Table 3.
Phosphorus (P) applications to the Rothamsted and Woburn long-term liming experiments, 1962–1996.
| Harvest yeara | P applied (kg P ha−1 yr−1) | ||||
|---|---|---|---|---|---|
| 1962–1980: | Control (0) | +P | |||
| 1962–1978b | 0 | 27.5 | |||
| 1968, 1974c | 0 | 55.0 | |||
| TOTAL 1962–1980: kg P ha−1 | 0 | 495 | |||
| 1981–1996d: | Control (P0) | P1 | P2 | P3 | |
| 1981 | Rothamsted | 0 | 25 | 25 | 75 |
| Woburn | 0 | 25 | 25 | 75 | |
| 1982 | Rothamsted | 0 | 50 | 0 | 50 |
| Woburn | 0 | 50 | 0 | 50 | |
| 1983 | Rothamsted | 0 | 0 | 50 | 50 |
| Woburn | 0 | 50 | 50 | 100 | |
| 1988 | Rothamsted | 0 | 25 | 25 | 75 |
| Woburn | 0 | 25 | 25 | 75 | |
| TOTAL 1981–1996: kg P ha−1 | |||||
| Rothamsted | 0 | 100 | 100 | 250 | |
| Woburn | 0 | 150 | 100 | 300 | |
a
P applied in the spring, except for Woburn 1964 and 1981, and Rothamsted 1981 and 1988, when applied the previous autumn.
b
No P applied in the fallow years 1969, 1979, 1980.
c
Higher P rate applied to potatoes in 1968 and 1974.
d
From 1981 onwards the two P treatments (control, +P) were divided into four P treatments (control, P1, P2 and P3). Eight of the control plots were made into a new control (P0) and the other eight became a P1 treatment, similarly the +P plots were made into P2 and P3 treatments. P was applied in the four years indicated, with no P applied 1989–1996.