This one here is about 4-5 feet tall they are about 1/8" to 1/4" from top to bottom in Northern Indiana
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what part of the world are you in? – kevinsky♦ Jul 15 '19 at 23:19
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Northern Indiana – Art Jul 15 '19 at 23:51
This is likely a gall produced by a fly on a species of goldenrod. When the fly lays the eggs in the tip of the plant a hormone is produced that interferes with the normal development of the plant cells, forming that bulge which will protect the developing eggs and larvae. See for example this discussion.
answered Jul 16 '19 at 0:16
