1: Field of fruit trees resulting in poor Chardonnay (7)
4: To me, his convertible is most comfortable (7)
8: Witticism provided theme (5)
10: Name successor in speech? (7)
11: Orchestra I'm reorganizing for certain conductor (11)
12: Fish spawn upstream in little orifices (3)
15: Enjoy a mud pie and trade it freely (3,4)
17: One who tempts peril grabbing leopard's head (7)
18: Short line in letter back-fires (5)
19: Top card? Excellent! (3)
20: Exchange concealed proprietary knowledge (5,6)
22: Nanny, for example, entertained by young pig (3-4)
24: Hangs ten vassals at hearing (5)
25: What models do when embraced by former Democrat leader - all is revealed (7)
26: Legendary rich guy gets called, then folds (7)