The island of Prince Edward

We aren’t seeing it at its best, on a cold, rainy, foggy day, but in 1864 tiny Prince Edward Island was the birthplace of the Confederation of Provinces that make up Canada.  It has the least amount of wild nature remaining of any of the provinces, and it grows 1/3 of the potato crop of Canada, but its primary claim to fame is as home to fictional Anne of Green Gables.  On a sunny day, biking through the pastoral landscape on the Confederation Trail would have been ideal.  Instead we tried to escape the rain by following a forest path through Victoria Park at the western end of Charlottetown.

Charlottetown. P.E.I. shoreline

The shoreline in Charlottetown, Prince Edward Island

Charlottetown. P.E.I. shoreline

Not a lovely day at the shore, even the Herring Gulls look depressed.  So much fog, you can’t see across this small bay.

Victoria park, Charlottetown, P.E.I.

There is a mature beech, sugar maple, basswood forest in Victoria Park.

Large basswood tree, Victoria Park, Charlottetown. P.E.I.

An island surrounded by water has a moderated climate. The leaves haven’t started changing here yet, although the huge basswood has already dropped its leaves.

Black-capped Chickadee on Prince Edward Island are bigger than usual

Black-capped Chickadees on Prince Edward Island seem bigger than usual, by about 50%, more the size of a White-breasted Nuthatch.  In addition, they have pinky brown feathers below their wings.  Island races often differ from their mainland counterparts, developing in isolation over generations.

Fall harvest decoration, Prince Edward Island

Fall harvest decorations are also common in Charlottetown, like they were in Quebec City.

Fall harvest gone wild

This should be called the year of the fantastic nut crop: acorns by the ton, walnuts carpeting the lawn, and buckeyes remaining unharvested because there is a food surplus in the backyard like never before.

Ohio buckeye nuts

The Ohio Buckeye tree is loaded with nuts, which the squirrels should have harvested by now.

Why is this happening?  I don’t remember there being great spring weather; oh wait, I was in the UK during spring.  The summer was the usual blend of hot and humid interspersed with cold and rainy, so it must have been perfect for growing a huge nut crop.  But why have all the oak trees in the backyard gone crazy with acorn production?

Oak acorns

The forest floor has become crunchy with fallen acorns. This is just what the squirrels leave behind.

We are experiencing a “mast year” in oak tree production of acorns, which happens irregularly, every two to five to seven years.  And it’s happening in not just one species of oak, but simultaneously in the three most common Minnesota oak species — the northern pin oak, the northern red oak, and the bur oak.

Bucks eating acorns, photo by Charles Alsheimer

In a normal year of acorn production, animals consume or store most of the acorn crop, leaving little chance that the nuts could sprout into seedling oaks. Photo by Charles Alsheimer.

In a recent post (September 12), I discussed how trees “talk” to each other, and this synchronous boom production of acorns is a good example of the result of that communication, which can occur not only locally within a forest, but over broad distances.  Basically, mast production of acorns is the trees’ combined strategy of satiating the acorn consumers so that the leftovers can develop into seedlings.

The oaks must have been talking to the walnuts in the backyard as well, and the squirrels are just not able to keep up with the bounties of this fall harvest.

Gray squirrel husking a walnut

Bring all your friends, Mr. Squirrel, I’ve already raked up a garbage can full of walnuts.

The perfect response to this enormous fall bounty — “stop, I’m full already”.

National Geographic funny animal photos, 2018, Photo by Mary McGowan, CWPA, Barcroft Images

National Geographic funny animal photos, 2018, Photo by Mary McGowan, CWPA, Barcroft Images.

Can trees talk to each other?

How do trees talk to each other

Is this artists’ conception of tree communication real?  https://albertonrecord.co.za/182186/enviro-monday-trees-talk-via-wood-wide-web/

My apple trees are well synchronized with each other, so I have bumper crops of all 4 trees in alternate years.  Of course I want them to flower at the same time, so there is ample pollen for cross pollination of the different varieties.  However, this year, the trees were unusually productive…

Apple tree fruit production

There are hundreds of apples on my 4 trees, much more than can fit into my canning jars and refrigerator for long term storage.

Honeycrisp apples

Honeycrisp apples are reaching maximum ripeness, and attract passers by as well as the squirrels, birds, and deer that wander by for a sample.

