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- Cinna arundinacea
Cinna arundinacea — sweet wood-reed
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Facts
Sweet wood-reed is a tall and attractive grass, and is a good substitute for the invasive Japanese stilt-grass (Microstegium vimineum). The Iroquois used this species as a treatment for diabetes.
Habitat
Floodplain (river or stream floodplains), forests, marshes, shores of rivers or lakes, swamps, wetland margins (edges of wetlands)
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- 
                                
                                    - terrestrial
- wetlands
 
- New England state
- 
                                
                                    - Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
 
- Leaf blade width
- 3–19 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 3.5–7.5 mm
- Glume relative length
- one or both glumes are as long or longer than all of the florets
- Awn on glume
- 
                                
                                    - the glume has an awn
- the glume has no awn
 
- One or more florets
- there is one floret per spikelet
- Lemma awn length
- 0.2–1.5 mm
- Leaf sheath hair type
- there are no hairs on the surface of the leaf sheath
- Leaf ligule length
- 2–10 mm
- Anther length
- 0.8–1.8 mm
- 
                        Flowers- Anther length
- 0.8–1.8 mm
 - Anther number
- 1
 - Awn on glume
- 
                                
                                    - the glume has an awn
- the glume has no awn
 
 - Bristles below spikelets
- no
 - Floret lower bract texture
- the lemma is thin and flexible
 - Floret number
- 1
 - Floret types within spikelet
- all the florets within a spikelet are similar
 - Glume awn length
- 0 mm
 - Glume keel
- the glume keels are rough or hairy
 - Glume relative length
- one or both glumes are as long or longer than all of the florets
 - Glume shape
- the glume is V-shaped in cross-section
 - Glume veins
- 
                                
                                    - 1
- 3
 
 - Glumes per spikelet
- 2
 - Inflorescence arrangement
- the spikelets are uniform
 - Inflorescence axis orientation
- the inflorescence axis is straight
 - Inflorescence branch roughness
- the inflorescence branches are smooth or only slightly rough
 - Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
 - Inflorescence crowding
- the panicle is somewhat to very spread out, with clearly-evident branches
 - Inflorescence length
- 65–550 mm
 - Inflorescence length to width ratio
- 2.2–8.3
 - Inflorescence type (general)
- the spikelets are borne on stalks or on branches
 - Inflorescence type (specific)
- the inflorescence is branched, and the branches do NOT both grow from the same side of the plant AND look like spikes
 - Inflorescence width
- 30–120 mm
 - Inforescence position
- the spikelets are mainly carried at the end of the stem
 - Lemma awn base
- the awn is attached at the upper half of the lemma
 - Lemma awn coiled
- the lemma awn is straight or twisted, but not coiled one half turn
 - Lemma awn length
- 0.2–1.5 mm
 - Lemma awn number
- 
                                
                                    - the lemma has no awn
- the lemma has one awn on it
 
 - Lemma awn orientation
- the awn of the lemma is straight
 - Lemma base hair length
- 0 mm
 - Lemma base hairs
- the lemma is hairless or feels just a tiny bit rough at the base
 - Lemma cross-section
- the lemma is V-shaped if you cut across the midpoint
 - Lemma hairs
- the lemma is hairless between the veins
 - Lemma surface
- the surface of the lemma is relatively smooth (not counting any longitudinal veins or hairs)
 - Lemma tip
- the lemma tip is split into two or more points
 - Lemma tip shape
- the lemma tip tapers to a narrow point (it may or may not also have an awn or teeth at the tip)
 - Lemma vein number
- 
                                
                                    - 3
- 5
 
 - Lower glume length
- 2.7–6.1 mm
 - Lower glume relative length
- the lower glume is nearly as long, or as long as, the upper glume
 - One or more florets
- there is one floret per spikelet
 - Palea relative length
- palea is one half to fully as long as lemma
 - Reproductive system
- all the flowers on the plant have both carpels and stamens (synoecious)
 - Spikelet axis length
- 0 mm
 - Spikelet axis tip
- 
                                
                                    - there is an extension of the spikelet axis beyond the tip of the spikelet
- there is no extension of the spikelet axis beyond the tip of the spikelet
 
 - Spikelet disintegration
- the spikelet breaks off below the glumes
 - Spikelet length
- 3.5–7.5 mm
 - Spikelet number per node
- 0
 - Spikelet pedicel
- the spikelets have pedicels
 - Spikelet position
- the spikelets emerge from both the upper and lower halves of the inflorescence branches
 - Spikelets spiny
- the spikelets do not appear spiny
 - Tip of glume
- the tip of the glume is not divided (though it may have an awn on it)
 - Upper glume length
- 3.5–7.5 mm
 - Upper glume relative length
- the upper glume is more than one half as long as the lowest lemma
 - Upper glume shape
- the upper glume is widest at or below the middle
 
- 
                        Fruits or seeds- Seed length
- 2.1–2.8 mm
 
- 
                        Growth form- Horizontal rooting stem
- no
 - Lifespan
- the plant lives more than two years
 - Rhizomes
- yes
 - Roots
- the plant has rhizomes (horizontal underground stem with roots growing from it)
 
