Churchyard Nature Note with Andrew Tompsett

August 2015

Was the Mustard seed a tree?

The mustard seed which Jesus likened to the kingdom of heaven, is thought to be the Black Mustard (Brassica nigra).   It is a common plant of Europe and Mediterranean countries and would have been well-known to the mainly rural agricultural people of Palestine near to Galilee. It was valued as a spice, for the leaves, as a green manure and for the oil which some believed had medicinal properties.

The parable , which appears in the books of Matthew, Mark and Luke says that the mustard seed is the smallest seed which is planted in the garden and the plant, which grows very rapidly, becomes like a tree in which birds may shelter. It could have been attractive to finches of the region?

There are plenty of plants with much smaller seeds but in common parlance of the day the miniscule size was a widely-used comparison. Although growing over two metres high, it is an annual plant which has to grow from seed every year. Having a strong woody stem it could be thought somewhat tree-like in a rather arid landscape.

So far we have no specimen of Black Mustard in our churchyard but this huge plant with spreading branches which are smothered in smallish yellow flowers in mid-summer can readily be seen in places along the A30 and in uncultivated areas especially by the coast. The large framework of branches stands erect from one year to the next even when the plant itself is dead.

Mustard seed is, of course, the source of edible mustard although it is the seed of White Mustard (Brassica alba ) and Brown Mustard (Sinapsis spp.) which are the main ones used nowadays. All are members of the Cruciferae family and related to cabbages, cauliflowers and many other herbs and vegetables. Charlock (Sinapsis arvensis), formerly a common arable weed and the cultivated Oilseed Rape (Brassica napus) which creates bright splashes of yellow in the landscape in the spring are also members of this same family characterised by a four-petalled flower in the form of a cross.

There are some perennial members of this family such as Sea-kale. Although I’ve never seen it, Lundy Kale is a tall perennial found on Lundy Island which has a very stout woody stem. This may be the originator of what was once advertised as Jersey Kale whose tough knobbly stem could form a durable walking stick!