A short history of apples

This is a rewrite of a post from September 2015, during the first fall harvest of my “apple orchard” (four dwarf trees).

This is apple harvest time in Minnesota, home of the Honeycrisp variety of apples, so loved by everyone who has tried one.

honeycrisp apples-

My honeycrisp apple trees are so loaded with apples, the branches are bending down to the ground.

It seems to be a Fall for bumper crops of all types of apples, from crabapples to honeycrisp, judging from the loaded branches of the apple trees on my street.

apple tree-loaded with fruit

An apple tree loaded with fruit awaits harvest. Squirrels take one bite and spoil a perfect apple, and the deer finish them off when they fall to the ground. 

Originally native to Kazakhstan, this highly productive forest tree has spread around the globe, even though the original progenitor was a small, sour, shriveled fruit that probably was more often used for a fermented beverage than eating.  After all, its genus name is Malus which is Latin for “bad”, as in bad-tasting.

michael-pollan-apple-origin

Quote from Michael Pollan on the origin of apples in his book, The Botany of Desire

From Kazakhstan, the seeds of better-tasting and fleshier types of apples were dropped by traders along the Silk Road to Asia and to Europe, and eventually made their way to North America with the early colonists who planted apple orchards, spreading the apple genes throughout the northeast, and eventually throughout the U.S.

apple harvest-Kazakhstan

Apple harvest-Kazakhstan marketplace. At its center of origin, there are 56 species of the wild Malus species, only 30 of which have been semi- or wholly domesticated for apple production.

But apples, like humans, do not produce carbon copies of themselves in their seeds, so each seed in an apple is as different from another seed in that same apple or from another seed in an apple on the same tree, as children are different from each other and from their parents.  And this is where the human-apple tree mutualism becomes important in the spread of apples to every corner of the globe.

We humans perform much the same service that bees do in pollinating the apple’s flowers, by selective breeding for appealing varieties and then growing new trees of that variety from grafts merged onto hearty root stock.  In return, like the nectar and pollen the tree supplies to its pollinators, the apple tree repays its dispersers (animal and human alike) with crisp, sweet fruit that lasts several months when stored properly at cool temperatures.

What is it that makes apples so delicious and so appealing to us humans?

cross section of apple-

A cross section of a Honeycrisp apple (which I ate while writing this) shows the star-shaped endocarp housing the seeds. Each of the 5 chambers houses 1-2 seeds. The total number of seeds per apple (5-10) depends on the energy resources of the tree.

Around the star-shaped seed capsules are ten yellow-green dots that are the remnants of the flower stamens. The sepals (that surround the petals of the flower) are at one end of the apple, and the flower stem (now a fruit stem) is at the other. In between is the greatly expanded floral cup that grows up and around the ovary housing the soon-to-be seeds, and is filled with starch granules synthesized by the leaves over a summer’s worth of sunlight.  At the end of the summer as the skin takes on its rosy blush, those starch granules begin to break down to individual sugar molecules — and voila, sweet, juicy, crisp Fall apples are ready to be harvested.

honeycrisp apples

A sample of the harvest from just one of my dwarf honeycrisp trees. 

The Honeycrisp apple is an invention (!) of the University of Minnesota’s Agricultural Experiment Station Horticulture Research Center (quite a mouthful — pun intended).  As an experimental variety, it was almost cast aside because the tree was not cold tolerant and couldn’t survive Minnesota winters.  But the fruit was exceptionally pleasant, with large cells with stiff cell walls that stored great quantities of starch and water and a relatively thin skin that made biting into its crisp sweetness a gustatory delight.  Moving a few genes around to introduce cold heartiness made the next version of the Honeycrisp a winner — to markets and palates everywhere.

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!

Beautiful, but deceitful and poisonous!

What is beautiful, but deceitful and poisonous?  This blog usually focuses on things biological, so it must be an animal or a plant, and perhaps it could be either.  In this case it is the oleander shrub that fits that description.

Nerium oleander flowers

Beautiful pink flowers of the highly poisonous oleander 

Oleander is such a popular addition to roadside plantings and gardens that it now occurs world-wide in warm, wet Mediterranean type climates where its long-lasting profusion of white, pink, or red flowers brighten up the landscape.  It is remarkably drought-tolerant and protects itself from being munched by herbivores by sequestering toxic cardiac glycosides in its tissues, from its roots to the tips of its leaves.  No wonder it’s the dominant plant along freeways in California.

Large milkweed bug on Nerium oleander flowers

An indicator of oleander’s toxicity is the presence of insects, like the large milkweed bug, with warning coloration feeding on flower parts and seeds.

Oleander is, in fact, one of the more poisonous plants, but mammals, especially humans seem to be more sensitive to its toxins than birds.  However, folk tales about drifters during the Dust Bowl years dying from having stirred their stew with oleander twigs are probably false.

Clearly, oleander is beautiful and poisonous, but what about being deceitful?  How can a plant be deceitful?

Nerium oleander flowers

Oleander flowers are brightly colored, sometimes fragrant, with a central opening meant to entice pollinators to explore.

