Knotgrass
Paspalum distichum · Aquatic plants
Flowers or seeds · Photo: Augustin Soulard / CC BY
Also called Joint paspalum, Paspalum
How to identify Knotgrass
- Low creeping grass with long runners rooting at the nodes
- Two short, paired spikes at the stem tip like a V
- Short flat leaves
- Forms dense mats on mud
Similar plants
Bermudagrass has 3 to 6 spikes and grows on dry ground.
Growth profile
| Growing season | Starts late in spring with warm soil, grows through summer and flowers July to September. |
|---|---|
| Starts growing | About 60 F soil; full sun |
| Light | Needs full sun |
| Depth | Moist shoreline to about 1 foot of water |
| How it spreads | Runners, rhizomes and seeds |
| Habitat | Muddy pond and reservoir shores, canal banks and ditches at low elevation. |
Why it matters in a lake
Can form mats creeping into shallow water along canals and ponds.
Where it is found
- Idaho: Occasional
- Oregon: Occasional
- Wyoming: Not recorded
Classification
| Kingdom | Plantae |
|---|---|
| Phylum | Tracheophyta |
| Class | Magnoliopsida |
| Order | Poales |
| Family | Poaceae |
| Scientific name | Paspalum distichum |
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Baltic rushNeed a hand?
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