Is it just coincidence that these trees are so well synchronized or do they somehow communicate with each other about their status?  A quick google search led me to a terrific article in Smithsonian magazine from March 2018 on this very question.

One way that trees, and plants in general, can communicate with each other is by way of the mutualistic fungi that entwine their combined roots.

How do trees talk to each other

Exchange of sugar (Carbon) and nutrients between fungi and roots and between trees.  https://albertonrecord.co.za/182186/enviro-monday-trees-talk-via-wood-wide-web/

The fungal strands search out and transport various nutrients that the plants need (nitrogen, calcium, phosphorus, magnesium, etc.) from the soil to the rootlets, and the trees pass photosynthesized sugars from the rootlets to the fungi in a very cooperative relationship.  But it goes beyond just the interaction between plant and fungi.

Research by Suzanne Simard (in a very interesting TED talk) has shown that individual trees in the forest are connected in a dense underground web of overlapping and intermingling roots and fungal associations, and this web consists not only of a “mother tree” and its seedlings, but trees of all ages of other species as well. Through these connections trees exchange carbon and other nutrients, paying a small tax to the fungi along the way.

Web of connection between forest trees, Beiler et al. 2010

A diagram of potential connections of forest trees (Beiler et al. 2010).  Large dark green circles are the busiest hubs (mother trees), sending carbon to other smaller trees, as well as their own seedlings (yellow dots) which may be growing in deep shade.

Not only are trees sharing resources in this busy underground network, but they are communicating with each other through secretion of plant hormones and volatile secondary compounds as well.  For example, Giraffes that munch on the leaves of one acacia tree will stimulate the production of distasteful tannins not only in the other leaves of that tree, but in its acacia neighbors as well.  In fact giraffes have learned to forage on the acacias that are downwind in a clump of trees to avoid this kind of response to the volatile chemicals released by the injured tree.

oak forest, Berkeley botanical garden, CA

Oak trees also produce chemical messages when under attack from herbivores, so that nearby oaks get a head start on ramping up tannin content of their leaves. I might have enhanced the “face” on the mother tree a little.  Photo from the Berkeley Botanical Garden, in a Backyard Biology post on Magical Oak Forests.

This kind of changes the way we look at forests, or even small patches of prairie, or garden plants, or shrubs growing together in our backyards.  These plants aren’t as much competitors as they are collaborators, existing side by side, in a mutual quest for light, water, and nutrients.  We could learn a lot from plants about cooperative existence!

A walk in the forest

Rothiemurchas forest in the Cairngorm National Park of Scotland was once the center of the great 12th century Caledonian pine forest, and some of its patriarchal trees may still stand.

Old Scotch pine, Grantown-on-Spey, Scotland

Rothiemurchas forest near Aviemore has some of the oldest and largest Scotch pine in the U.K.  

We found some new (to us) birds here, as well as some familiar ones, but one of the surprises was all the red squirrels in this part of the forest. They are about the size of the North American gray squirrel, but with much bushier tails, and ear tufts. In many places these native squirrels have been displaced by the introduced gray squirrels.

Red squirrel, ScotlandRed squirrel, Scotland

Rothiemurchas forest near Grantown-on-Spey, Scotland

The forest here is a mixture of very young and very old pine, along with dense stands of birch, and remarkably little undergrowth.

Although most of the birds were found high in the tree tops, a few cooperated by flying in close.

Coal tit

Coal tits are close to the same size as Black-capped Chickadees, and resemble them in looks and behavior.

Siskin, Scotland

European Siskin look like a combination of American Goldfinch and Pine Siskin. The males are bright yellow, with paler females that look very much like the American Siskin.

Ewe and lambs, Scotland

This is lambing season in Scotland. Twins scamper over to their dams for reassurance and a drink when we get near to take their photos.

the amazing California Bay

The California Bay tree, also known as the California Bay Laurel or California Laurel, and a host of other names, is one of its kind, the only species in its own genus, and quite an interesting plant.  Bay trees are part of the coastal forest and unique to the California floristic province.

Huckleberry Botanical preserve, Oakland CA

Mixed oak-bay coastal forest at Huckleberry Botanical preserve in the Oakland hills.

