Grass

0.1-2.5 usd/kg
Circularity potential
Very high
Strength
Medium
Production energy
Ultra low
Stiffness
Medium
Embodied CO2
Ultra low
Density
Medium

The stems of many different types of grass, seagrass, rush, bulrush and sedge, are used to make fibres for textiles. They have not been exploited to the same extent as specialist fibre yielding plants such as flax, ramie and hemp, but nonetheless remain an important source of material for some industries. In our search for more sustainable fashion, furniture and construction, these plants offer materials that are both renewable and steeped in tradition.

Used mainly in handicraft, millinery (hat making), upholstery, matting (tatami) and baskets, each type has a particular use and method of application. Taking advantage of their unique properties takes a great deal of skill and labour and so in most cases, they have been superseded by synthetic alternatives. Polypropylene (PP), for example, is spun as a fibre, textured and dyed to mimic natural fibres. It is inexpensive and the properties may be tailored to the requirements of an application. Paper is slit and twisted to mimic sedge and rush. Produced on an industrial scale, readily available and low cost, these manmade alternatives have become hard to beat.



Stems of flowering plants tend to be hollow, with solid nodes where the leaves grow from. Strong fibres run the length of the stem, whose purpose it to keep the stem upright and resist natural forces. They are strong and stiff, but often degraded during processing and so yield a soft but weak fibre.

They are not as long, strong or fine as the more established bast textile fibres, and so tend to be harvested and used as is, while still ‘green’, or dried and dyed. Like hemp, the fibres are used to make insulation fabrics and panels. They offer a sustainable and renewable alternative to synthetic alternatives.


Design properties
Cost usd/kg
0.1-2.5
Embodied energy MJ/kg
2.5-15
Carbon footprint kgCO2e/kg
0.1-0.5
Density kg/m3
1300-1500
Tensile modulus GPa
6-25
Tensile strength MPa
5-300
Hardness Mohs
1
Temperature min-max °C
-40 to 150
Thermal
insulator
Electrical
insulator