If the orchids on your friends trees are native Florida orchids then he can't transport them or sell them without a permit from the state of Florida. Here's the actual paragraph in the Florida law.

(d) Any person transporting for the purpose of sale, selling, or offering for sale any plant listed on the Regulated Plant Index, except for those plants listed as threatened, which is harvested from the person's own property must have a permit from the department in his or her immediate possession when engaged in any of the described activities.

Lots of good advice above.

Based on the number of "grey areas" you could run into with the law, your friend probably needs:

(1) the advice of a natural resource attorney licensed in Florida;
(2) a botanist that can positively ID the plants on his(her) property.

Then, it appears that a permit may be needed, if the plant is regulated. All for some plants that may or may not survive being dug up and transplanted.

You have to wonder if the effort and expense would be worth it?

BTW, which orchids are growing there? Some are not commercially viable, because of its size, no significant market, etc, etc

You definitely need to get clarification, but that paragraph does not prohibit transportation, it prohibits transportation for sale. It is clearly within the meaning of that paragraph to transport the covered species for purposes other than sale., such as giving them away. But the final effect of any law comes down to who interprets and enforces it, so a talk with the proper authorities would be wise.