The experiments with grass and clover at Boghall and
ryegrass at Bush showed that: -
1. the mineral content of different species of grass and
clover varied considerably, the clovers tending to be higher
in mineral content than the grasses.
2. the mineral content of white clover was affected by the
grass with which it was grown and the competition with the
grass for the available nutrients, particularly in the case
3. the mineral content of both grasses and clover varied
considerably from month to month, the nature of the variation
depending on the frequency of cutting. In grasses cut
monthly, the minerai content tended to increase towards the
end of the season, while in uncut ryegrass, the mineral
content decreased as the grass matured.
4. treatment with "nitrochalk" increased the calcium and
magnesium contents of grasses throughout the season, and
increased the phosphorus content initially. The effect of
treatment on the clover seemed to depend on the yield and
leafiness of the grass with which it was grown and the
consequent competition between the grass and clover.
5. treatment with heavy dressings of MgSO4.7H2O increased
he magnesium content of ryegrass throughout the season.
. the uptake of minerals varied from species to species
and from month to month throughout the season, the monthly
variation generally following that of the yield. The uptake
of minerals by clover was lower than that of the grasses
/because of the lower yield of the clover. The total seasonal
uptakes of calcium and of phosphorus were greater than the
uptake of magnesium.
7. treatment with "nitrochalk" increased the uptake of all
three elements by both grass and clover.
The mineral content of a sward will therefore depend on
the botanical composition of the sward, the frequency of
cutting, the time of year and tiffe fertiliser treatment.
The experiments with mixed herbage grown for hay and for
dried grass bore out these results and showed that: -
1. the magnesium content of the herbage depended on the
available magnesium in the soil.
2. the mineral content of herbage decreased with advancing
3. the effect of the fertilisers studied depended not only
on the nature of the fertiliser but also on the mineral status
of the soil to which it was applied and the existing cation:
(a) magnesium sulphate raised the magnesium content of
the herbage, particularly where the soil was low in available
(b) potassium sulphate depressed the magnesium and
phsophorus contents of herbage and in some cases the calcium
(c) potassium -magnesium sulphate had little effect on
the magnesium ani phosphorus contents of herbage, and was
therefore more suitable for use where the soil was low in
The experiments with turnips and kale showed that: -
1. the yield of dry matter and the uptake of minerals in
the leaf was less than that of the roots in turnips and of
the stem in kale.
2. the mineral content of the leaf was higher than that of
the roots in turnips and of the stem in kale.
3. the magnesium content of turnip leaves depended on the
available magnesium in the soil.
4. treatment with potassium -magnesium sulphate increased
¡the dry matter yield of turnip roots where the available
soil magnesium was low, and increased the yield of magnesium
content of kale leaves, and the uptake of magnesium by the