- 
                        Leaves- Basal leaves
- the plant has few or no leaves coming from the base of the flowering stem
 - Leaf auricles
- the leaves do not have auricles
 - Leaf basal lobe hairy
- NA
 - Leaf blade cross-section
- the leaf blade is more or less flat in cross-section, or slightly folded or rolled inwards
 - Leaf blade hairs
- the leaf blade is hairless, but it may have tiny prickles that give it a sand-papery feel
 - Leaf blade length
- 15–40 cm
 - Leaf blade texture
- the leaf blade is rough and sandpapery
 - Leaf blade width
- 3–19 mm
 - Leaf ligule length
- 2–10 mm
 - Leaf ligule type
- the leaf ligule is in the form of a membrane
 - Leaf margin glands
- there are no glands along the edges of the leaf blade
 - Leaf sheath closed around stem
- the margins of the leaf sheath are overlapping and not fused together except in the basal half (or less)
 - Leaf sheath hair type
- there are no hairs on the surface of the leaf sheath
 - Leaf sheath hairs
- there are no hairs on the surface of the leaf sheath
 
- 
                        Place- Habitat
- 
                                
                                    - terrestrial
- wetlands
 
 - New England state
- 
                                
                                    - Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
 
 - Specific habitat
- 
                                
                                    - edges of wetlands
- forests
- marshes
- river or stream floodplains
- shores of rivers or lakes
- swamps
 
 
- 
                        Stem, shoot, branch- Hairs at nodes
- the stem nodes are hairless or they have very sparse hairs
 - Plant height
- 28–185 cm
 - Roots at lower stem nodes
- 
                                
                                    - no
- yes
 
 - Stem hairs
- 
                                
                                    - the stem has hairs on it
- the stem is nearly to completely hairless
 
 - Stem node number
- 5–13
 - Stem orientation
- the stems are upright
 - Stem spacing
- the stems grow close together in compact clusters or tufts
 
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- widespread (S-rank: S5)
- Vermont
- fairly widespread (S-rank: S4)
From Flora Novae Angliae dichotomous key
1. Cinna arundinacea L. N
sweet wood-reed. Cinna arundinacea L. var. inexpansa Fern. & Grisc. • CT, MA, ME, NH, RI, VT. Riparian forests and terraces, stream banks, open marshes, swamps.
Native to North America?
Yes
Sometimes confused with
- Cinna latifolia:
- upper glume 1-veined and 2.6-4.1 mm long (vs. C. arundinacea, with upper glume 3-veined and 4.1-6.6 mm long).
Synonyms
- Cinna arundinacea var. inexpansa Fern. & Grisc.
![Stems and sheaths: Cinna arundinacea. ~ By John Hilty. ~ Copyright © 2025 John Hilty. ~ john[at]illinoiswildflowers.info ~ Illinois Wildflowers - www.illinoiswildflowers.info/index.htm](https://newfs.s3.amazonaws.com/taxon-images-239x239/Poaceae/cinna-arundinacea-ss-jhilty.jpg) 
                        ![Inflorescences: Cinna arundinacea. ~ By Christopher Noll. ~ Copyright © 2025 Christopher Noll. ~ clnoll[at]uwalumni.com ~ Robert W. Freckmann Herbarium, U. of Wisconsin-Stevens Point](https://newfs.s3.amazonaws.com/taxon-images-239x239/Poaceae/cinna-arundinacea-in-cnoll.jpg) 
                        ![Leaves: Cinna arundinacea. ~ By Andrew Nelson. ~ Copyright © 2025 Andrew Nelson. ~ andrew.nelson[at]oswego.edu   ~ Flora of Rice Creek Field Station - www.oswego.edu/academics/opportunities/rice_creek_field_station](https://newfs.s3.amazonaws.com/taxon-images-239x239/Poaceae/cinna-arundinacea-le-anelson2.jpg) 
                        ![Leaves: Cinna arundinacea. ~ By John Hilty. ~ Copyright © 2025 John Hilty. ~ john[at]illinoiswildflowers.info ~ Illinois Wildflowers - www.illinoiswildflowers.info/index.htm](https://newfs.s3.amazonaws.com/taxon-images-239x239/Poaceae/cinna-arundinacea-le-jhilty.jpg) 
                         
                        ![Plant form: Cinna arundinacea. ~ By Christopher Noll. ~ Copyright © 2025 Christopher Noll. ~ clnoll[at]uwalumni.com ~ Robert W. Freckmann Herbarium, U. of Wisconsin-Stevens Point](https://newfs.s3.amazonaws.com/taxon-images-239x239/Poaceae/cinna-arundinacea-ha-cnoll.jpg) 
                        ![Ligules: Cinna arundinacea. ~ By William and Linda Steere and the C.V. Starr Virtual Herbarium. ~ Copyright © 2025 William and Linda Steere and the C.V. Starr Virtual Herbarium. ~ Barbara Thiers, Director; bthiers[at]nybg.org ~ C.V. Starr Herbarium - NY Botanical Gardens](https://newfs.s3.amazonaws.com/taxon-images-239x239/Poaceae/cinna-arundinacea-li-cvstarr1.jpg) 
                         
                        ![Spikelets: Cinna arundinacea. ~ By Anna Gardner. ~ Copyright © 2025. ~ dlewis[at]ias.edu ~ Ada Hayden Herbarium - Iowa State U.](https://newfs.s3.amazonaws.com/taxon-images-239x239/Poaceae/cinna-arundinacea-si-agardner.jpg) 
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