Grass climatic and anatomical data

Members of the grass family Poaceae have adapted to a wide range of
habitats and disturbance regimes across the planet. The cellular structure
and arrangements of leaves can help explain how plants survive in
different climates, but these traits are rarely measured in grasses.
Further, most studies are focused on individual species or distantly
related species within Poaceae.  While this focus can reveal
broad adaptations, it also likely to overlook subtle adaptations within
more closely-related groups (subfamilies, tribes). This study therefore
investigated the scaling relationships between leaf size, vein density,
and vessel size in five genera within the subfamily Pooideae. The
relationship between leaf area and major vein number was consistent with
previous findings (p < 0.05, slope = 0.72 +/- 0.24), as was the
scaling coefficient of VLA (slope= -0.46 +/- 0.21). However, several
genera exhibited novel anatomical relationships. In Poa and Elymus, minor
vein number and leaf length were uncorrelated, whereas in Festuca these
traits were positively correlated (slope = 0.82 +/- 0.8). These findings
suggest there is important broad-scale and fine-scale variation in leaf
hydraulic traits among grasses. Thus, future studies should consider both
narrow and broad phylogenetic gradients.