Division of labors

The horsetails outside my bedroom window are small and delicate. Along the highway north, though, they're tall and fat, covered with their tiny "flowers" with stubby petals. A different species: at home, they're field horsetails, Equisetum arvense; in the wild, they're giant horsetails, Equisetum telmateia, var. braunii.

Horsetails do not have flowers, nor do they make seeds; rather, they produce spores in little buttons, like the ferns. In the ferns, these "buttons" are on the underside of the leaves. The horsetails grow a fertile head dedicated entirely to spore production. (Called a strobilus.)

Horsetail patch. Sterile stems, spore producing stems.

The spore-producing stems show up first. As the spores ripen, the sterile stems start to grow. For now, they're about 45 cm. tall; they will grow to a couple of metres tall by mid-summer.

The fertile stems, though they have a bit of green in the stem itself, do not "feed"; they're not photosynthetic. Once the spores ripen, these stems will die. The new, green, bristly stalks will do the work of transforming sunlight into food.

Fertile stem, with sporangiophores. Not really flowers.

On this stem, the only leaves are the brown tips of the sheaths that circle the stem at intervals.

Stem with sporangiophores arranged in spiral rows..Click to zoom in and see them.

And here are the "flowers": stubby tacks with many miniature, round "petals".

A young sterile stem. The branches will spread out horizontally as the stalk grows.

This species was the most preferred Equisetum species of coastal native peoples as an important springtime vegetable. The young fertile and vegetative shoots were picked, de-sheathed and eaten raw. However, this genus has been known to be poisonous to livestock and humans if eaten in large quantities. Some native peoples also picked the tops of these plants, boiled them, and drank a glassful of the liquid to cure a urinary ailment. E. telmateia was one of the many Equisetum species used as medicine to treat burns; the stems were burned and the ashes applied to the wound. The silicon dioxide crystals make Equisetum species great scouring tools. Native peoples used them extensively for smoothing and polishing wood and soapstone. In fact, modern-day hunters and outdoors people still use them as scouring utensils for cleaning pots and pans. (Joseph Maser, Indiana U.)

I can't imagine eating these! They're scratchy, even to hold.

~~~~~~~~~~~~~~~~~~~~~~~~~

Hay varias especies de cola de caballo (Equisetum sp.). Junto a mi casa, son pequeñas; son Equisetum arvense, la cola de caballo campestre. Al lado de la carretera hacia el norte, son grandes, gordas, fuertes: Equisetum telmateia, la cola de caballo gigante.

La cola de caballo no produce flores. Como los helechos, se propagan por medio de esporas que se hallan en "botones"; en los helechos estos se encuentran en la parte inferior de la hoja. La cola de caballo lleva una cabeza (llamada estrobilo) llena de estos esporangióforos.

Hay dos tipos de tallos: primero aparecen los tallos fértiles, con sus esporangióforos. Estos, aunque tienen un poco de verde, no llevan a cabo el fotosíntesis; su única función es producir las esporas. Una vez maduras, el tallo se muere.

Luego surgen los tallos verdes, no fértiles, que trabajan produciendo los azúcares que necesita la planta.

(División de labores. ¡Sin quejas!)

Partes de la cola de caballo: las hojas son las puntas cafés de las envolturas que se ven a lo largo del tallo. Las "agujas" verdes no son hojas: son ramas. Los "botones" o "tachuelas" (esporangióforos) no son flores, y los "pétalos" no son pétalos. Aquí se producen las esporas.

La última foto es un tallo no fértil, todavía sin abrir sus ramas.

(De la cita:) Los nativos comían estas plantas en la primavera; se pelaban los tallos y se comían crudos. Sin embargo, este género es nocivo, comido en grandes cantidades. Algunos nativos hervían las puntas y se tomaban el líquido para curarse de males del tracto urinario. También se usaba para curar quemaduras.

Debido a los cristales de dióxido de silica, se usan estas plantas como papel de lija o trapos de fregar, tanto para pulir madera y esteatita, como para lavar trastes.

¡No me imagino como se come esta planta! Se sienten bien rasposas al primer tacto.