Mulberries: Winter Observation, Summer Picking

During a recent winter walk in Eliza Howell Park, I stopped by some of the clusters of Mulberry trees that I visit in late June and early July, picking container in hand. Winter provides a good opportunity to note where and how they grow.

In Eliza Howell, almost all the Mulberry trees are found at the base of large trees that grow within the road loop. How close these trees grow to one another and to the larger tree is most evident in the winter when the leaves are off the branches.

I thought of the nursery rhyme (“All around the mulberry bush the monkey chased the weasel”) when I noted how completely mulberry trees surround the trunk of one cottonwood tree. If I were more clever or creative, I might try to complete a line that begins with “all around the cottonwood tree….”

Many mulberries are about 20 feet tall and, in their position under the taller trees, their branches spread and hang quite low. A lot of berries can be reached while standing on the ground. They progress from white to red to black, at which point they are ripe and ready.

Birds like mulberries, as do bird watchers.

A comment I have heard from individuals who have come upon mulberries for the first time is “they look like blackberries.” They do have a similar shape, but they grow on trees (blackberries grow on vines), and the fruit stems are very different. The taste is also different, of course, but that is best experienced by eating newly picked berries.

There are three different black-colored edible summer berries in Eliza Howell Park: Mulberry, Black Raspberry, Blackberry (in the order in which they ripen). Black raspberry also grows on vines.

In this collage, Mulberry is on the left, Blackberry is top right, and Black Raspberry is bottom right.

In my opinion, these three berries are the best foods to be harvested in Eliza Howell Park.

The first mulberry picking is at least 5 months away, but it is not too early to review the number and location of the trees. They may look to some like unwanted shrubs growing under larger trees, but they are worth getting to know.

Winter is also a good time to enjoy one of the results of summer picking. 

Jam made by Margaret Weber

A Favorite Pin Oak Tree: 19th Century Origins

The Pin Oak tree at the edge of the road in Eliza Howell Park is one of my favorite trees. It stands alone, with enough room for its branches to spread. 

At this time of the year, the leaves are fallen and the branches are bare.

I first started paying close attention to this oak because the birds are attracted to it. Warbling Vireos have nested here twice in recent springs and both Red-bellied Woodpeckers and Blue Jays are all over it in late September and early October, collecting acorns.

Photo by Margaret Weber

This is a quite large – and old – Pin Oak, a species that does not live as long as some other oaks. After having been asked several times how old it is, I decided to try to find the answer. There is no exact method of knowing the age of a living tree, but there is a widely used method of estimating the age.

The steps in estimating tree age are these:

1. Measure the circumference of the tree at 4 ½ feet from the ground.
2. Divide the circumference by pi (3.14) to get the diameter.
3. Multiply the diameter (in inches) by the “growth factor” that has been identified for the specific species, based on how fast growing it is. (Different organizations have published the growth factors for different species.)
4. The resulting number is the approximate age of the tree, in years.

Pin Oaks are moderately fast growing and have been given a growth factor of 3.0.

It is difficult to measure the circumference of a large tree by oneself so recently, when accompanied by Charon, another Eliza Howell enthusiast, we undertook the measurement.

At 4 ½ feet high, the tree measured exactly 12 feet in diameter (144 inches).

144 divided by 3.14 = 45.86.

45.86 times 3.0 = 137.58

Using this method to estimate age, the tree is about 137 or 138 years old.

137 years ago was 1883. This is just an estimate, but it is probably safe to say that this tree began to grow before the twentieth century, long before this property was donated to Detroit for parkland.

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It was already over 100 years old when I started enjoying it, appreciating it in all seasons. On hot summer days, when someone else has not claimed the spot, I park the car in its welcome shade as I take my walk.

Across the road is the prairie flower field and the Pin Oak sometimes makes a lovely background for a flower picture — Joe Pye Weed in this case.

Pin Oak leaves turn late in the Fall, in November in Eliza Howell. The bronze (?) shade is not as striking as the leaves on some other trees, but there is something very attractive about it.

As oak trees go, Pin Oak trees do not have a long lifespan. This one is perhaps older than average. I hope it continues to provide beauty, food, shade, and nesting habitat long after my nature walk days are over.

The Oil Beetles of Eliza Howell Park

I see Oil Beetles — large, dark, metallic-looking beetles – in Eliza Howell Park only in October and November. They are not particularly photogenic or otherwise likely to catch someone’s attention, but their story is part of the fascinating natural world that exists right here in the neighborhood.

I last saw one in 2019 on November 25, as it and I were walking on the park road.

Oil Beetles, a type of Blister Beetle, are nearly an inch long and, when I see them, are walking slowly on the ground in or near the fields in the park. My earliest 2019 observation was on October 17 (next picture). They are not numerous; even in their “season” I do not see them on every visit.

