Bushcraft is a skill set, and along with those skills you would need certain tools, materials, and gear, but bush craft is primarily based on knowledge and not on gear or equipment. There is not a kit, if you will that has “Bushcraft Kit” stamped on it.
Bushcraft requires a certain skill set that can take years to master. Survival until rescued requires some skills, but to survive most people would have to rely heavily on materials, gear, and certain other supplies that are in their survival kits.
There is a lot of emphasis placed on survival kits, and the reason being is that people who are not trained in bushcraft need gear. They need a so-called survival kit. People that lack training, or ones that have training, but have not applied their training and knowledge will need a survival kit to survive if they become lost or stranded. Simply put, the less you know, the more you need.
An emergency can be a desperate race against time. If you become lost or stranded you would assume someone would at some point mount a search for you, typically within 72-hours. Therefore, to survive the three days or longer, you would need emergency shelter, rations, water, fire starting materials, and medical supplies.
You need enough to sustain you until rescued or until you can self rescue. Your goal is to sustain life until rescued, and to stay alive you need supplies and gear.
Bushcraft skills develop over time. When someone decides to go off grid, for example, he or she did not wander into the woods and become lost, and then start yearning for the good life back in the suburbs. If you set out with the intentions of never coming back you would assumedly have the skills needed and would not have to rely on a kit that can only sustain you for a short duration.
People that want to live off grid realize they need not only to survive but also to thrive in the wilderness environment for virtually forever, and this takes skill and an extensive knowledge base and takes doing it day after day.
The learning process never stops, and the daily routine is training for tomorrow. They are not looking for rescuers. They are not clinging to their last few ounces of water, or nibbling on the few crumbs left over from a protein bar.
To Answer the Question Posed In the Title
You need some bushcraft training regardless of how you ended up in the wilderness. However, if you do not intend to give up on suburbia then you do not need as much knowledge as say someone that decides he or she will never leave the woods. Mick Dodge comes to mind.
For Those That Like the Occasional Excursion into the Woods
You will need to know how to create a fire in virtually any environment. You must know how to make a temporary shelter, and know how to purify a surface water source. Will the occasional hiker, camper, or hunter need to know how to preserve fish and game and then tan the hides to survive several days in the wilds, what do you think.
To survive and then to thrive in a wilderness environment you would need extensive knowledge of what plants are edible and ones that can be used for medicinal purposes for example. Survival shows and even survival manuals focus on foraging for edibles, and for those that do not have extensive knowledge this can be dangerous. For those that find themselves unintentionally lost, the short-term nutritional value you would get from the plants or berries is not worth the risk of illness or death.
For those that plan to bug-out and survive in the wilds indefinitely, you will need more than a survival kit. You will need extensive bushcraft training. You will need to know among other things, how to butcher wild game, preserve the meats, tan the hides, and know how to use the bone and sinew.
You will need to know what plants can be used to treat stomach ailments, know how to make aspirin from willow, and know what plants that can be used for a poultice to draw out infections. Every day you will realize how little you really know, but you can learn as you go to some extent. Without a solid knowledge base however, you probably will not live long enough to learn anything new.
Master the Skill Sets That You Will Need to Survive 72-hours In the Wilds
1.) Practice making a shelter. Just because you have a tarp or poncho with you does not mean you know how to fashion it so it keeps you dry and protected from the wind. Learn how to make a debris shelter as well.
2.) Know as many ways as possible to start a fire in any environment, but keep it simple. Do not wander out and get lost and then think you can find an ice chip or pee in a Ziploc bag and fire will magically appear. First, never wander anywhere in the wilds without your kit, and make sure the fire starting materials you have are proven methods. Once you are lost is not the time to experiment with something you saw on the Internet.
3.) Know what you need to carry to purify water. No fancy tricks or potions needed, water purification is straight forward. Do not conjure up some elaborate method again keep it simple. Purification tablets and/or the means in which to boil water are easy to carry and are fool proof for the most part.
4.) Know how to signal for help.
5.) Know basic first aid.
If you cannot master these five things then you will have a very miserable time if you do find yourself lost or stranded, and remember the less you know the more you need to carry.
Know enough to survive long enough to learn more. No one can possibly know it all, but if you do not know the basics then your survival is questionable from the very start.