02/04/2024
In 2014 we analysed the mineral content (in collaboration with the organic chemistry department Bangor University) of 13 grass species including 3 Perennial Rye varieties, 2 which were bred for high sugar content and the other one was originally bred 40 years previously (identified by IBERS), the remaining 10 species were a mix of native grasses found in meadow and old lea pastures.
The individual grass species varied immensely in mineral levels, being higher in all species in those fields backing onto woodland or surrounded by a hedge.
The modern perennial ryegrasses were highest in iron and lowest in magnesium and lacked many other vital micronutrients, however, the mixed native grasses combined had higher and more balanced levels of minerals.
The reasons for this are not only found in the soil but in the rhizosphere and the hyphosphere of the plant roots, the place where minerals are stored and absorbed.
The rhizosphere is soil root interface it contains a variety of micro-organisms called mycorrhizal (the word means fungus-root) and is a rich place of nutrient manufacture and recycling which directly influences mineral levels.
The roots provide the fungus with glucose and sucrose, the grass sends the sugars from its leaves to the roots and out to the fungus. In return, the grass gains better access to water and the whole spectrum of minerals. Different grasses attract different communities of these microorganisms and create unique environments around themselves called hyphospheres. Many different grass species equals a higher and wider range of minerals, of much greater benefit to the horse.
A horse grazing in a field surrounded by a hedge or in a field containing trees will have better and more balanced mineral levels from the grass than those without. Three of the best trees to have either in the hedge or field are white willows, silver birch, and poplar, these trees encourage a varied community of microorganisms into the grass which will spread into the root systems across the whole field providing that field contains a mixed variety of grasses.
Tree root systems are incredibly important for the health of horse pasture as they are far-reaching and can spread their good bacteria and fungi across the pasture to improve the mineral levels of the horse as it grazes. Grass mixed with trees is likely to be healthier, contain better nutrients, have faster growth and perhaps more importantly will have a reduced sugar content as some of the sugar will go to the roots to feed the mycorrhizal.
Pasture and hay for that matter containing only one or two types of grass, particularly if they have been bred to hang onto their high sugar yield rather than translocate the sugar to the root system to feed the mycorrhizal community will not contain the spectrum of minerals that a meadow type of pasture will.
