test
node1
BFO:0000003
occurrent
node1->node1
node6
BFO:0000015
process
node1->node6
node2
GO:0008150
biological_process
node3
GO:0040007
growth
node2->node3
node4
GO:0080190
lateral growth
node3->node4
node5
GO:0080117
secondary growth
node4->node5
node6->node2
node7
BFO:0000001
entity
node7->node1