Reddit reviews The Tree Climber's Companion: A Reference And Training Manual For Professional Tree Climbers

There are courses you could go on if your club can raise the money. Here's one in the Netherlands although the web page is in some weird foreign language :-þ There's one across the Channel in Cornwall and there are some in Denmark too. There's a lot more now than there were 10 years ago, have a google around.

An alternative is buying some basic equipment and teaching yourself from a book. I have The Tree Climber's Handbook and it outlines all the basic techniques and knots. If nothing else you could just buy this book and study it. That's what I did.

In theory it's possible to climb using just a single rope and nothing else by making a Swiss rope harness, but if you want a safe and easy start you'll need:

• Climbing saddle. This is different to a rock climbing harness. It is more heavy-duty. Rock climbing harnesses are only to catch you if you fall. Tree climbing saddles hold you all the time so have to be more padded and comfortable.
  
• A long (20m or more), 13mm thick nylon arborist rope. Again different to a rock climbing rope; slightly thicker so you can grip it with your hands and less bouncy.
  
• A throw line and weight to help get the rope up in the tree
  
• A cambium saver / false crotch to protect the branch's bark, and a retrieval ball
  
• A descender (e.g. figure of 8) device
  
• At least two strong carabiners
  
• Helmet
  
• Boots, preferably with rubberised side-grips to make it easier to climb the rope
  
  This is enough to get you into the tree and into a hammock, but you'll also want lanyards and more carabiners if you're going to move about in the tree canopy. Honey Brothers sell all of this but it's quite pricey so this isn't necessarily the cheaper option versus attending a course! And it's certainly not as safe.
  
  A third option is to stay below 5 metres above a nice soft leafy forest floor and just climb with no equipment at all :-D

Here is the mobile version of your link

The Tree Climber's Companion: A Reference And Training Manual For Professional Tree Climbers https://www.amazon.com/dp/0615112900/ref=cm_sw_r_cp_apa_i_uBE6Cb22WTZND

Ditto in the ISA. order the arborist study guide. Order this book... The Tree Climber's Companion: A Reference And Training Manual For Professional Tree Climbers https://www.amazon.com/dp/0615112900/ref=cm_sw_r_cp_api_fPgnxb0SJSK4V

Also lots of tree climbing/arborist groups on the Facebook. Instagram is filled with arborists sharing knowledge as well. Reddit is kind of lacking in the arborist world. Hard to Reddit in trees.