Their leaves are more pungent than the Mediterranean bay used in cooking. My husband once stuffed a chicken with bay laurel leaves before cooking it on a Boy Scout camping trip and found it completely inedible.

Like some other coastal tree species, California bay have a swollen base of root crown called lignotuber which protects delicate buds that sprout when the central trunk has been damaged.

Stump sprouts in California bay laurel

Stump sprouts in California bay laurel shoot upward from the root crown.

The resultant growth of multiple stems emerging from the root crown makes this forest look like a dense jungle.

California Bay Laurel

Atypical growth form of the California is bay tree, where numerous sprouts have replaced the central stump that might have been damaged by fire or storm.

multiple stems of California bay laurel

Multiple stems of California bay laurel tower over the fern understory on the banks of a small creek.

California Live Oak, Huckleberry Botanical Preserve, Oakland CA

On the more southern-facing (I.e., sunnier and drier) side of the creek, the trees are predominantly California Live Oak, with noticeably fewer laurels and no fern understory.

What a difference the microclimate of this forest makes.  We wore our jackets while hiking through the dark, shady north facing laurel forest, and worked up a sweat climbing the sun-exposed hills of oak forest.

Mixed hardwood-coniferous forest at Huckleberry Botanical Preserve, Oakland CA

Mixed hardwood-coniferous forest in the Huckleberry Botanical Preserve is truly impressive.

color me beautiful

The Amur Maple forest has once again reached its full fall splendor.

amur-maple-forest-

The introduced Amur Maple is really more of a tall shrub, but it grows so densely along the roadside it forms an almost impenetrable forest.

Dense thickets of Amur Maple crowd out and shade out natives that might grow there —  really the only thing this species has going for it (in my opinion) is the brilliant color display of its fall leaves.  The ground cover beneath the trees looks like a collection of fallen leaves, but on closer inspection, it seems to be a mini-forest of Amur Maple seedlings, ready to bolt up as soon as a light gap appears in the forest overhead.

fall color - Amur Maple-

Bare branches above, lots of colorful leaves on the ground — right?

fall color - Amur Maple-

There are some fallen leaves here, but there are more tiny seedlings, each with just a few leaves, carpeting the ground and leaving no bare areas for anything else to invade.

fall color - Amur Maple-

It’s a very photogenic forest, and easy to walk through since there is no understory.

fall color - Amur Maple-

The birch in the background established itself first here, but the Amur Maple seedlings beneath the birch will make it impossible for birch seedlings to get established.

fall color - Amur Maple-

but what color!

fall color - Amur Maple forest

Another glorious Indian Summer day

colorful rivers

Well, not so much the color of the river per se, but it was the color along the river last week in Wisconsin and Michigan during the peak of the fall color show that was impressive.  Some examples, seen between rain showers:

wolf river, wisconsin-

Along the Wolf River on the way to Rhinelander, Wisconsin, the sumac is intensely red, and maples have turned a brilliant yellow, orange, or red.

Wolf River, Wisconsin

Places like this are where you wish you were in a canoe, drifting down a lazy part of the river, gazing at the glorious color along the shoreline.

wolf river, wisconsin-

Not a huge waterfall by Lake Superior north shore standards, but a pretty scene nonetheless.

We know that warm days and cool nights of fall stimulate plants to break down their chlorophyll, unmasking all the xanthophyll and carotene photo pigments in the leaves, and those changes in leaf metabolism produce the yellow, orange, and red colors.  I have written more about the chemistry of leaf color change earlier — (“you know it’s fall when…”).  But what accounts for the synchronous color changes of rural northern hardwood forests, compared to the more prolonged sequential color changes we see in urban landscapes?

Summit peak, Porcupine Mts, Michigan

Synchronous color change in mature beech-maple hardwood forest, Porcupine Mts., Michigan.  You don’t see sights like this in many urban areas.

Lots of factors might be responsible:  urban areas are generally warmer with a less homogeneous climate than surrounding open countryside; plants in a natural forest most likely respond to climatic changes in similar ways, whereas planted urban trees, often non-native, adapt to a mixture of environmental cues with different schedules for leaf fall.  Leaves might change color more slowly and stay on trees longer in the urban environment simply because temperature and moisture conditions there are so different from the surrounding countryside.

