1. Work that is Permitted on Chol HaMoed, 5 Seifim: It is permitted to grind flour for a holiday need, even if one planned to do thi on the holiday. [The same is true for] cutting trees from the ground or making mead, whether it is from dates or barley, for a holiday need. If it is not for a holiday need, it is forbidden. However, one need not minimize production - rather, one can make a lot, and if he makes too much, he makes too much. However, one should not circumvent the law by grinding too much or making too much (mead) intentionally. Alternatively, if one has flour (or old mead) he should not circumvent the law (to make more) and say, "I want from this [new] batch." However, if one has bread, he is permitted to grind [wheat] (for bread), because warm bread is preferrable. (This is also the law for mead - if the new is actually better than the old, it is allowed) (the Magid chapter 7).
2. It is permitted to uproot flax because it can be used to cover foods, to uproot hops because it can be used to make mead needed on the holiday, and to uproot sesame because the dry ones can be eaten immediately.
3. If fruits have ripened a bit such that they can be eaten in a stretch, it is permitted to collect them in order to eat them. If one collected them to eat them, collected too much, and he now worries that they will rot if they are not pickled to remove the moisture, he can pickle them. However, it is forbidden to collect in order to pickle. If there is something that won't be available after the holiday, it is permitted to buy it and pickle it.
4. A man can catch as many fish as he can catch and then salt all of them on the holiday. This is because it is possible to eat them on the holiday by squeezing them by hand many times until they are soft. (It is permitted to catch [fish] in public, because it is clear that it is for the holiday) (Mordechai).
5. For any labor that is done for a holiday need, if one also does it professionally, it must be done in private. How so? Hunters (of animals and birds), grinders, and those who pick grapes to sell in the market should do it in private when done for a holiday need. Rem"a: It is permitted to milk an animal even not to fulfill a holiday need, because it will result in loss otherwise (Trumat Hadeshen chapter 153 and Beit Yosef).