Here's a scenario:

One lands on the Canyon in the Highlands and draws 3 cards.

The first card is the lodestone and is picked up but must ditch an object.

The second card is the Prospector and thus the lodestone is sold.

The third card is another object.

Can one only pick up the object drawn, or can one also pick up the ditched object as the encounter number is 5?

Nope, you may not pick up stuff that you ditched during the same turn.

(base game rules p.9)

But you may ditch things before encountering a space to avoid drawing cards <- kinda weird and why I remember the above.

Thanks.

Thought that was the case, but was looking in the wrong part of the core rulebook.

But you may ditch things before encountering a space to avoid drawing cards <- kinda weird and why I remember the above.

Yeah never did it myself, I can see the advantage eg Sage etc but still never did it.