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Individual study: Root penetration of perennial rye-grass Lolium perenne on acidic colliery shale in response to fertilizer and limestone treatments, Lancashire, England

Published source details

Fitter A.H. & Bradshaw A.D. (1974) Root penetration of Lolium perenne on colliery shale in response to reclamation treatments. Journal of Applied Ecology, 11, 609-615


Colliery shale is very liable to drying out in its surface layers, even during relatively short periods of dry weather, thus good root growth is essential for successful reclamation. In this study, root penetration of perennial rye-grass Lolium perenne on colliery shale in response to fertilizer and limestone addition reclamation treatments were investigated in Lancashire, northwest England.

Perennial rye-grass Lolium perenne growth experiments were conducted in field plots on colliery shale spoil sites in south Lancashire, northwest England. Experiments were laid out using surface-applied agricultural limestone and fertilizers. Additional sets of plots were established with different amounts of phosphorous (P) from 0 to 100 kg/ha, added. From shale samples, pH, P, Ca, Mg, K and Na content were determined.

In a phosphate experiment a basal dressing of N, K, and limestone was applied.  Pots receiving no nutrients were used as a control.

Field plots were sampled in September 1971 and November 1971. Root penetration was also measured in a glasshouse the pot experiment after 20 weeks; pH was recorded at 0, 5, and 15 cm depth.

Fertilizer application rate was found to be more important for promoting root penetration than limestone addition in the field. In the glasshouse, however, pH was found to be limiting, with a critical value of about 4.1, below which root growth was severely inhibited.

In the phosphorous addition experiment, maximum root penetration coincided with maximum shoot growth. But penetration was poorer; this seemed to be due to the lower level of added nitrogen.

The authors suggest that there may be a direct stimulation of root growth by the presence of nutrients at a particular depth, and deep incorporation of fertilizers into colliery shales is therefore recommended.


Note: The compilation and addition of this summary was funded by the Journal of Applied Ecology (BES). If using or referring to this published study, please read and quote the original paper, this can be viewed at: