Carbon Grass Technology

“Fixing” The Greenhouse Effect

Rigby Taylor and its seed-breeding partner Top Green have a long and very successful relationship. In France, situated at Les Allueds near Anger, Top Green’s seed breeding and research facility is the partnership development centre for Rigby Taylor grass seed mixtures, including the exciting development of Carbon4Grass

The greenhouse effect, carbon cycle and carbon sequestration impact our everyday lives. Grasses just like trees are chlorophyll-based plants, absorbing carbon dioxide (CO2) from the atmosphere for use in photosynthesis. This process uses sunlight and water to convert CO2 into carbohydrates and simple sugars to generate energy and growth, “fixing” greenhouse gases from the air into the soil by sequestration and providing oxygen as a bi-product.

Just two square metres of grassland can produce enough oxygen to support one person for an entire day, or for one hectare, 1 person for 13 years!

A proportion of the absorbed carbon is transferred from the dense canopy and fibrous root system into the soil as plants senesce and decompose. One hectare of natural, open grassland can sequester up to 2.5 tonnes of carbon per hectare per annum, creating a net carbon sink held within the soil profile.



All well and good but what about the intensively managed amenity grass surfaces we all enjoy which, by definition, have a much greater environmental impact than infrequently managed grassland? Because managed amenity turf has higher plant populations than natural grassland, having the availability of amenity cultivars which sequester (lock up) relatively more carbon can make a significant contribution in mitigating the environmental impact of essential maintenance inputs, preserving a net carbon sink.



A “Carbon4Grass” (C4g) study at Top Green Breeding & Research Station in Les Alleuds, France commenced in 2005. Using well-established grass plots, the initial aim was to identify differences in the carbon sequestration values of managed amenity grass species.

The study revealed significant differences between species in their capacity to store and sequester carbon within the leaves, roots and soil profile when managed under exactly the same environmental conditions*.



The study progressed to assess a range of cultivars within species, with new cultivars from the breeding programme entered into the study over time. The differences in proficiency of individual cultivars to sequester carbon proved to be significant. This knowledge has been used to create Rigby Taylor Carbon4Grass mixtures, combining increased levels of carbon sequestration potential with desirable amenity characteristics for a range of sports and landscape situation.

For example, low maintenance, slower growing cultivars with higher carbon ‘scores’ have been identified to help reduce the impact of tasks such as mowing, which contributes to the carbon footprint. The RT Low Maintenance mixture demonstrates the potential to sequester 80% more comparison with other comparative low maintenance landscape mixes.


Tetraploid Technology

A notable innovation for Carbon4Grass is hard wearing tetraploid perennial ryegrass technology, extending the growing season through cold temperature growth.

Tetraploids are actively germinating, growing and photosynthesising in colder conditions from just 40C, thus maintaining active grass cover for longer to potentially “capture” more carbon. Tetraploids (4n) have double the chromosomes of a diploid ryegrass (2n), meaning double the chloroplast and chlorophyll for photosynthesis. The root mass of grasses acts as a reservoir for carbon, which eventually transfers into the soil profile as roots die and decompose.

Tetraploids have a much stronger, deeper, denser root mass than diploids, delivering greater potential for higher sequestration, an important physiological feature when you consider ryegrass accounts for around 90 percent of the seeds used to create and maintain amenity turf in the UK. Tetraplois also have increased tolerance to disease and drought in comparison to diploids.

Potential is enhanced still further with Germin-8T seed treatment, which boosts germination and establishment particularly in cooler conditions. Germin-8T also contains both Mycorrhiza and Trichoderma atroviride for symbiotic plant health. Together with tetraploid technology it enables sowing of Carbon4Grass mixtures virtually all year round.



The past twelve months and the summer in particular, were a clear indicator if one were needed of how changes in climatic conditions are dramatically challenging and shaping our environment. It is within everyone’s duty of care to ensure we do the utmost to minimise or offset our carbon footprint. Seemingly insignificant choices can collectively make a meaningful contribution overall. Rigby Taylor offers a choice of Carbon4Grass cultivars with improved disease and drought tolerance to create bespoke mixtures for turf production.

Jayne Leyland: Seeds Product Manager. Rigby Taylor Ltd 


*The amount of carbon sequestered will vary depending on environmental conditions and maintenance inputs.