Undergrowth density and plant spacing reveal local rainfall levels

Evidence

There are many other signs to watch for that tell us about the effects of climate. For example, many ferns, much moss, and many large-leaved vines in the undergrowth of a forest are a sign of heavy rainfall in the area. Widely spaced trees with few shrubs below them tell us that here the rainfall is probably rather low or between 15 and 30 inches a year. Still more widely spaced desert trees with numerous spines, such as the saguaro cacti and the Joshua trees in the southwest deserts (see Desert Woodlands under Deciduous Forests of the West in Chapter 8), tell us of extreme desert conditions with rainfall usually well below 10 inches a year. — Vinson Brown, Reading the Woods, 122

Categorization

• XREF: Directly feeds the field-observation assignment: reading vegetation structure as a proxy for moisture regime, a technique usable on any Minnesota transect. — connects to: Climate, animals, fire, and people all shape which plants grow where — Vinson Brown, Reading the Woods: Seeing More in…, 70; Ring width records year-to-year moisture and reveals cyclic drought patterns. — Vinson Brown, Reading the Woods: Seeing More in…, 119; Plant communities define distinct climatic life zones across latituderable and elevation gradients. — Vinson Brown, Reading the Woods: Seeing More in…, 102 (+2 more)
• SEED: Angle: ‘Your forest is a rain gauge’ — how spacing, moss, and fern cover let you estimate precipitation without instruments.

Broader Connections

• Harvesting crowded central clonal plants improves remaining plant growth #complicates (0.90) — Robin Wall Kimmerer, Braiding Sweetgrass, 636