Vexed by Vetches

The Pea Family (Fabaceae) can be a little vexing at times – with this group the small details are often what separates one species from another fairly similar looking species. Fortunately the two vetches that I’ve found so far at the Courtenay Airpark are fairly distinctive and easy to identify. Vetches can be differentiated from most of the other members of Fabaceae by the fact that the terminal leaflet of each set of leaves is actually a tendril. Keep in mind that both vetches (Vicia sp.) and peavines (Lathyrus sp.) have tendrils instead of a terminal leaf. The difference between these two is the arrangement of hairs on the style. Vetches have hairs that surround the style like a bottlebrush, while peavines have hairs on one side of the tip of the style like a toothbrush.

Common Vetch (Vicia sativa) Flowers
The flowers of Common Vetch (Vicia sativa) are on short stalks located in the leaf axils.

One of the vetches is Common Vetch (Vicia sativa). It has fairly large (to 3 cm) purple pea-like flowers that grow on very short stalks in the leaf axils. The leaves are pinnately compound with 8 to 16 leaflets ending with well-developed tendrils. Each leaflet is squared to notched and has a pointed tip. Common Vetch is common along roadsides, clearings and waste places and is introduced from Eurasia.

Common Vetch (Vicia sativa) Leaflets
The leaflets of Common Vetch (Vicia sativa) are square or notched with a pointed tip.

The second vetch was one that I’ve only recently noticed while looking closely at grass during a workshop at the Airpark (I’ll save that for another post!). The appropriately named Tiny Vetch (V. hirsuta) has very small white flowers (about 4 mm long) at the end of a short stalk that emerges from the leaf axils.

Tiny Vetch (Vicia hirsuta)
The tiny white flowers of Tiny Vetch (Vicia hirsuta) are around 4mm in length.

Tiny Vetch has pinnately compound leaves with 12 to 18 leaflets ending with well-developed tendrils. Each leaflet is 0.5 – 2 cm long and squared off and notched at the tip. It favours similar habitat to Common Vetch and is introduced from Eurasia.

Tiny Vetch (Vicia hirsuta)
Note the well-developed tendrils at the end of the pinnately compound leaf of Tiny Vetch (Vicia hirsuta).

Once again, I’ve discovered that introduced species can be interesting to take a second look at. These two peas are ones that I’m now more familiar with and will keep an eye on while on my weekly nature walks.