The influence of calcium spray fertilization on the freezing temperature (°C) causing 50% electrolyte leakage (LT50) from leaf tissue of evergreen oak (Quercus ilex L.) growing under field conditions.z
| Treatment | 18 December 2004 | 18 January 2005 | 9 February 2005 |
|---|---|---|---|
| Control | −5.5 (22) | −6.2 (21) | −5.7 (22) |
| Silwett | −5.7 (22) | −5.9 (21) | −5.4 (22) |
| Calcium chloride | −6.2* (21) | −6.8* (20) | −7.2* (19) |
| Calcium sulphate | −5.7 (22) | −7.1* (19) | −7.1* (19) |
| Calcium nitrate | −6.7* (20) | −6.9* (20) | −6.5* (20) |
| Calcium nitrate borate | −7.6* (18) | −7.6* (18) | −6.7* (20) |
| Calcium hydroxide | −6.9* (20) | −7.7* (18) | −7.7* (18) |
| Calcium metalosate | −5.9* (21) | −6.4 (21) | −7.3* (19) |
| Calcium–magnesium complex | −6.4* (21) | −6.8* (20) | −6.9* (20) |
↵zMeans that are significantly different from the control using Duncan’s Multiple Range Test (P = 0.05) are indicated with an asterisk.
All values mean of eight trees, six leaves per tree.
Values in parenthesis = °F (two significant figures).