Average soil moisture under various mulch materials. Soil moisture is tensiometer readings (the lower the value, the greater the soil moisture).
| Mulch | 1980 | |||||
|---|---|---|---|---|---|---|
| June 25 | July 9 | July 24 | July 31 | Aug. 25 | Sept. 4 | |
| Weed-Chek fiberglass | 32 | 100 | 29 | 33 | 6 | 0 |
| Wood chips | 6 | 85 | 17 | 60 | 14 | 0 |
| Hay | 22 | 100 | 52 | 100 | 45 | 0 |
| Turface | 51 | 100 | 50 | 62 | 24 | 0 |
| Redwood bark | 9 | 100 | 14 | 64 | 23 | 0 |
| Black plastic | 41 | 90 | 32 | 92 | 33 | 0 |
| No mulch | 63 | 100 | 16 | 100 | 36 | 0 |