Up
Cordyline stem
grass leaf
ragweed stem
Clover stem
Parsnip stem
Grape bark
Buttercup root
Catclaw root
Catclaw, mag
Corn root
Sieve tube ls
sieve plate, side
Sieve plate, face
Sieve areas
Pine bark
Cosmos stem
Cucumber sieve plate
Sieve plate, mag
Companion cells
Fern stem
P-protein plug
Collapsed phloem
Collapsed phloem
Collapsed, grape

Fig. 8.2-4b. Low magnification of pine bark. This lower magnification view shows that this region of pine secondary phloem consists almost exclusively of sieve cells (every cell with a sieve area on it is a sieve cell). The density of sieve areas and sieve pits is high – the many cells of this conducting pathway are strongly interconnected.