Ferns of the Organ Mountains

Outline: 1.What are ferns? -features; life cycle; special characteristics like sori and gametophytes; desert adaptations 2.The Organ Mountains -a little geography and geology, and some of the habitats where you ’ ll find ferns. 3.Ferns in the Organs -some of the common ferns found in the Organ Mts. and where you might see them.

1: What are ferns? Ferns are plants that: -have vascular tissue (unlike mosses and liverworts) -have “ true ” leaves (unlike clubmosses, spikemosses, and horsetails) -do not have seeds (unlike conifers and flowering plants) -do not have flowers (unlike flowering plants) They reproduce via spores, produced in structures called sori (which we ’ ll see in a moment). These spores grow into a structure called a gametophyte; it ’ s called that because it produces gametes (sperm and eggs). When those gametes join, you get a new sporophyte (what we call the typical leafy plant that produced the spores, to distinguish it from the gametophyte).

Fern life cycle sporophyte sori on leaves spores gametophyte spermeggs haploid (n) diploid (2n) (meiosis) (fertilization) Let ’ s not worry about diploid vs. haploid much for the moment. The general idea is that a sporophyte, what you ’ re used to thinking of as a fern, makes spores. The spores then grow into a gametophyte, which makes sperm and eggs. The sperm and eggs then join to form a new sporophyte.

Sporophyte

Sori

Gametophytes R. Moran

Sori: why are they important? Sori have a lot of variability between groups, and are often very distinctive. So we use them a lot for identification.

Gametophytes: why are they important? Ferns are a bit like amphibians.

Digression: frogs... Adult frogs in desert areas fall into two categories: some, like spadefoot toads (left) can become dormant in dry periods; others, like leopard frogs (right) need constant water.

Frogs, continued... But, whether the frog is a spadefoot or a leopard frog, its tadpoles need constant water.

Sporophytes are like adult frogs Though all fern sporophytes need water for active growth, like frogs they fall into two categories: those that live in dry microhabitats and become dormant during dry periods, and those that can only survive in microhabitats that provide constant water.

Gametophytes are like tadpoles But, whether the sporophyte can survive drying or not, the gametophyte can ’ t. It needs constant water to survive and a film of water for fertilization; if it dries, it dies. So for desert ferns, the gametophyte is often the limiting step. R. Moran

Gametophytes 2 So how do ferns deal with the limitations of drought- intolerant gametophytes? Two main ways: 1.Have the gametophyte around for as short a time as possible. While ferns from wet areas might have their gametophytes sitting around for 3 months or more, desert ferns can go from spore to new sporophyte in as little as two weeks! 2.Give up on sex! If a fern can skip that pesky sperm/egg part, it can get to the sporophyte stage more quickly and doesn ’ t need a film of water for fertilization.

2. The Organ Moutains This is a NASA satellite image

The Organ Mountains The figure at right shows a simplified view of the geology of the Organs. Purple is rhyolite, a volcanic, greyish rock. Blue is limestone, a sedimentary rock that forms in oceans. Red is quartz- monzonite, a kind of granite. Different rocks, different ferns!

The Needles: granite.

The best fern habitats in the granite part of the mountains are rocky, relatively moist slopes with occasional seeps that have water most of the year.

Bishop ’ s Cap: limestone.

Bishop ’ s Cap has dry, gravelly slopes and ravines; a few ferns can survive on the slopes, others are limited to sheltered microhabitats.

La Cueva & Dripping Springs: rhyolite.

The rhyolite areas offer steep, narrow canyons. These provide areas of constant water that some ferns need and a wide range of good rocky outcrops and slopes.

