Equisetum arvense 問荊、杉菜

Common name: Field Horsetail
Scientific name: Equisetum arvense 問荊、杉菜
Genus: Equisetum 木賊屬
Family: Equisetaceae 木賊科, horsetail family

Origin: native

Date: 4th June

[066] Deciduous erect or prostrate perennial, can reach up to 80 cm.

[080] Fully branched shoots.

[074] The top of the individual. 

[076] Branching.

[089] Lowest branch segments (blue arrow) as long as,
or longer than the stem sheath (red rectangle).

[070] Found a node with lowest branch segment as long as the stem sheath.

[069] Stem sheath teeth with black tips, but without pale margins (lacks membranous margins).

(vs stem sheath teeth black with conspicuous pale border (membranous margins) in marsh horsetail, Equisetum palustre 犬問荊)

[073] Internode. Note the green, spreading branch teeth.

[078] Stem smooth, with 8-20 ridges. (vs 5-9 ridges in marsh horsetail, Equisetum palustre 犬問荊)

[076_1] Branches 4-angled. Green branch teeth with a tiny black tip. (vs dark-tipped teeth on side branches in   marsh horsetail, Equisetum palustre 犬問荊)

[076_2] Totally green branch teeth.

[075_1] Branches sub-branched.

[075_2] Enlarged photo above to show the sub-branching.

[082_1] Stem cross-section showing 10 ridges (8-20 ridges).

Equisetum palustre 犬問荊

Common name: Marsh Horsetail
Scientific name: Equisetum palustre 犬問荊
Genus: Equisetum 木賊屬
Family: Equisetaceae 木賊科, horsetail family

Origin: native

Date: 5th July & 7th July

[291] Deciduous erect perennial, can reach up to 50 cm. Stem regularly branched throughout its length. Branches upcurved. (Fully branched, but also unbranched or partially branched.) Cones are borne on photosynthetic shoots (as shown above).

[281_1] Probably a vegetative shoot (It emerge a bit later than the photosynthetic shoot.)

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The photos below are all photosynthetic shoots:

[277] Showing the internode and the branches at the node.

[281] Stem sheath teeth black with conspicuous pale border (membranous margins).  Stem smooth, with 5-9 ridges. (vs stem smooth, with 8-20 ridges, stem sheath teeth black but without membranous margins in  field horsetail, Equisetum arvense 問荊、杉菜) 

[077_1] (taken on another location)

Note the lowest branch segments (blue arrow) are shorter than the stem sheaths (red rectangle). (vs the lowest branch segments are longer than the stem sheath in field horsetail, Equisetum arvense 問荊、杉菜) 

[077_2] (taken on another location)

Fully branched shoots have dark-tipped teeth on side branches.

(vs green, spreading branch teeth in field horsetail, Equisetum arvense 問荊、杉菜) 

[275_1] Branches at upper stem.

[275_2] Branches a bit below.

[290] Branches further below, with longer branches.

[283_1] Cones are borne on photosynthetic shoots.

[275_3]

[273_1] Cones showing the hexagonal sporangiophores.

[287_2] Another mature cone.

[287_1] Sporangiophores are split apart from each other, and sporangia underside them could now be seen.

[059_1] (taken on another location)

Stem cross-section, with clearly 6 ridges (5-9 ridges) in this individual.

Equisetum telmateia 巨問荊

Common name: Great Horsetail
Scientific name: Equisetum telmateia 巨問荊
Genus: Equisetum 木賊屬
Family: Equisetaceae 木賊科, horsetail family

Origin: native

Date: 26th April (cones on non-photosynthetic shoots) & 27th June (vegetative shoots) on different locations.

[334_1] Fertile stems (non-photosynthetic shoots) separate in spring, can grow up to 25 cm.

[349] Newly fertile stem shoot with cone at the top already.

[349_1] Young hexagonal sporangiophore and green sporangia underside.

[340] Cone 4-8 cm, are borne on non-photosynthetic shoots.

[350] Another fertile shoot with bending.

[336] Young cone, with sporangia mature started from the bottom.

[338] An older cone.

[339] Older sporangiophore were found near the base of the cone.

[347]

The enlarged photo of the bottom end of the strobilus (cone) 孢子葉穗, 孢子葉球 showing the thick central strobilus axis (Sa) (cone axis). There is a ring-like outgrowth present below the strobilus, which is called annulus (As). Some thought that it is the uppermost whorl of sterile leaves while others thought that is is the lowermost sterile sporangiophore.

[336_2] Younger sporangiophore are found at the top of the cone.

[336_1] Sporangiophore found at the middle of the cone.

[336_3]

[339_2] Enlarged photo showing the structure of the sporangiophore. Each sporangiophore has a stalk (St) to attach to the thick central asix known as strobilus axis (cone axis). The free end of the sporangiophore is a hezagonal peltate disc (Pd). Many sporangia (singular - sporangium, Sg) are attached on the undersurface of the Pd.

[339_1] Side view of an sporangiophore 孢子囊托, 孢(子)囊柄 (outlined in red).

[337_1] Fly is attracted to the sporangium.

[347_1] The oldest sporangiophores are found near the base of the cone.

[341] Internode and stem sheath of the fertile shoot.

[342_cropped] Swollen stem sheath of the fertile shoot, with dark, fine-pointed teeth.

[346] Dying out fertile stem (probably last year stem).

[352] Vegetative shoot? starting emerging from the soil.

[352_1] Stem sheath of the young vegetative shoot?

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The following photos were taken on 27th Jun on another location. All are vegetative shoots now.

[094] A robust deciduous perennial, can grow up to 2 m. This is the largest British horsetail.

[081] Stem about 1 cm diameter at base.

[062] Richly branched to top of stem.

[066]

[066_1] Stem internodes ivory white until autumn, with 20-40 fine ridges (the ridges are very unclear indeed).

[066_2] Stem sheath with 20-30 teeth. Teeth dark, fine-pointed, to 10 mm.

[067] Branches at the node with stem sheath. Note the branch segments have slightly black, tipped teeth.

[090_1] Underside of the node showing the point of branching.

[071] Side branches.

[071] slightly black, tipped teeth of the side branches. Note the branches are angular.

[096_1] The tip of the side branch, with tipped teeth.

[073] The uppermost of the stem showing the gradual change of the stem sheaths.

[077] The uppermost of the stem of another individual showing the gradual change of the stem sheaths.

[087] Stem cross-section.