Monthly Archives: October 2012

Witch-hazel Michigan’s late-bloomer

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Hamamelis virginiana, Michigan

Witch-hazel flowers

Witch-hazel (Hamamelis virginiana) is a large shrub or small tree that blooms in the fall in Michigan. It grows in the Lower Peninsula and the western half of the Upper Peninsula. Outside of Michigan, it grows throughout the eastern United States reaching its western limit in Texas and Oklahoma. It is the last of our native woody plants to blossom. The flowers appear in most years after the plant has dropped its leaves. The yellow flowers with their four wiry petals form a pretty sight in the fall woods.

Hamamelis virginiana, Witch-hazel, Michigan

Witch-hazel, Oakland Co., Michigan

Hamamelis virginiana, seedpod,

Witch-hazel, Tenhave Woods, Oakland Co., Michigan.

The seeds ripen about the same time as the plant flowers. The seedpods shoot the seeds ten to fifteen feet. When I was a boy in Middle School, I had a Witch-Hazel branch with seedpods in my bedroom. (Doesn’t every boy go through this stage?) During the night, I heard a strange “Ping.” The seedpods were drying out and shooting their hard BB-sized seeds against my bedroom mirror.

Spiny Witch-hazel Gall

Spiny Witch-hazel Gall

This plant also produces Spiny Witch-hazel Galls. An aphid crawls into a leaf bud and secretes an enzyme. The irritation causes the plant to produce the gall around the aphid. The aphid reproduces within the gall and the gall provides a food source for the young. The life-cycle is more complex than this involving a secondary plant species host and some broods that are solely females. I cut open a gall from my garden, expecting it to be solid, but instead I discovered it was hollow. Several female aphids (the ones with wings) and at least one male were inside.

I love to see these flowers on their bare branches as I walk though the fall woods. Get out into a rich woods and see if you can find these last flowers of the year.

Spiny Witch-hazel Gall

Spiny Witch-hazel Gall with Aphids

A Small “Big” Tree

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Staghorn Sumac Rhus typhina

Staghorn Sumac Girth

Staghorn Sumac Twig

Staghorn Sumac

Big tree hunting is a great sport. Many people find and report large trees but it is the largest of the normally small species that have always interested me. Record small tree species include a 5-inch diameter Witch-hazel, a 6-inch diameter Highbush-cranberry, a 7-inch diameter Red Elderberry, and an 11-inch diameter Pawpaw. Most people walk by trees that are less than a foot in diameter without ever thinking “big tree.”

Recently I found two large Staghorn Sumacs (Rhus typhina) on the campus of Oakland University in Rochester, Michigan. They are along Pioneer Drive southeast of Pawley Hall. The largest one is approximately one foot in diameter. Staghorn Sumac is a common species in Michigan that normally is just shrub size. It gets the name “staghorn” because the hair on the twigs resembles the velvet on the horns of a stag.

These two are not Michigan state champion size but are close. Champions are determined by a point system. The points equal the height in feet, plus the girth in inches (four-and-a-half feet from the ground), plus one-fourth of the average spread. The Michigan state champion Sumac scores 72 points. I measured the height of the largest Oakland University Sumac as 20-feet (by the stick method), its circumference at 4-feet above ground as 37-inches (the tree forks below the four-and-a-half-feet height) and its canopy spread at 26-feet x 23-feet. It scores 63 points. Currently there is no national champion Staghorn Sumac. National champions must be measured every ten years and our state champion’s data is older. The Oakland tree might qualify as a national champion.

The stick method to estimate tree height involves simple triangulation. You hold a straight stick perpendicular to the ground with your arm parallel to the ground and your hand level with your eye. The height of the stick above your hand must equal the distance from eye to the base of the stick. This forms a right triangle with two 45-degree angles. Position yourself so that when you sight over the top of the stick you see the top of the tree. The distance you are from the tree equals the approximate height of the tree.
The Michigan Botanical Club maintains the state’s big tree list and their website explains methods for measuring trees. The group American Forests maintains the national registry. 

You never know what you will find in the natural world by just keeping your eyes open.

Staghorn Sumac Rhus typhina

Two Large Staghorn Sumacs on Campus of Oakland University, Pawley Hall in Background

Note: Both of these trees have been removed. Updated 8/10/2021

Michigan Frog Weekend

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Green Frog

Green Frog, Cheboygan Co., Michigan

Last weekend I traveled north to the Straits of Mackinaw and it turned into a frog weekend. At Mill Creek State Park we found several Green Frogs (Rana clamitans melanota). Green Frogs are easily identified by their rounded eardrum (called a tympanum), a fold of skin (the dorsolateral fold) extending partway down the body, and a green or yellow upper lip. Females have tympanums that are the same size as their eyes and white throats. Males have tympanums that are noticeably larger than their eyes and yellow throats. The overall color of the species varies; Green Frogs can be yellow, brown, green or combinations of these colors. The morning temperature was cool (low 50s F) so the frogs were not too active and very difficult to see among the vegetation.

Leopard Frog, “Green” Form

Leopard Frog, “Green” Form, Emmet Co., Michigan

Northern Leopard Frogs (Rana pipiens) proved to be common at Wilderness State Park and the population contained many color variations. As I reached the park after lunch, the frogs were active in the heat of the day. Leopard Frogs resemble Pickerel Frogs but the underside of the hindleg is white in Leopard Frogs and yellow or orange in Pickerel Frogs. Leopard Frogs have two rows of roundish, dark spots on their backs. These spots are sometimes banded in a lighter color. Leopard Frogs also often have a spot behind each eye.

Leopard Frog, “Brown” Form

Leopard Frog, “Brown” Form, Emmet Co., Michigan

I chased frogs for a few hours, getting many photos of empty sand or plain vegetation (and giving thanks that I was no longer shooting film!) but, finally, I obtained a few passable photographs.

On our way home we stopped at Diane’s Bog and found a Wood Frog (Rana sylvatica). This is a small frog—less than three inches long—with a dark mask, underlined in white, extending from the nose to the tympanum (remember the eardrum). It has a fold of skin partway down its side.

Wood Frog

Wood Frog, Oscoda Co., Michigan

When I left home for the weekend I was not thinking about frogs. I have learned that the best way to travel is to just go and keep an open mind to the possibilities. You never know what you can find if you just look.

You’ll be lichen this.

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Elegant Sunburst Lichen

Xanthoria elegans, Elegant Sunburst Lichen

I found a brilliant orange lichen last weekend along the north shore of Lake Huron. It’s Elegant Sunburst Lichen (Xanthoria elegans). Bird excrement provides the needed fertilizer and the lichen grows in spots under likely bird perches.

Lichens are composed of three elements: algae, fungus, and cyanobacteria. Trevor Goward, the noted lichenologist from British Columbia, once remarked, “Lichens are fungi that have discovered agriculture.” He believes that the fungus benefits the most in this relationship. About 800 species of lichens are recorded from Michigan.

Elegant Sunburst Lichen close-up

Xanthoria elegans, Elegant Sunburst Lichen
close-up

I know Elegant Sunburst Lichen for a different reason; this is the “space lichen.” The European Space Agency sent this lichen to the International Space Station and exposed it to the vacuum of space. After surviving for 18 months by drying up and going dormant, it began to grow when given water upon returning to Earth. These are tough little plants.