3. Ferns in the Organ Mts. Aspleniaceae: ? Asplenium palmeri ? Asplenium resiliens Asplenium trichomanes Dennstaedtiaceae: Pteridium aquilinum Dryopteridaceae: Cystopteris reevesiana Dryopteris filix-mas Phanerophlebia auriculata Woodsia cochisensis Woodsia neomexicana Woodsia phillipsii Woosdia plummerae Pteridaceae: Adiantum capillus-veneris Argyrochosma limitanea Astrolepis cochisensis Astrolepis integerrima Pteridaceae, cont.: Astrolepis sinuata Astrolepis windhamii Bommeria hispida Cheilanthes bonariensis Cheilanthes eatonii Cheilanthes feei Cheilanthes fendleri Cheilanthes lindheimeri Cheilanthes tomentosa Cheilanthes villosa Cheilanthes wootonii Cheilanthes wrightii ? Cheilanthes yavapensis ? ? Notholaena grayi ? Notholaena standleyi Pellaea atropurpurea Pellaea intermedia Pellaea truncata Pellaea wrightiana The short version: 31 ferns definitely in the Organs, 3 might be; 4 families of ferns in the Organs, Pteridaceae (brake family) with the most species.

Ferns and geology. Aspleniaceae: Asplenium resiliens Asplenium trichomanes Dennstaedtiaceae: Pteridium aquilinum Dryopteridaceae: Cystopteris reevesiana Dryopteris filix-mas Phanerophlebia auriculata Woodsia cochisensis Woodsia neomexicana Woodsia phillipsii Woosdia plummerae Pteridaceae: Adiantum capillus-veneris Argyrochosma limitanea Astrolepis cochisensis Astrolepis integerrima Pteridaceae, cont.: Astrolepis sinuata Astrolepis windhamii Bommeria hispida Cheilanthes bonariensis Cheilanthes eatonii Cheilanthes feei Cheilanthes fendleri Cheilanthes lindheimeri Cheilanthes tomentosa Cheilanthes villosa Cheilanthes wootonii Cheilanthes wrightii Notholaena standleyi Pellaea atropurpurea Pellaea intermedia Pellaea truncata Pellaea wrightiana Purple: occurs on rhyolite; Orange: occurs on rhyolite and granite; Blue: occurs on limestone; Green: occurs on limestone and rhyolite/granite.

Ferns and geology, cont.. Aspleniaceae: Asplenium resiliens Asplenium trichomanes Dennstaedtiaceae: Pteridium aquilinum Dryopteridaceae: Cystopteris reevesiana Dryopteris filix-mas Phanerophlebia auriculata Woodsia cochisensis Woodsia neomexicana Woodsia phillipsii Woosdia plummerae Pteridaceae: Adiantum capillus-veneris Argyrochosma limitanea Astrolepis cochisensis Astrolepis integerrima Pteridaceae, cont.: Astrolepis sinuata Astrolepis windhamii Bommeria hispida Cheilanthes bonariensis Cheilanthes eatonii Cheilanthes feei Cheilanthes fendleri Cheilanthes lindheimeri Cheilanthes tomentosa Cheilanthes villosa Cheilanthes wootonii Cheilanthes wrightii Notholaena standleyi Pellaea atropurpurea Pellaea intermedia Pellaea truncata Pellaea wrightiana Purple: occurs on rhyolite; Orange: occurs on rhyolite and granite; Blue: occurs on limestone; Green: occurs on limestone and rhyolite/granite. Notice: the rhyolite areas have the most ferns, and seven of them don ’ t occur in other parts; no ferns occur only on granite but a lot occur on rhyolite and granite; four ferns occur only on limestone.

Fern families So, I told you sori are useful in identification, and here ’ s the proof... we ’ ll look at the three families you ’ re likely to see in the Organ Mts.

Aspleniaceae (spleenwort family) In this family, the sori are oval or linear, with a flap (called the indusium) along one side. These ferns require nearly constant moisture.

Dryopteridaceae (shield fern family) In this family, the sori are round, with that flap (indusium), forming a shield or cup-like structure. These ferns also require nearly constant moisture.

