Polypodiaceae (Ferns) Flashcards
1
Q
What to look at when attempting to ID a fern
A
- fronds
- turn it over and look at reproductive structures
- look at frond stalk-taking note of color and texture
2
Q
Frond
A
- Consists of a stalk with a green, leaf-like growth emerging from it
- Subdivided into multiple leaf-like growths
- Pinna-each large blade division is called a “pinna”, plural “pinnae” (pin-knee)
3
Q
Terms associated with Pinna
A
- Pinna-each large blade division is called a “pinna”, plural “pinnae” (pin-knee)
- Pinnules- the lobes the pinnae are divided into
- Lobes- further division of the pinnules
- fronds that are divided again and again are called finely-cut
- the more the leaf-like material is divided, the more feathery it will look
4
Q
Fern Reproductivity
A
- Do not produce seeds, but spores
- Sori (sore-eye)/Sorus-house the microscopic spores while they are developing
- Sometimes easily seen on underside of frond. Other times the presence of a sori just seems to change the color, texture, and shape of the frond
5
Q
Location of Sori
A
- Some ferns produce sterile fronds (fronds without sori), while also producing one or more fertile fronds (with sori)
- Other ferns consist entirely of fertile fronds
- In others, the sori only emerge from some of the pinnae, while they are absent from the rest of the pinnae
6
Q
The Stalk
A
- Stipe- the part of the stalk from the ground to the beginning of the frond’s leafy area
- Rachis- the portion of the stalk in which the leafy material is attached
7
Q
Spleenworts
A
- Do not have spherical sori
- Each sorus is similar to the shape of a spleen/kernel of rice
- elongated, oval shaped sori
8
Q
A
Christmas Fern
- ”bump” on the pinna near the stalk
- imagine Santa is the bump and he is sitting on a sled
- Spores only develop on top portion of frond-the fertile pinnae curl up as the spores develop
- Sori underneath pinna are not distinctly visible but they cause the entire underside to turn brown
9
Q
A
Christmas fern
- Spores only develop on top portion of frond-the fertile pinnae curl up as the spores develop
- Sori underneath pinna are not distinctly visible but they cause the entire underside to turn brown
10
Q
Why are they called “Christmas” ferns?
A
People in the 1800s used their evergreen fronds to decorate their homes for Christmas
11
Q
A
Maidenhair Wood Fern
- long, black stipe the divides into two rachis, which bend in a semi-circle towards eachother
- reddish fiddleheads with wirey hairs
- very slender stipes
- notched or lobed fan-shaped pinnae with very short stalks
- spores are found along the edge on the underside of the pinnae, linear to oblong sachi
12
Q
A
Maidenhair Spleenwort
- very short, almost invisible stipe
- often grows right out of rock, particularly limestone
- pinnae are shorter than maidenhair wood fern, nearly as wide as long
- Pinnae edges scalloped
- State threatened in MN
13
Q
A
Lady Fern
- reddish-wine colored stalk
- pinnae tend to be widely spaced on its rachis
14
Q
A
Maidenhair Wood Fern
- very slender stipes
- notched or lobed fan-shaped pinnae with very short stalks
- spores are found along the edge on the underside of the pinnae, linear to oblong sachi
15
Q
A
Lady fern
- Leaflets have rounded or pointed lobes and tips, rounded or pointed (but not bristly) teeth
- forked veins that do not typically extend quite all the way to the leaflet edge
16
Q
A
Lady Fern
- The sori (cluster of spores) develops on the back of the leaf blade in summer and is typically curved to hook-shaped
17
Q
A
Lady Fern
- The slender stem is covered in dark brown scales.
18
Q
A
Maidenhair Wood fern
- reddish-purplish fiddleheads with white wirey hairs
19
Q
A
Christmas fern
- Fiddleheads are light green and densely covered in silvery scales.
20
Q
A
Cinnamon fern
- closely resembles Interrupted fern. (ULI-unlike inter.)
- no sori on underside of pinnae, ULI, instead they’re all on a central fertile frond that shoot up
- White fuzz present where pinna attaches to rachis, ULI
21
Q
A
Cinnamon fern
- closely resembles Interrupted fern. (ULI-unlike inter.)
- no sori on underside of pinnae, ULI, instead they’re all on a central fertile frond that shoot up
- White fuzz present where pinna attaches to rachis, ULI
22
Q
A
Cinnamon fern
- closely resembles Interrupted fern. (ULI-unlike inter.)
- no sori on underside of pinnae, ULI, instead they’re all on a central fertile frond that shoot up
- White fuzz present where pinna attaches to rachis, ULI
23
Q
A
Cinnamon fern
- Fiddlehead-As the fern emerges from the ground in early spring it is covered in a light brownish-colored wool but it is quickly lost.
- Similar to Interrupted fern
24
Q
A
Interrupted fern
- The sterile leaves grow arching in a circular clump with the fertile leaf (if present) growing more erect in the center.
25
Q
A
Interrupted fern
- The capsules are initially dark green but turn dark brown with maturity. After releasing the spores, the capsules whither away leaving a large gap (i.e. “interruption”) in the middle of the leaf.
26
Q
A
Interrupted fern
- no white pubescens where the pinna attaches to the rachis, unlike the cinnamon fern
- no sachi on the underside, like cinnamon fern
27
Q
A
Interrupted fern
- Fiddlehead- As the fern emerges in the spring it is covered in a light wool but it is quickly lost.
28
Q
A
Ostrich fern
- Sterile and fertile fronds
- sterile pinna taper abruptly toward their tips, while toward their bases the pinna become very small (less than 1” long — makes them easily identifiable (rare trait)
- Pinnules of the sterile leaves are relatively short (2-12” in length), light green to brown, and relatively stout
29
Q
A
Ostrich fern
- Sterile and fertile fronds
- sterile pinna taper abruptly toward their tips, while toward their bases the pinna become very small (less than 1” long — makes them easily identifiable (rare trait)
- Pinnules of the sterile leaves are relatively short (2-12” in length), light green to brown, and relatively stout
30
Q
A
Ostrich fern
- Ostrich Fern has at least 1 spike 20 to 50 inches tall growing in the center of the leaf clump. 25 or more pairs of hard tubular-shaped “pods” contain the spores in somewhat bead-like structures. These fertile fronds are initially green but turn dark brown with maturity and persist through the winter, releasing spores the following spring before dying back.
31
Q
A
Ostrich fern
- Veins are straight, not forked, in a chevron pattern most easily seen on the underside. The leaflet midrib may be covered to varying degrees in short hairs.
32
Q
A
Sensitive fern
- Deciduous fronds die at first site of frost (sensitive)
- Bright green sterile fronds that run along rachis
- Pinnae are widely spaces along rachis
- Upper pinnae have smoother edges while lower are deeply lobed/wavey
33
Q
A
Sensitive fern
- 5 to 11 pairs of branches contain the spores in bead-like structures tightly packed along a branch. These fertile fronds turn brownish black at maturity and persist through winter, releasing the spores the following year.
