All answers relate to trees, woodworking methods, trades & tools some also include sayings & songs
An extra clues grateful
1. Dogsbody! (6)
16. Misunderstand and waste effort (4,2,3,5,4)
20. Fruit tree from Scottish island (8)
25. March to the centre of tree (5,2,3)
29. Attempt to offer for sale (9)
30. Secure a bargain (6,1,4)