Pteridaceae (brake family) In this family, the sori form lines along the edges of the leaflets, protected by the edge of the leaf or unprotected. These are the true arid-dwelling ferns, living in the driest habitats.

Pteridaceae, cont. Aspleniaceae: Asplenium resiliens Asplenium trichomanes Dennstaedtiaceae: Pteridium aquilinum Dryopteridaceae: Cystopteris reevesiana Dryopteris filix-mas Phanerophlebia auriculata Woodsia cochisensis Woodsia neomexicana Woodsia phillipsii Woosdia plummerae Pteridaceae: Adiantum capillus-veneris Argyrochosma limitanea Astrolepis cochisensis Astrolepis integerrima Pteridaceae, cont.: Astrolepis sinuata Astrolepis windhamii Bommeria hispida Cheilanthes bonariensis Cheilanthes eatonii Cheilanthes feei Cheilanthes fendleri Cheilanthes lindheimeri Cheilanthes tomentosa Cheilanthes villosa Cheilanthes wootonii Cheilanthes wrightii Notholaena standleyi Pellaea atropurpurea Pellaea intermedia Pellaea truncata Pellaea wrightiana Just a reminder: most ferns in the Organ Mts. are in Pteridaceae; no surprise given that it ’ s the most drought-tolerant of the families.

So, now I ’ ll go through the three major parts of the Organs and show you some ferns you ’ d see there. Let ’ s start with Bishop ’ s Cap (A Mt. is similar).

Astrolepis cochisensis (Cochise cloak fern): most common fern on dry limestone.

Astrolepis cochisensis (Cochise cloak fern): most common fern on dry limestone.

Astrolepis integerrima (hybrid cloak fern): also on dry limestone

Cheilanthes feei (Fee ’ s lip fern): under overhangs, locally moist limestone.

Cheilanthes feei (Fee ’ s lip fern): under overhangs, locally moist limestone.

In the granite portion of the mountains, you can see a number of ferns at Aguirre Spring

Cheilanthes fendleri (Fendler ’ s lip fern): common in cracks in granite

Cheilanthes fendleri (Fendler ’ s lip fern): common in cracks in granite

Cheilanthes fendleri (Fendler ’ s lip fern): common in cracks in granite

Cheilanthes eatonii (Eaton ’ s lip fern): usually under or between granite boulders

Cheilanthes eatonii (Eaton ’ s lip fern): usually under or between granite boulders

Pellaea truncata (spiny cliff-brake): amid granite boulders, lower elevations

Woodsia neomexicana (New Mexican cliff fern): in moist soil or under granite boulders

Woodsia phillipsii (Phillips ’ cliff fern): in moist soil or under granite boulders

And, last, let ’ s consider some of the ferns you ’ d near at Dripping Springs; we ’ ll see many of these on the next field trip!

Some will be the same as what we ’ d see at Aguirre, but others won ’ t.

Notholaena standleyi (star cloak fern): in cracks in exposed rhyolite

Cheilanthes bonariensis (golden lipfern): occurs in moist soil near pools and seeps

Cheilanthes bonariensis (golden lipfern): occurs in moist soil near pools and seeps

Pellaea atropurpurea (purple cliffbrake): occurs in rocky soil under oaks

Pellaea atropurpurea (purple cliffbrake): occurs in rocky soil under oaks

Pellaea wrightiana (Wright ’ s cliff-brake): found in cracks in exposed rhyolite & among boulders

Pellaea wrightiana (Wright ’ s cliff-brake): found in cracks in exposed rhyolite & among boulders

Astrolepis sinuata (wavy cloakfern): occurs in rocky soil on moist slopes

Phanerophlebia auriculata (eared veinfern): occurs under boulders in the moist bottoms of steep canyons

Asplenium resiliens (maidenhair spleenwort): occurs on moist rock in seeps

Asplenium trichomanes (maidenhair spleenwort): occurs on moist rock in seeps

Asplenium trichomanes (maidenhair spleenwort): occurs on moist rock in seeps

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