied simple correlation analysis to assess the impact of global climate, local topography and substrate, and individual plant size, and their combinations controlling where and why plants root deep. The provided dataset includes 2,458 observations of maximum rooting depths of individual plants, and their abiotic and biotic variables across >130 plant families, including 2,021 observations from Fan et al. (2017)  and additional 437 observations synthesized as part of this study. Using this data, we found that at the global scale, deep roots are driven by climate. Both concentrated wet periods and pr..., , # Data from: Where do we expect to find deep plant roots?

Dataset DOI: [10.5061/dryad.mgqnk99bg](10.5061/dryad.mgqnk99bg)

## Description of the data and file structure

We compiled rooting depth observations from published literature, government papers, and unpublished theses and reports. We searched by key words such as “root”, “rooting depth”, and “root system” in Web of Science database and Digital Library of JSTOR ([http://about.jstor.org/](http://about.jstor.org/)), and found more reports through citations within the documents. Our compilation continues as more data come into light by incorporating international literature. The 2,458 entries of >1100 species we have compiled so far are given in a large table. We have also included a description of each variable, how it was compiled, and the reference for each observation.

We recorded the following information:

(A) Reference of data source (all included in the reference list at the end of this document)

(B) Geographic Location ...,