I'm assuming you mean the rings around the planetsinstead of the plants. They are made of dust, rock, and occasionally ice.
Yes they do
The rings are 50m long, made up of 20000 plants
The four inner [terrestrial] planets: Mercury, Venus, Earth and Mars.
Do your homework and you would know.
The xylem.
C4 plants have concentric rings of mesophyll cells around vascular bundle sheath in the leaves.
what causes tree rings to form each year
Trees show growth rings on the cross-section of their trunks.
They are all gaseous planets with rings systems and many moons.
They have RINGS that surround the Planet, and are 'Gas Giants' without a solid surface.
1. Both gas giants 2. they are Jovian planets 3. Both have rings 4. Are both outer plants