I agree with
@jyoutz . Having a choker or two will come in handy if you are doing much of this work - either skidding trees or freeing ones that are hung up.
You can use either a cable choker as he showed or a chain choker. I don't want to get into the debate of which is "better". It's mostly a matter of personal preference (though the size of the tree can come in to play as well). In my area, almost everyone uses chain chokers, in other parts of the country cable predominates. This link is just an example of a chain choker (I typically buy mine locally):
https://www.amazon.com/Winch-Choker-Chain-Forestry-Logging/dp/B08BZT2ZD4/
In our areas, some tractor dealers who also supply loggers will have these in stock. The key is the special slip hook, which captures the chain much better than a typical hardware store slip hook. The pin on the other end is handy for threading the chain under a log on the ground. For the size trees shown in your picture (and even a good bit larger) 5/16" grade 70 chain should be fine. Some people prefer 3/8" chain. It's stronger but significantly heavier. (I have both, but use the 5/16" most of the time.
You'll need something on the end of whatever you are using to pull with to grab the end of the choker. A grab hook works, but there are other logging-specific devices which are less likely to come unattached as you are dragging through the woods.
If you are doing a lot of this sort of work, a 3 Pt hitch logging winch for your tractor comes in handy. It can be hard to justify the cost if you are not doing a lot of this, but once you own one, you'll wonder how you ever got along working in the woods without one.