Barbula unguiculata (Bird's-Claw Beard-Moss)

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Barbula spp.

beard moss

Pottiaceae Cosmopolitan

Deer Resistant Drought Tolerant Container Friendly

Native to North America

SunPart Shade – Full Shade

WaterMedium · drought-tolerant

Overview

Barbula spp. is a large genus of small acrocarpous mosses in the family Pottiaceae, found on soil, rock, walls, and disturbed ground worldwide. Plants form low green to yellow-green turfs and cushions a fraction of an inch to about 1.5 inches (0.5-4 cm) tall, spreading into patches several inches across. The stems are erect and crowded, clothed in narrow, lance-shaped to tongue-shaped leaves 0.04-0.16 inch (1-4 mm) long. Leaf margins are often recurved, and the surface is roughened by tiny papillae; when dry, the leaves twist and curl inward, opening again when moistened. A midrib runs to or beyond the leaf tip, sometimes as a short point. Spore capsules, where produced, are held upright to slightly inclined on reddish stalks 0.2-0.8 inch (5-20 mm) tall, the cylindrical capsule topped by a lid and a twisted ring of teeth that controls spore release. Many species favour lime-rich or disturbed substrates and appear on mortar, paths, and bare soil. Plants are poikilohydric, drying to a dull, shrunken state and reviving with rain.

Native Range

The genus is cosmopolitan, with species on every continent including Antarctica, and is well represented across North America, Europe, and Asia. Plants colonize bare and disturbed ground, soil banks, rock crevices, walls, and mortar, often on calcareous or neutral substrates from sea level to high mountains.

Suggested Uses

Used in moss gardens, green roofs, terrariums, and between paving and on walls where a low green cover is wanted. Lime-tolerant species grow on stone, mortar, and concrete that suit few other mosses. Plants form a thin carpet in shaded, consistently moist spots but thin out under heavy foot traffic or deep shade with litter.

How to Identify

Recognized as small cushion- or turf-forming mosses with narrow, papillose leaves that twist and curl when dry and spread when wet. The leaf margins are commonly recurved and the midrib reaches or exceeds the leaf tip. Upright cylindrical spore capsules on reddish stalks, with a spirally twisted ring of peristome teeth, help separate Barbula spp. from similar Pottiaceae, though microscopic leaf characters are usually needed to name species.

Appearance

Colors

Fall Foliage Colors

no change

Detailed Descriptions

Foliage Description

green to yellow-green

Growing Conditions

Sun Requirements

SunPartial Shade SunFull Shade

Requires 1-5 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.5 - 8.0(Alkaline)

357912

Soil Types

loam clay rocky chalk

Drainagemoist

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

In cultivation for moss gardens and terrariums, plants grow on firm, moist, low-nutrient substrate in shade to part sun, with several species tolerating brighter, more exposed sites than most mosses. Steady surface moisture supports growth, while the plants survive repeated drying by going dormant and greening up again when rewetted. Lime-tolerant species establish on mortar, concrete, and calcareous soil where many mosses fail. Competition from vascular weeds and smothering leaf litter are the main problems, and patches are kept clear of debris. No feeding is needed, as excess nutrients encourage competing plants. Establishment is by transplanting fragments or by spreading a moss slurry onto a moist, compacted surface.