Trout leads with 9 triples. Ellsbury and Gardner have 8. Trout is a righty and they are both lefties. Trout has 82 walks and Cabrera has 77.
in 1876, Barnes had 14 triples, leading by 1. He had 20 BBs, leading by 5. He played only 66 games since the schedule was shorter and maybe it was still 8 balls for a walk.
In 1955, Mantle tied teammate Andy Carey with 11 triples. He led with 113 walks. Billy Goodman was 2nd with 99. Ted Williams had 91 walks in 98 games.
In 1958, Ashburn was 31 and led in triples for the second time with 13. Three other guys had 11. He beat Johnny Temple in walks 97-91. He led the NL in walks 4 times.
In 1964, Santo tied Dick Allen with 13 triples (Allen is listed below because he led the AL in walks once). My guess is that it is hard for a righty in Wrigley Field to lead the league. Santo beat Eddie Mathews in walks 86-85.
Here is a list of all the players to ever lead the league in both walks and triples, although not necessarily in the same season. A very impressive list
ARKY VAUGHAN 3 each, led in 3B one year then 3 in a row for BB then 3B the next year
DICK ALLEN different leagues 1each
FRED CLARKE At age 33 led in 3B, age 36 BB 1 each (playing in Pitt. maybe helped)
JIM GILLIAM 17 3B in rookie year, never again in double figures
JIM O'ROURKE led with 20 BB in 1877
JOE MORGAN led NL in walks as 21 year old rookie
MAX CAREY Twice led in each, BB at age 32 then 3B at 33
MICKEY MANTLE Both in 1955
RICHIE ASHBURN Both in 1958 at age 31, 4 times in BBs, 2 in 3Bs
ROGERS HORNSBY 2 in 3Bs, 3 in BBs
RON SANTO both in 64
ROSS BARNES Led NA in both in 1873, too
STAN MUSIAL 5 in 3B
TOM YORKWILLIE MAYS 3 times in 3Bs, 1 in BBs, age 40