The Ranfurly Shield, colloquially known as the Log o' Wood, is perhaps the most prestigious trophy in New Zealand's domestic rugby union competition. First played for in 1904, the Ranfurly Shield is based on a challenge system, rather than a league or knockout competition as with most football trophies. The holding union must defend the Shield in challenge matches, and if a challenger defeats them, they become the new holder of the Shield.
Six different unions held the Ranfurly Shield between 1930 and 1939.
| Union | Won | Successful defences | |
|---|---|---|---|
| Held at beginning of decade | 3 | ||
| 3 September 1930 | 1 | ||
| 22 August 1931 | 15 | ||
| 21 July 1934 | 2 | ||
| 8 September 1934 | 1 | ||
| 10 August 1935 | 4 | ||
| 21 September 1935 | 8 | ||
| 31 July 1937 | 0 | ||
| 30 July 1938 | 5 | ||
| 10 September 1938 | 6 |
Book: Knight, Lindsay . 1980 . Shield Fever . Rugby Press . 0-9597553-8-1.