Not to be semantically confused with : Sheep-laurel or Sheep's-bit [plants with similar names]

Easily mistaken for : many other Docks, which belong to the same Rumex Genus, until it is closely inspected.

Although many docks hybridize with each other, Sheep's Sorrel does not participate.

Two sub-species exist, all under the same common name, Sheep's Sorrel:

• Sheep's Sorrel (Rumex acetosella subsp. acetosella) where a loose cover around the fruits (achenes) is easily rubbed off between finger and thumb. A variety of this sub-species exists calledRumex acetosella subsp. acetosella var. tenuifolius which grows in sand, is smaller and has only linear leaves.
• Sheep's Sorrel (Rumex acetosella subsp. pyrenaicus) where the cover around the fruits (achenes) is NOT able to be rubbed off between finger and thumb.

Called Sheep's Sorrel because it typically grows where sheep roam. It has a tough rhizome by which means it spreads, sometimes un-controllably. Since it cannot tolarate lime, infestations of Sheep's Sorrel on arable land are indicative of it needing lime.

It inhabits grassy places with some bare soil both in lowlands and on acidic heathland hills, but not usually at the summit of high mountains.

Like other Docks and Sorrels Common Sorrel has an acid taste due to the presence of poisonous Oxalic Acid, specifically the calcium salt, Calcium Oxalate, which forms extremely tiny needle-shaped and extremely sharp crystals called raphides, which, when consumed, cause mechanical damage to cells puncturing the membranes and allowing things out and foreign substances in. That said, like other Sorrels, the leaves are still used in salads (not many leaves are used in salads). It is only fatal when great quantities are consumed.

It also contains Tartaric Acid, which also imparts a tart taste to the leaves. An anthraquinone called Chrysophanol (aka Chrysophanic Acid) (1,8- dihydroxy-3-methyl-9,10-anthracenedione) is present and can be extracted as a yellow dye.