In the text with respect to Orchard it says the cost after 4 years equals the income produced. Therefore it implies the income should have no net value in years 5-9 but the notes below and on page 96 say the maintenance cost is only in years 1-4 then the orchard makes £1 for years 5-9 ( etc). So my question is does the maintenance cost continue after year 4 for an orchard ?

A fishery is also confusing, does the fishery itself generate 3+2 per weir & the weir generate another 2 ( thus when you have one weir and one fishery you get 7) or is the weir income included as the "+2" in the fishery description?

Alas, I don't own BotE, so I am unable to check wording on that for you.

However, in Book of the Manor, Orchard produces £0 during the first 4 years and then 1d2 for 5-10, and 1d3+1 after that. With the maintenance cost of £1, and the way that BotE tries to get rid of the rolling, my educated guess is that:
Orchard (BotE): -£1 (maintenance) for the first 4 years, +£1 (£1d2-£1 maintenance = 0-1, averages 0.5 and rounds up to 1) 5-10 years after building, +£2 (1d3+1-1 maintenance = averages to 2) after that.
Granted, it could round down instead to 0, but generally in Pendragon, you round halves up.

As for the Fishery, if the income is really typed as "£3+£2 per weir", then that is exactly how I would read it: the Fishery itself produces £3 and each attached weir adds £2 to the total. No double-dipping for the weirs.

Morien nailed it