Oil Beetles are flightless. The adults emerge in the Fall and proceed in their slow and somewhat cumbersome walk toward a good place to winter in the soil. Based on the published research I have consulted, I think the female lays eggs in the spring, but I have seen them mating in the Fall. This pair was photographed in early November.

They are called “Oil” Beetles because, like other Blister Beetles, they can secrete oily droplets from their leg joints when threatened. This “oil” contains a toxic chemical (cantharidin) that can cause painful blisters on human skin.

They have no hind wings and the short front wings cover only a small part of the large abdomen.

Some Oil Beetles spend the immature phases of life in parasitic fashion in the nests of ground-nesting bees, eating the food that is brought in for bee larvae. 

There is much I don’t know about these beetles, but they now have my attention. I am sure that I will think of Oil Beetles when I next see ground-nesting bees.

 

Beaver!

For the first time in the years that I have been engaged in nature study in Eliza Howell Park, I am now seeing signs of beaver activity. There are some 20 small trees near the river (the largest are about 4 inches in diameter) that have recently been cut down and removed.

Beaver were an important part of Michigan’s history; the pursuit of their pelts was a major factor in the movement of Europeans into this part of the country. Unlimited trapping resulted in their being extirpated from this area some 150 years ago.

Some are now returning. In the last decade, they have been found along the Detroit River (including on Belle Isle) and a few have appeared in the Rouge River system. Until now, to my knowledge, none has been reported this far upstream on the Main branch of the Rouge.

I have not yet actually seen a beaver in the park (they are largely nocturnal), but I know of nothing else that cuts down trees and leaves these teeth marks.

Young beaver stay with their parents until 2 years old or so, when they leave to find a mate and establish their own lodge and colony. Perhaps the signs of beaver activity in Eliza Howell mean that a new pair is taking up residence here, for the first time since long before this area was established as a park.

There is a lot I do not know about beaver from personal observation. They were not in the various areas I have walked regularly during my life and my observations of them when visiting other locations were limited. There is much for me to learn.

While most descriptions of beaver lodges are of conical lodges in a pond formed by a dam, they also make lodges in banks, with under water entrances, especially along rivers where the water is deep enough for them to swim under water/ice. The water level in the Rouge in the park varies throughout the year and I do not know whether it sufficiently deep to meet beaver needs. This is what it looked like on my last visit in the area where the beaver had cut trees.

If they stay here, my guess is that they will be “bank beaver,” but one of the things I will be watching to see is whether they act to raise the water level, perhaps by using a current logjam as the start of a dam.

Beaver are able to change the environment in which they live and this has sometimes led to them being considered by some as a nuisance or a pest (for example, when their dams lead to flooded roads). Their overall impact on ecosystems and on sustainability has, however, been viewed by most researchers as very positive, as evidenced in a widely-endorsed, and very readable, book published last year.

I will also be looking for additional signs of their presence and of their behavior. So far I have not seen clear tracks in the mud, perhaps because most of the mud along the river is currently covered with leaves. The hind track (webbed) is reported to be about 6 inches long and the front about 3 inches. These drawings are from The Peterson Guide to Animal Tracks.

I cannot say definitely that beaver have taken up residence in Eliza Howell Park, but I will now have a different answer when asked whether any beaver live here.

I have been saying “not yet,” hoping that they would show up one of these years. Now I can say “there are definite signs; let me show you.” Perhaps soon I will be able to give an unqualified “yes.”

Oriental Bittersweet: November Fruit

When the bright red and gold leaves of the Fall have fallen by the middle of November, there remains another red and gold attraction in Eliza Howell Park: the fruit of the Oriental Bittersweet.

Though there are still a few remaining honeysuckle berries that the birds have not quite finished, bittersweet can be considered the last fruit of the season. As recently as September, it showed little indication of the starring role it would later play.

Oriental Bittersweet is a vine that was brought to this country in the 1800s and has now spread widely. There is also a native North American Bittersweet vine, but the ones that I watch in Eliza Howell are the Oriental variety. It grows and spreads rapidly and can climb dozens of feet. The next picture shows the twinning nature of the vine; the following one gives an indication of its ability to climb trees.

The outer seed covering totally hides the fruit inside until late Fall. Birds are not attracted until the outer shells begin to open, allowing access to the red fruit, usually after the bittersweet leaves have already fallen. 

The gold shell, which opens in three parts, remains attached for a time (contributing to the attractive red and gold look) and later drops to the ground. The red fruit may hang on well into winter.

Though Oriental Bittersweet might make for an attractive home decoration at this time of the year, people are rightly advised not to pick and transfer. Unless the seeds are very carefully disposed of, new plants could sprout, spreading the aggressive and hard-to-control vine. It is considered an invasive plant that may damage the environment.

