Into the Woods solution
by Kegler

Eight answers gain a piece of wood before entry, as indicated by the unclued     
phrase at 25A: WELCOME A “BOARD”.  The added terms are shown in {}.

Into the Woods solution grid

Across
1TIFF(IN)S
6S + QUIp + BS
10S,L + IN + G
11TADPOLE ("PAD TOLL" spoonerism)
12{PLANK}TON (NOT rev)
15OMAR (hidden)
16DU(N)ES
17DON + ATE (TEA anag)
19{STUD}IO + U.S.
21ABE + T
22CROW(N)S
24PEA (odd letters)
25WELCOME A BOARD
26{SLAT}TERN ("TURN" hom)
29R(I + BB)ON
30EONS (NOSE anag)
34SUBMERGE (BEER MUGS anag)
36A + GAIN
37{PANEL}LED (2 defs)
39CAN + TEENS
40ME + OW
41EX + TINCT
42PURPLE ("PER PULL" hom)
Down
1TOP DRAWER (REWARD POT rev)
2F(L)AN
3FINES + T
4IN(K)S
5STOOD (TO-DOS anag)
6S + AN + D
7U(PO)N
8B{LATH}ERING ("BARING" hom)
9SERENA + D + E
10S{LUMBER}IN + G
13T + HU(R)MAN
14MOO + N{BEAM}
18CELEBRA(N)T (BRACELET anag)
20SPAN (NAPS rev)
22CO{LOG}N + E
23W + AT&T
27TRUmAN + T
28REELER (LEERER with R/L switched)
31O(R)LOP (POOL anag)
32MACE (CAME anag)
33ZIT + I
34aSPECt
35lEDGE
38EMU (hidden)