# Differences Vallisneria, Saggitaria and the thinner Echinodorus/Helanthium leaves?



## Jane in Upton (Aug 10, 2005)

Hi All,

I know I should "know" this, but I recently received some plants labelled as E. tennelus (yes, I know they should now be Helanthium tennelus) and because the leaves show a LOT of horizontal "striations", or markings within the body of the leaf, rather than a mid-vein, I'm now questioning whether these are even Echinodorus at all. They are all young plants without offsets yet.

I know quite awhile back, I found some information on how to differentiate Echinodorus, Vallisneria and Saggitaria. In particular there was information about whether runners which developed AFTER a plant was planted and established (i.e., ones which grew in situ) traveled above or below the substrate surface, but I can't find my notes on which was which! Sheesh - I'm terribly rusty on plant recognition now. Even C. Kasselmann's book says there is often confusion between V. 'nana' and E. angustifolia.

Do I have these differentiating features correct? Could you ADD TO, or correct what I have here? Thanks!

Echinodorus / Helanthium; 
Have a conspicuous central vein running the length of the leaf. 
Runners generally travel (? above/below ?) surface of substrate.

Vallisneria;
Have horizontal structural markings within the leaf, apparent when light is shone through the leaf.
Runners generally travel (? above/below ?) surface of substrate. 
Tips of leaves show some small teeth (magnifying glass required). Leaf tip more acute than in Sags.

Saggitaria;
Roots are generally coarser or thicker than Vallisneria roots.
Tips of leaves do NOT have any tiny teeth, and are often very blunt, or obtuse than in Vals.
Runners generally travel (? above/below ?) surface of substrate.

Thanks VERY much!
-Jane


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## miremonster (Mar 26, 2006)

According to Cook, Aquatic Plant Book, within the family Hydrocharitaceae only Hydrocharis and Limnobium have branched roots, all other, incl. Vallisneria, have unbranched roots.
Alismataceae as Helanthium and Sagittaria _may_ have branched roots.

Helanthium: runners generally above ground (here they are modified inflorescences => pseudostolons). Sagittaria: runners generally below ground. Tubers at the end of the runners may occur. Vallisneria: I'm not sure.

I've noticed that Val leaves are slimy when crushed. 
Often the innermost pair of lateral nerves reach the midrib below the leaf tip (similar to Potamogeton). In Sagittaria they run to the leaf tip or reach the leaf margin below the tip.


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## Jane in Upton (Aug 10, 2005)

Thanks MireMonster!

That is interesting about the branched roots - I hadn't ever come across that info, or even thought about it as a characteristic!

And thank you for clarifying which runners are below ground, and which above.

I appreciate your input!
-Jane


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## asukawashere (Mar 11, 2009)

FWIW, my vals pretty much exclusively display above-ground runners (and trust me, I have _plenty_ of Vallisneria to compare. They and my liquid rock water get along like a house on fire. ').


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## Jane in Upton (Aug 10, 2005)

Thanks - 
OK, so the vals are above substrate level.

And yeah, I used to have very hard water, and the vals loved it. 

-Jane


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## Newt (Apr 1, 2004)

I used to keep two varieties of Vals and they do prefer harder water. Flourish Excel will melt them in soft water but not hard and since I have VERY soft water I now keep Cyprus helferi.


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