Effect of Cover Crops on Foliar Nitrogen of Apple Trees (from Bould and Jarrett. 1962)
| Treatment and Year | Foliar N (as % dry weight) of Apple Trees |
|---|---|
| 1954 (cultivated soil) | 2.49 |
| 1955 (T. repens) | 1.70 |
| 1956 (T. repens) | 2.24 |
| 1957 (T. repens) | 2.62 |
| 1958 (T. repens) | 2.92 |
| 1954 (cultivated soil) | 2.55 |
| 1955 (natural sward) | 1.77 |
| 1956 (natural sward) | 1.90 |
| 1957 (natural sward) | 2.10 |
| 1958 (natural sward) | 2.31 |
| 1954 (cultivated soil) | 2.53 |
| 1955 (P. pratensis L.) | 1.67 |
| 1956 (P. pratensis L.) | 1.48 |
| 1957 (P. pratensis L.) | 1.56 |
| 1958 (P. pratensis L.) | 2.04 |
| 1954 (cultivated soil) | 2.48 |
| 1955 (L. perenne) | 1.60 |
| 1956 (P. perenne) | 1.28 |
| 1957 (L. perenne) | 1.46 |
| 1958 (L. perenne) | 2.04 |