Fall color in the “Porkies”

I’ve always wanted to visit the Porcupine Mountains in northwestern Michigan, and fall is the perfect time to take in the color change in the forest, as well as the dramatic cliffs in the park.  Rising to a peak of just under 2,000 feet and lining the southeastern shore of Lake Superior, they provide great views of the most extensive old growth of northern hardwood forest west of the Adirondack forest in New York.

Lake Superior from Summit Peak, Porcupine Mts, Michigan

A view from the 75 foot observation tower at Summit Peak on the southern edge of this 31,000 acre park.  The climax forest of maple, basswood, yellow birch and hemlock stretch beyond what the eye can see. Lake Superior is in the far distance.

Observation tower at Lake Superior from Summit Peak, Porcupine Mts, Michigan

An extensive series of boardwalks, platforms, and an observation tower ensures great views of the forest landscape.

One of the star attractions of the park is Lake of the Clouds, so named for its mirror reflection of the sky. But equally impressive are the sheer cliffs of ancient volcanic rocks that form a long escarpment on the northern side of the park. These are the exposed remnants of the volcanic action that formed the mid-continent rift that runs from western Lake Superior all the way down to Kansas.

Lake of the Clouds, Porcupine Mts, Michigan

Lake of the Clouds, Porcupine Mts, Michigan

Outflow from the Lake of the Clouds also reflects some of the sky.

Lake of the Clouds, Porcupine Mts, Michigan

Glacial action has polished the surface of the volcanic rocks here, making them almost slippery.

On the western edge of the park, the Presque Isle river churns through volcanic deposits scrubbing out holes and undercutting cliffs.

Presque Isle river, Porcupine Mts., Michigan

The river is lined with hemlock forest where trees are so close together, barely any light makes it to the forest floor.

Hemlock forest, Presque Isle river, Procupine Mts., Michigan

Well-marked trails and wonderful scenery make this an exceptional place to visit, especially during the peak of the fall color season.

Ridges and Swales

It might sound like this is about a fashionable department store, but beach ridges and the shallow, watery swales between them are natural features of the Great Lakes shorelines. We hiked at one example of this complex ecosystem at the Ridges Sanctuary in Bailey’s Harbor on the eastern side of the Door peninsula.

The Ridges Sanctuary, Baileys Harbor, Door County, WI

The entrance walkway to the Sanctuary crossing over a swale, with the shoreline lighthouse at the end.

Ridges and swales are most likely to develop where coastal land is uplifted or where lake levels fall, which is probably what has been happening here in the past 10,000 years since the last glacial recession.  Sediments are deposited with gentle wave action against the shoreline in a protected harbor, leaving behind a low hill of sand and gravel in which hearty colonists establish themselves.

Map of The Ridges Sanctuary, Baileys Harbor, Door County, WI

Map of the Ridges Sanctuary, showing the parallel rows of beach ridges separated by low-lying wet swales.  Black lines are the trails through the area.

The Ridges Sanctuary, Baileys Harbor, Door County, WI

The most recent beach ridge on the shoreline is being colonized by 3-foot tall conifers and grasses, which will slowly add humus to the sandy matrix, improving conditions for further growth.

The Ridges Sanctuary, Baileys Harbor, Door County, WI

Between each of the Ridges, is a low, wet area (the swale) where sedges thrive, and assorted moisture-loving plants, like orchids thrive.

The Ridges Sanctuary, Baileys Harbor, Door County, WI

Raised walkways guide hikers across the swales and provide views of wildlife and exotic plant species along the edges of the ridges.

The variation in environment from dry to wet, or coastal to inland makes this an extremely diverse ecosystem, home to more than 500 species of plants, 60 some species of birds, and more than a dozen mammals.

Fringed Gentian, Ridges Sanctuary, Door County , WI

Fringed Gentian is one of the 500+ plant species to be found in this diverse ecosystem.  Summer blooms include at least 25 species of native orchids, along with bog species like pitcher plant and sundew.

Fringed Gentian, Ridges Sanctuary, Door County , WI

The Ridges Sanctuary, Baileys Harbor, Door County, WI

The ridge furthest from the coast begins to look more like mature coniferous forest, with tall red pine, white cedar, and fir trees. The path here is spongey, needle duff rather than sandy gravel.

The Ridges Sanctuary was founded in 1937, becoming Wisconsin’s first land trust, designed to protect the state’s most biologically diverse ecosystem.