In the Chaitanya-Charitamrita, Lord Chaitanya and His movement are compared to the tree of devotion, the Bhakti-Vriksha:
The Lord brought the desire tree of devotional service to this earth and became its gardener. He sowed the seed and sprinkled upon it the water of His will. By His inconceivable powers, Sri Chaitanya Mahaprabhu Himself became the gardener, the trunk and the branches of the tree of devotional service simultaneously. From the trunk grew many branches and above them innumerable others. Thus the branches of the Chaitanya tree formed a cluster or society, with great branches covering all the universe – Chaitanya-Charitamrita Adi, 9.18.
Lord Chaitanya would go from village to village, and everywhere He went, each person he preached, would branch out and make five more families Krishna conscious. Each of those families would make five more. The Bhakti-Vriksha programme uses a similar dynamic, with small groups that multiply by each member bringing new people to Krishna Consciousness. Just as in a tree, a branch of a certain thickness divides in two, so the Bhakti-Vriksha group divides into two smaller groups at a certain point.
Srila Prabhupada writes in his summary of Adi-lila, Chapter Nine:
“It is figuratively described that both the tree itself and the trunk of the tree are Sri Chaitanya Mahaprabhu… The tree surrounds the entire world, and the flowers of the tree are to be distributed to everyone. In this way the tree of Lord Chaitanya Mahaprabhu intoxicates the entire world.”
Srila Prabhupada also says:
“Our International Society for Krishna Consciousness is one of the branches of the Chaitanya tree. -Chaitanya-Charitamrita, Adi-lila 9.18
Every small group in ISKCON’s congregation is therefore a branch of the branch, stemming from the Bhakti-Vriksha, the tree of bhakti of Lord Chaitanya. The Bhakti-Vriksha group is a type of Nama hatta group especially geared toward branching out. Just like a tree, a branch of a certain thickness branches off into two. This branching process keeps going until the tree has thousands and thousands of twigs all connected to the main root. Lord Chaitanya is the original root, and even one single branch from the tree can grow and form thousands of sub branches, small twigs, leaves and so on.
For those aspiring to make steady spiritual progress through proper understanding of scriptures and to have the company of like minded people, this Bhakthi Vriksha program is very ideal. There are no pre-qualifications to be a part of such a group. Everybody is most welcome to join.