Glossary

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Term
Description


abaxial
The underside of a leaf
achene
A dry and non-fleshy fruit that contains a seed. Commonly fruits of the Aster family
alternate
Leaves arranged alternately on the stem of the plant
anther
Produces pollen in a flower and is at the tip of the stamen. Often powdery yellow or orange
apiculate
Short and abrupt pointed tip
appressed
Laid flat
appressed hairs
Hairs that lie flat
auricle
Claw-like structures at the base of the leaf blade that usually clasp the sheath to the grass stem (culm)
awn
A bristle arising from a grass inflorescence
axil (of upper leaf)
Where the leaf joins with the stem
Large upper petal of the pea family (Fabaceae) with two lobes
basal internodes (stem)
Lower stem segments between branches or leaves
beak (fruit, seed)
Tip
bipinnate
Compound leaf with oppositely paired side stems along a central leaf stem. Leaves are arranged oppositely on the side stems
bract-like
Resembles bracts which are leaf-like structures at the base of flower heads
bracts
Leaf-like structures at the base of flower heads
bulb-like
Rounded resembling a bulb which is an underground stem with modified leaves to store nutrients and water
bunched
Dense patches
bunchgrass
Grows in clumps
C3/C4
C3 plants fix atmospheric carbon dioxide into sugar in the same cell, and are better adapted for cooler and moister environments than C4 grasses. C4 plants fix atmospheric carbon dioxide into a simple compound which is transported to a different leaf cell to be converted into sugars. C4 plants are better adapted than C3 plants for hotter environments
canescent (stem)
Covered in dense, fine and short hairs arising
cauline (leaf)
Arising from the stem
ciliated margins
Fine hairs along the leaf margin
clum
Stem of a grass or sedge
collar
A band of meristematic tissue where the leaf blade meets the sheath on grasses
composite flower
A flower that contains ray and disk flowers
compound stem
Branched
corymb
A flat-topped cluster of flowers. Stalks of outer flowers are longer than inner flower stalks. Outer flowers bloom first
(see illustration)
corymbiform
Corymb-like cluster of flowers
crenate margins
Blunt toothed leaf margin. Teeth have convex sides and the indentations between teeth is angular
(see illustration)
crown
Tip
cyme
A flower cluster in which the central flower blooms first. May be flat or round topped
cymiform
A cyme-like cluster of flowers
decumbent
Lying along the ground with extremities curved upwards
deltoid-lanceolate
Somewhat triangular with a wider base and narrower tip
dentate
A leaf margin that has widely spaced teeth with pointed tips. Between the tips, teeth are concavely curved
(see illustration)
disk flower
Small tightly packed flowers. Makes up the central disk of composite flowers like Asters
distal
Upper stem
dotted glands
Conspicuous pores
downy comas
A cluster of fluffy hairs
drupe
Fleshy fruit containing a single large seed
elliptic
Flattened circle with two axes of symmetry
entire
An untoothed leaf margin (see illustration)
erect
Upright; growing straight
feathery
Soft, branched, feather-like appearance
fibrous (roots)
Loose root system made up of many thin roots that originate from the stem base (not a large central tap root)
floret
A ray or disk flower. Many florets make up a compound flower 
glabrous
Hairless
gland
A stem or leaf pore
glandular
Surface is dotted with conspicuous pores
glume
Empty flower head scales of grasses
hairs, bristles
Thin thread-like structures which can be short, long, soft or rough. Can be used for wind seed dispersal or to improve water retention
hispid hairs
Long, stiff, straight hairs
hull
Outer layer, often referring to the outside of a seed or nut
inflorescence
Arrangement of flowers
internode
Lengthwise stem sections between leaves
lanceolate/lance shaped
A leaf shape with a wider base and a narrower tip
leaflet
A leaf-like unit of a compound leaf
(see illustration)
lemmas
Lower bracts of a grass floret
ligule
A structure of thickened tissue between the sheath and blade of the leaf. May be a papery membrane or a row of hairs
lobed
