Seasonal Wild Flowers

Latin name

Equisetum telmateia

Family

Equisetaceae

Flowering season

March to May for fertile stems

April to November for vegetative stems

English distribution

It is found throughout the country except for parts

of the Southwest, the East and the North

See the BSBI distribution map for Great Horsetail

Habitat

It grows in open and damp grassland, fens, open

woodland, along seepage and spring lines and

on eroding cliffs. It is also found by streams, rivers,

canals, roads, tracks and railways

Description

Great Horsetail is a native, patch-forming, rhizomatous and

tuberous herb growing up to 2m.

Fertile stems are cream and non-photosynthetic and grow

up to 45cm. They have prominent sheaths, which are white

at the base and brown at the top with up to 20 pointed

brown teeth.

Spores are produced on an apical strobilus (cone) up

to 10cm.

Each cone has numerous hexagonal scales which

produce up to 20 spore cases on their undersides.

The spores are dispersed and germinate to form a

small, green, independent prothallus on which the

male and female gametes are formed.

The horsetail we see is the sporophyte which is the

result of the fusion of the male and female gametes

from the prothallus.

After spore dispersal, the fertile stems die.

Sterile, vegetative stems appear towards the end of

the life of the fertile stems.

They are green, photosynthetic and up to 2m.

The stems are white and have whorls of up to 40

green branches.

The banches are up to 20cm, up to 2mm in diameter.

Great Horsetail can form extensive patchedsas a

result of aerial growth from the rhizomes.

The rhizomes can grow to depths of several metres

 in clay soils.

Great Horsetail is not a wild flower or even a flower,

for that matter.

However, it is a striking, primative, wild, spring time

plant which demands attention and identification.