Sorrel and Dock

These red spikes are two related plants, sorrel on the left and dock on the right.

     

sorrel                                            dock

Really there are several sorrels and several docks but I just know that if they're small and red and the leaves have little hooky bits near the stalk, like a spear head, they are sorrels. 

Sheep's sorrel leaf

And if they are big, bold flowers, not always tinged with red, and with big leaves, they are docks.

 

Dock leaves