Fern Fun at Mary Gray Bird Sanctuary

By Jack Berninger

My wife, Elaine and I have spent many enjoyable days at Mary Gray looking and locating ferns.  Ferns are primitive vascular plants, the first to have true roots, stems and leaves. They have prospered on earth for over 300 million years and were plentiful in the swamps during the Carboniferous Time Period. They formed much of the coal found throughout the world.  Dinosaurs feasted on these plants during their long reign.

I want to share with you a guided fern walk, which takes about one hour, on Trail 1 “Wildflower” and Trail 3 “Tulip Popular”. Along these trails you should be able to locate twelve of the ferns listed on the information leaflet.  Start on the Wildflower trail off the entrance road.  There are seven foot bridges along the trail and these will be used as some guide posts.

As you enter the trail just ten feet look on the right next to a 4” diameter fallen log and you can find FRAGILE FERN with Sori dots (spore cases) on the back of the Pinnules (small leaves).  Ferns reproduce by spores not seeds. The spores fall to the ground and grow into another plant structure called the Prothallus (about dime size) which produces male and female reproductive structures that when fertilized grow into the adult fern plant you find.  Once you I.D. a fern you will locate others along the trail.  The Next fern is located 20’ from the Fragile Fern on the right across from a rotting log. It is called RATTLESNAKE FERN, a small 6-12” fern with three parted pinnae (leaves).  The fertile stalk with the spores grows from the pinnae (leaf) base on the rachis (stem). It is not present or very withered in mid-July. This fertile stalk easily I.D.’s this fern in June.  Just 10’ farther is the most abundant fern at the preserve, the dark green CHRISTMAS FERN with an upward ear at the end of each pinnae (leaf).  This fern is really ubiquitous so you can’t miss it. The sori (spore cases) are on the back of some of the leaves. This fern remains green most of the year and was used for decorations and the pinnae (leaves) resemble a Christmas stocking.  Continue walking past the Wildflower Trail plaque on the right and stop just before the first bridge.  This is the only location of the next fern called SENSITIVE FERN growing along the edge of the creek on the left just before the bridge.  Look carefully. The pinnae, fairly wide, are connected to each other by a small flange along the rachis (stem).  This plant is sensitive to frost.  Cross the bridge and continue on about 100’ and look on the left for a large cut fallen tree. Across from this tree’s huge root on your right is a small delta along the creek where you will see patches  of OSTRICH FERN.  The rachis (stem) is groved especially near the base and the pinnae (leaves) abruptly narrow at the top and gradually narrow on the bottom.  Enjoy your walk crossing bridges 2 and 3, bear right at the campground (CG) trail marker and continue across the 4th bridge. Cross and continue uphill and look to the left just 20’ before the 5th bridge. There is a very large Tulip Popular tree on the left. Look at the left side base of this tree for the light green NARROW LEAF GLADE (SPLEENWORT) FERN.  It is similar to Christmas Fern but the pinnae have no ear, smooth margins and it is lighter green.  Just as you step on this bridge(5th) look on the right for one of the most beautiful and only group of MAIDEN HAIR FERN. The top of this fern is circular like a Greek maidens crown. Stipe and rachis (stem) are purplish-brown and shiny. Between the close 5th and 6th bridges is a group of SILVERY (SPLEENWORT) GLADE FERN on the right side of the trail just 7’ short of bridge 6 among the Christmas fern. The stipe and rachis (stem) are very hairy. Cross the bridge and find a larger patch of this fern up the hill on the left.  Walk another approximately 40’ and look on the left for a group of BROAD BEECH FERN. The bottom pinnae (leaves) are large and pointed downward. Also a slight flange connects pinnae along  the rachis.  Sori, if found, are near the margins of the pinnules (leaflets).  Continue and cross 7th bridge and walk about 200 feet past a large cut fallen tree log  that was across the trail.  Now look for a patch of LADY FERN on the left.  Sori, if found, are on the back of the fringed pinnules and are sickle shaped.  Lower pinnae point downward and no scales are on the rachis.

Enjoy the remainder of this trail 1. Turn left at the (CG) marker which will return you to the camp area and road. Have a nice lunch under the picnic shelter by the red (Markle) barn.

PART II Trail 3

If you wish to find a new fern and three fern allies first look around the lake edges for one ally called Equisetum, looks like small green horse tail, then take Trail 3 (Tulip Popular) starting behind red Markle Barn to the new bridge #1. Count the bridges. Turn right after crossing the bridge and continue past the Woodpecker Trail turn off, keep to the right on Popular trail about 48’ on the left in early fall will be a GRAPE FERN (fertile spore frond, which grows from the base of this fern at ground level, may not be noticeable until late September). Walk another 45’ from the Grape Fern look on the right just 3’ past a fallen protruding small dead tree root and next to a 18” diameter Tulip Popular tree for a new fern called EBONY SPLEENWORT. Look close as it is hard to find. Stipe/Rachis (stem) are shiny purplish-black. Sori on back of fertile frond pinnae. Another GRAPE FERN can be found just 6’ before bridge two. This trail is enjoyable to walk with varied habitat and nine bridges.

Past 5th bridge about 150’ midway up the hill on the right is SILVERY GLADE FERN. Go another 20’past some Maiden Hair fern on the right and look for the light green, fringed pinnules (leaflets) of the LADY FERN on the right mixed among some Christmas Fern. Go another 20’ on the left and find a good patch of BROAD BEECH FERN with bottom pinnae pointing downward. Over 6th bridge midway up the hill on the left is a grouping of NARROW LEAF GLADE FERN. Almost at the top of this hill along both sides of the trail is a large group of SILVERY (SPLEENWORT) GLADE FERN. Continue past bridges 7 and 8 and as you approach bridge 9 look for a grass like bamboo sectioned stalk (thin and one-two feet high) called SCOURING RUSH. It is a fern ally. It was used for cleaning pots and pans. On the way back take the service road and go up the Crataegus Trail on the left and look for another fern ally called RUNNING GROUND PINE located under the cedar and pine trees. Some will have the spore containing strobilus (fork like) sticking up from the plants. Return to the parking lot and savor some unusual finds and good exercise at our great Mary Gray. The ADDER’S TONGUE FERN can be found from late April until second week in June along trail 6 about 100 feet west on the left. A red marker is in the area.

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