Tuesday, March 24, 2020

Something About Maples


Maple trees run deep in our consciousness.  These magnificent trees grace the national flag of Canada, give us maple syrup and even give us some of the bats in Major League Baseball.  Maples are classified in the genus Acer and most are found in the Northern Hemisphere from Asia through Europe to North America. All maples have opposite leaves (two leaves come out at a node) and the leaves are lobed, or in a couple of species compound.  In the fall of the year, maple leaves turn red or orange or yellow and generally put on a spectacular show.  Another characteristic of maples is their winged seeds that fly like helicopters to disperse the plant.  There are more than 120 Acer species worldwide.  Asia has the highest diversity of maples but there are about a dozen species in North America. 

The winged fruits, the samaras, of Red Maple (Acer rubrum)

Acer rubrum, the Red Maple is perhaps the most common deciduous tree in North America.  It grows from the Canadian Maritimes, west to the Great Lakes, South to Texas and down the length of the Florida peninsula.  Red maple’s great range is due to its adaptability.  This tree can grow in poor rocky soil or with its feet wet in a river bottom swamp.  Red Maple thrives in rich, slightly acidic, soil and can grow to a height of more than 100 feet.  Red maple reproduces in late winter when it puts out small red flowers. Each tree bears separate male and female flowers.  The petals of maples are tiny because they are not trying to attract insects but are wind pollinated.  The female flowers produce winged fruits, the samaras.  Red Maples usually make a pair of samaras per flower and these are bright red.  The fruits mature and fly from the tree during the summer. 

Early spring male flowers of Red Maple.  These flowers have highly
reduced petals and five stamens.


Female flowers of Red Maple.  Each has two
stigmas extending from the top that accept pollen .


Female flowers of Red Maple with young developing fruits.


Red Maple with maturing samaras.  They
will turn red in a few days.


A large group of Red Maple fruits beginning to turn red.

Sugar Maple (Acer saccharum) has a more northerly distribution than Red Maple.  It was originally absent from the Southeastern United States but is now widely grown as an ornamental tree.  Sugar Maple’s claim to fame is as the source of maple syrup.  In late winter, the tree begins to mobilize sugars that were stored in the roots and transports them to the shoots.  There the sugar is used to power the growth of the new leaves.  For the last couple of winters students and professors at Catawba College in Salisbury, NC, have been tapping maples on campus and making their own syrup.   These sugarers inserted taps into the sapwood of the tree, collected the sap and boiled it to make the syrup.  North Carolina is not the best place for a maple syrup operation but these students and professors collected 20 gallons of sap and made a half gallon of syrup.    

Fall leaves of Sugar Maple (Acer saccharum).

A Catawba College student using a drill to tap
a Sugar Maple tree. Photo courtesy of Dr. Jay Bolin.



                                         
                                              Sap dripping from a tap in a Sugar Maple tree.
                                                       Video courtesy of Dr. Jay Bolin.


A Catawba College student sampling maple syrup.
Photo courtesy of Dr. Jay Bolin.

Maples offer delight throughout the year.  They signal the end of winter with their red flowers.  They enchant with helicoptering fruit. And in the fall, they dazzle with their brightly colored leaves.  Enjoy.

Wednesday, March 4, 2020

Spring Ephemerals

In early spring, before the trees leaf out, the forest floor is flooded with light. In this narrow window of warming temperatures and abundant sunshine, a hardy group of plants rush to reproduce. They are the spring ephemerals. These plants are perennials that spend most of the year underground, as a root or stem. But, as the days lengthen the spring ephemerals push up their leaves, produce flowers, make fruits, then die back to await the next spring. In colder regions, the spring ephemerals can flower while there is still snow on the ground.

Hepatica (Anemone americana), a spring ephemeral, in flower and showing
its three lobed leaves.  

A Piedmont deciduous forest
in late February.  This is prime habitat for spring ephemerals. 
Trout Lily (Erythronium americanum) is a beautiful spring ephemeral with oblong, pointed green leaves mottled with purple. This leaf pattern looks like a trout in a stream and gives the plant its common name.  Plants bearing flowers usually have a pair of leaves. Trout lily flowers are yellow with reflexed petals and deep reddish-brown stamens. Trout Lilies can propagate vegetatively and grow in large colonies.

Trout Lily (Erythronium americanum) with its trout patterened
leaves and yellow flowers.

Closeup of Trout Lily flower showing its reddish-brown stamens
and yellow, reflexed petals..

Trout Lilies showing the paired leaves. 

Bloodroot’s (Sanguinaria canadensis) dramatic name comes from its deep-orange colored sap. Bloodroot, like other members of the poppy family produces toxic molecules to protect the plant from animal grazers. Bloodroot flowers in late winter and makes a single flower with many white petals and bright yellow stamens. Bloodroot generally makes one multi-lobed leaf that wraps around the base of the flower.

Bloodroot (Sanguinaria candensis) flower just opening. Note the lobed
leaf at the base of the flower. 

Bloodroot flower opening. 

Closeup of Bloodroot flower. 

Bloodroot flower. 

Bloodroot plant with lobed leaf and a developing fruit.
For such a small plant, Hepatica or Liverleaf (Anemone americana) is quite spectacular. The name Hepatica comes from the Latin for liver. The second common name, Liverleaf, echoes the Latin because, like livers, the leaves of this plant have lobes. Hepatica found a use in folk medicine to treat liver disease based on the Doctrine of Signatures. This medieval medical idea stated that plants advertised their usefulness by their appearance. So by the Doctrine of Signatures the Toothwort plant was used to treat toothache, Spleenwort to treat disorders of the spleen and Hepatica to treat liver disease. Hepatica makes the first purple flowers of spring. These flowers rely on the earliest flying pollinators like bumblebees for reproduction.  But, if the spring is cold and pollinators are not available, Hepatica can also carryout self-pollination. Unlike most spring ephemerals, the leaves of Hepatica persist through the year. The leaves turn dark red in fall and the following spring they are replaced the by new, green leaves.

A Hepatica plant with multiple flowers.

In the Piedmont of North Carolina, look for spring ephemerals from late February to mid-April. They run their rapid life cycle in the leaf litter of mature forests. But look quick, they are ephemeral.