The word “bittersweet” means pleasure accompanied by some negative feelings, sweet with a bitter aftertaste. The pleasure of seeing the red and gold fruit of Oriental Bittersweet can indeed be a bittersweet experience.

 

The River, the Season, the Weather: Tracking Fall 2019

I often stop on the footbridge during my walks in Eliza Howell Park, stop and take a picture, looking upstream the Main branch of the Rouge River. These pictures help me track seasonal changes and fluctuations in water level.

Below are 8 photos taken on different days during the four weeks from October 16 to November 13, 2019. Some from sunny days and some from cloudy days, these pictures presdent the progress of Fall this year.

October 16, 2019  (9:47 a.m.   Approximately 50 degrees F)

October 20, 2019 (3:04 p.m.   Approximately 60 degrees F)

October 24, 2019  (11:23 a.m.  Approximately 50 degrees F)

October 27, 2019   (11:57 a.m.  Approximately 45 degrees F)

November 1, 2019   (9:31 a.m.   Approximately 35 degrees F)

November 4, 2019   (10:22 a.m.   Approximately 45 degrees F)

November 8, 2019   (10:07 a.m.   Approximately 25 degrees F)

November 13, 2019   (10:52 a.m.   Approximately 15 degrees)

The changes from the middle of October to the middle of November, always dramatic along the river in Eliza Howell Park, were even more dramatic this year because of the unusually heavy snow of November 11.

 

Kentucky Coffeetree: Watching Seed Pods

Since August, I have been checking regularly two Kentucky Coffeetrees that grow in Detroit’s Eliza Howell Park, paying them much more attention than I have in other years. My main interest has been the developing seed pods.

These pictures were taken in August.

Kentucky Coffeetree is a tree native to, though not very common in, parts of the mid-west. Southern Michigan is at the northern end of its original range. It is now sold by nurseries and used as a landscaping tree. The size and location of the Eliza Howell trees suggest that they were planted here long after the park was established. They are both female trees, producing seeds.

The seeds (beans) of the tree have been used – roasted – as a food in some Native American cultures and the Meskwaki (Fox) are said to have ground them for use in a hot beverage. Early European colonists also tried it as a “coffee” as well. (Unroasted pods and seeds are reportedly toxic.)

The seeds mature slowly. When the leaves began to turn in October, the pods were darker in color, but remained firmly attached.

The pods vary in length, most about 4 or 5 inches long, much shorter but thicker than the pods of the Honey Locus tree, often seen on the ground at this time of the year. I placed the two together for comparison.

Now, in early November, the Coffeetree leaves are down. But the seeds remain firmly on the tree; I have not yet found a single one that has fallen on its own. (I picked those that I have examined.)

This picture was taken this week.

The pods are not yet as tough as they will get and the seeds, though considerably changed since August, are not yet fully mature.

I sometimes refer to my visits to Eliza Howell as “doing research.” It sounds more serious than “going for a walk.” One of my current research questions is: “When will the Kentucky Coffeetree seed pods fall?” My hypothesis is that it will not be for at least another month.

It’s an exciting life I lead – watching seeds mature!

 

 

The Amazing Queen Hornet

In the early 1950’s, my siblings and I sometimes listened to the radio crime-fighting drama, The Green Hornet. That was then. Now the hornet I am thinking of is the Queen Hornet.

November is the best month of see Bald-faced Hornet nests in Eliza Howell Park. I walked past some of these nests many times during the last several months, but they were so well hidden in the (often maple) leaves that, despite their larger-than-football size, I found them only after leaves have fallen.

The number of different hornet nests I see in the park varies from year to year. This year it was only 7 (so far), compared with about twice that many in each of the last two years. The winter of 2017-18 was colder than the previous two years, which is the likely explanation for the decline.

The nests I am now finding are finished; they no longer contain living hornets. Fortunately, I did find an active nest in August, low enough in a tree for me to approach and photograph. I was, of course, conscious of the need to approach carefully; “worker” hornets will sting repeatedly to protect the colonies.

The white on the face accounts for the “bald-faced” name. They are also sometimes called “White-faced Hornets.”

As I was taking close-ups, trying to be very quiet and deliberate, all went well until I accidently touched a twig on the tree. The vibration brought out some 10 – 12 defenders that buzzed around looking for the problem. I stood perfectly still and they eventually returned to the nest, apparently not identifying me as a threat. I went my way unstung.

The nests began about 5 months ago, started by a queen. At the end of the season, the inseminated new queens are the only survivors from the colony. A new queen leaves the nest and finds a location (such as under bark or rotting wood) to hibernate. In the spring, if she survives the winter, she will start a new nest all by herself.