Distinct protrusions that may be angular or rounded
lyrate
Lobed leaf with the tip lobe being larger than the lateral lobes
margins
Leaf edges
mericarp
The two mericarps of a schizocarp resemble achenes and produce seeds
mid-cauline
Mid-stem
midrib/midvein
Central leaf vein
nerved
Veins or ribs, often referred to lateral leaf veins
nutlet
Seeds with a very hard seed coat from families such as the mint family (Lamiacea)
oblanceolate
A leaf shape with a narrower base than apex and a rounded tip
obovoid
Three-dimensional shape that is wider at the top than the bottom
opposite
A leaf arrangement where leaves are paired along the stem
palea
Inner bract of the two bracts beneath a grass floret
panicle
A branched cluster of flowers. Can be narrow and spike-like or broad
pappus
Modified sepals attached to the top of ovary. May be scales, or hair-like bristles
pedicel
Flower stalk
petal
Modified leaves that are usually colourful. Can be used to attract pollinators
petioles
A stalk that connects the leaf to the stem
pinnate
A compound leaf with leaflets arranged oppositely along a central stalk
pistil
Female structures of a flower consisting of the ovaries, style and stigma
plume (inflorescence)
Feathery
proximal
Base
raceme
Elongated cluster of flowers. Each flower has its own stem which attaches to a central flower stalk
ray flower
Petal-like outer flowers of a composite flower head
reduced distally
Leaf size decreases with increased stem height
reflexed petal
A petal that bends outward or downward at a sharp angle
revolute
Leaf margins that curl or roll downward
rhizomatous
Reproduces vegetatively (asexually) by rhizomes
rhizomes
Shallow, underground stems that can produce new clones 
rose hip
An aggregate fruit of a rose. Hairy achenes are inside a red fleshy receptacle
rosettes
Whorled basal leaves
scabridulous
Slightly rough
scabrous
Surface is rough with short hairs
secund
Arising only from one side
seed coat
Outer protective layer of a seed
self compatible
Can reproduce if pollinated with its own pollen
sepal
Leaf-like structure at the base of the flower. Usually surrounds the ovaries and provides support and protection to developing seeds. May have a petal-like appearance
serrated
Leaf margins are toothed. Teeth are approximately the same size
sessile
Leaf attaches to stem directly without a petiole
sheaf/sheath
An extension of the leaf that wraps around the stem. Found in grasses, sedges and some forbs. 
simple leaf
Not divided into leaflets like a pinnate or compound leaf
spikelet
Floral structure of a grass or sedge made up of pairs of scales which contain florets
stalkless
Without a stem
stamen
Male reproductive organs of a flower made up of the filament (thin stalk that supports the anther) and anther
stigma
Tip of the pistil that receives pollen
stipules
Leaf-like structure where the leaf attaches to the stem. Often in pairs
stoloniferous
Reproduces vegetatively (asexually) by stolons
stolons
Creeping aboveground runner stems that can produce new clones 
style
Thin and long structure connects the stigma to the ovary in a flower. May be 1 or multiple in a flower
subentire
Almost entire leaf margins
sublyrate
Almost lyrate
suborbicular (seed)
Almost spherical
subumbelliform
Umbel-like cluster with flowers arising from the same point
succulent
Thickened, fleshy, retaining water
tap root
A root system that has a central root that may be slender or stout with branching finer roots
tepal
Petals and sepals of flowers that have similar appearances
terete
Round stem
terminal
Located at the end, often referring to flowers at the end of stems
ternate
Divided into three groups
toothed
Serrated
tufts
Feathery or bristly bunches of hair
umbel
Cluster of flowers that has flower stalks developing from the same location
undulate
Wavy
venation
Pattern of veins in a leaf
villi
Fuzzy, hair-like structures
whorled
A arrangement with 3 or more structures (usually leaves or scales) that are connected at same location on the stem and point outward in different directions
winged
A thin papery or leaf-like membrane that often runs along the edge of a seed or along a stem or stalk