This picture is the japanese black pine. Should I separate each of tree root or use the plant cuttings technique to plant them.
Before giving advice it would be helpful to know your location. Also are the buds on top opening or have they already extended? The needles are hiding the top portion.
On closer look, i see pretty woody stems. I would recommend that you separate each tree and cut a bit of the tap root off, leaving several side shoots for each cutting.
Others may choose a different route, but i think that is the safest. There is plenty of time to work on developing nebari.
Best in Bonsai
Thank you for your recommendation. I plant the tree in Thailand.