Earlier this month, during a Wild Indigo Detroit field trip to Eliza Howell, someone turned over a rotten log to observe the life hidden there. One insect found was a Bald-faced Hornet. The location and time of the year suggested that it was a queen, though she was very sluggish and not very regal appearing.

In the spring, a surviving queen selects a location, usually in a tree, and starts a new nest, using wood fiber. The nest is small at first but big enough for her to begin laying eggs. The first new hornets of the year are sterile females (the “workers”) who then take over nest building and raising young. The queen has the responsibility of producing more offspring. Typically, a mature colony has over 100 hornets.

Now that the season is over, there is often an opportunity to take a look at the structure of the nest, the home of a whole colony for one brief season.

Since the nests that we can now find are no longer maintained and birds often open them searching for food, they will soon fall. They remind me of the life they supported in the summer.

These empty nests also remind me of the amazing queen, hibernating in some hidden and sheltered spot, capable of starting a whole new colony by herself.

A November Walk: Reflections

Walking in the woods of Eliza Howell Park recently, I was noting how far advanced the trees are in acquiring their winter bare-branches look. It is November and trees are becoming dormant for the winter.

Walking in the woods alone can be a time for reflection. As I approached the log of a tree that had fallen at least 10 years ago (one that I have watched slowly returning to earth over that decade), I focused on the fact that trees not only go dormant for the winter but they also die. Over the 14 years that this park has been my nature study area, I have seen many trees die and fall.

The tree in the next picture fell fairly recently and is now beginning to decompose.

Long-lived species can live many years, but they do die. Perhaps we could say that they reach the November of their lives when they about 5/6 of their life expectancy.

Perhaps this maple is in the November of its life?

If we were to live to be 90 (a long life), 75 is the beginning of our November. This would put me in the November of my life.

Humans are a long-lived species, but we have a limited lifetime. While we do not live indefinitely, life goes on. As we age, many of us think of the legacy, the contribution to future generations, we are leaving.

In another location in Eliza Howell Park, there is a young tree growing out of a rotting stump, a new tree of a different species from the stump.

This might be a good image to reflect upon in terms of the legacy that we can leave: a place for others to grow and thrive, whoever they may be.

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There is much to be observed and learned on nature walks in Eliza Howell Park. At times, this leads to reflections about our own lives. This is one such occasion.

Surviving the Winter? The Praying Mantis

This is a follow-up to the posting on September 13 this year – “Praying Mantis Egg Laying.”

Adult Praying Mantises do not live beyond the fall; the next generation is in the egg cases and will emerge in the spring. They will emerge if all goes well. Since September, I have been checking on egg cases in Eliza Howell Park.

My observations began on September 5, when I watched two different females lay their eggs. This is what the fresh new egg cases looked like then.

That same day, I noticed a pair mating so was confident that those two egg cases would not be the only ones this year.

In the weeks that followed, I many times walked the narrow path through the field of wild flowers and small shrubs/trees. I gradually saw more and more egg cases, especially when they became easier to see after the leaves dropped. These five were found in early November.

As of now, I have located 11 different egg cases visible from that path. Almost all of them are on the small trees (buckthorn, for the most part) growing in the field. Since each egg case probably has dozens and dozens of eggs, 11 cases would suggest a large number of little mantises emerging in the spring. If all goes well.

Some of the birds that spend the winter in the park are insect eaters, birds that often seek insect eggs and larvae. Praying Mantis eggs, though protected in the oothecal, are vulnerable to birds with beaks that probe.

Recently, I have been seeing evidence of predation.

Of the 11 egg cases I am aware of, 6 have been opened like this. And it is only November. The number of Praying Mantises estimated to emerge in the spring in Eliza Howell is decreasing rapidly.

While I have not directly observed this, I suspect that Downy Woodpeckers are responsible for invading these egg cases. Insect eggs are a part of their diet and they frequently forage on small trees and on plant stalks.

Photo by Margaret Weber

Another threat to the survival through the winter is the weather. One of the eggs cases is on a goldenrod, a large perennial that typically does not stay standing all winter. Last week, during the first snowfall of the year, it was bent low by the heavy snow, but it came right back up when the snow melted. The first picture below is from November 9; the second from November 10.

The stem will get weaker as the season – and the snow — continues. I do not know how well developing Praying Mantises are likely to do when an egg case ends up on the ground, but there is a reason why they are placed off the ground when the eggs are laid.

We know that only a very tiny percentage of acorns sprout. In July, I reported that very few, if any, of the toad eggs laid in the breeding pond left the pond as toadlets this year. It should not be a surprise if only a small percentage of Praying Mantis eggs laid this fall will result in live mantises in the spring of 2019.