But oleander flowers produce no nectar, and thus there is no reward for pollinators to keep exploring the profusion of flowers on the plant.  It’s false advertising and deceptive on the part of the plant.  But does it work, that is, does enough pollination occur to allow seeds to be produced?

flowers and seed pods of Nerium oleander

How many flowers with no nectar reward will a pollinator visit before it gives up and moves on?

Apparently, insects that pollinated this oleander explored many of the flowers in a cluster, moving enough pollen to produce several seed pods.  But the number of seed pods on the entire plant is scanty.

flowers and seed pods of Nerium oleander

Only a single pod was produced in this group of flowers

The only good news for bee pollinators is that the lack of nectar in the flowers means they would not contaminate their honey with cardiac glycoside poisons.

Surrounded by granite

Nothing impresses you like hiking up to an immense wall of granite, and immediately feeling very small and insignificant in the greater scheme of earth’s history.

Cathedral lake, Sierra Nevada, CA

Entering a huge granite bowl from a flat meadow landscape, you stumble upon beautiful, pristine-looking Cathedral Lake.

Cathedral lake, Sierra Nevada, CA

Turning just slightly clockwise from the previous view brings the Lake into focus.

There is something pure and almost spiritual about being at high elevation (maybe it’s the lack of oxygen) surrounded by sheer, steep granite.  The landscape begs you to just stand in awe.  How long has it been here, how has it changed over time?  How many people have stood here and wondered?

Cathedral lake, Sierra Nevada, CA

Mirrored reflection of granite peaks makes the landscape, especially the granite, loom even larger.

Sunset at a sunrise Lake, Yosemite, CA

Changing light at sunset adds a new dimension to the granite landscape.

Sunset, Glen Aulen High Sierra Camp, Yosemite, CA

A vast landscape of rock that goes on forever…

alpenglow at moon rise on Cathedral Lake, Yosemite

Alpenglow at moon rise on Cathedral Lake, Yosemite

30 years of hiking in the Sierras

We started a family tradition back when elder daughter was 12, hiking for a week in the Sierra Nevada mountains of California.  Every year about the time of her birthday, we have embarked on another excursion into the wilderness, usually with family along.

High Sierra hike

Now elder daughter introduces her own kids to the scenic wonders of the Sierra back country.

This year, the 30th anniversary of the first trip, and about an equal number of such excursions (meaning we only missed a couple of years when we didn’t hike there), we hiked the High Sierra Camp loop around Cathedral peak from Tuolomne Meadows in Yosemite.

High Sierra hike

The Sierra meadows are very dry this year. Creeks coming down from the mountain peaks that we normally would rely on for water were dry and made the hike a little challenging this year.

We felt very fortunate to have clear, sunny, smoke-free weather, with gorgeous scenic vistas of sharp mountain peaks as we hiked the 30+ mile loop.

High Sierra hike

Cathedral peak (left) in the distance was the primary landmark of the trip, seen even from long distance.  The grandkids were really impressed with the scenery, and loved it when the trails finally flattened out to make for easy hiking.

High Sierra hike

The reward at the end of a hard day’s hike was wading/swimming in the creeks or lakes in the midst of an amazing landscape.

High Sierra hike, Cathedral lake

Our last morning at our Cathedral Lake campsite

Our last campsite, at Cathdral Lake, might be one of the prettiest of all the lakes we have visited over these past 30 years.

Sunrise, Cathedral Lake, High Sierra

Sunrise reflection at Cathedral Lake

(all photos by Chris Mickelson with his fantastic iPhone!).

A conservation success story

The bird show at the Minnesota Zoo is always a kid pleaser (for adults too, for that matter), with some very showy birds trained to fly very close to the audience’s heads.  Watching the birds perform is educational for those who know little about the unique abilities of our feathered friends, but there is often a deeper story attached to some of the individuals — as was the case for the Blue-throated Macaw that made a dramatic entrance to the stage from a hidden crevice.

Blue-throated Macaw-MN Zoo

Here it comes, flying in toward the audience, a blur of turquoise above and coppery orange below.

Blue-throated Macaw-MN Zoo

With an impressive wingspan of 3 feet and weighing 2-2.5 lb, this is one of the largest parrots in South America. 

Blue-throated Macaw-MN Zoo

The particular pattern of stripes in front of the eye is unique to each bird, making them individually recognizable. Eye color changes with age, from brown in juveniles to gray, then white, and finally yellow in mature adults, making it possible to age the birds as well.

Like the much larger Hyacinth Macaw, the largest parrot in the world, these macaws have very long tail feathers, which makes their total body length from top of the head to tip of their tail a little over 3 feet.

Blue-throated Macaw-MN Zoo

Long tail feathers are a hazard in forest-dwelling birds. Perfect feathers like the ones on this bird are a testament to the excellent husbandry of these captive birds at the Zoo.

You might expect that exotic tail feathers like these would get noticed, even coveted, for some special ceremonial practices among indigenous people.  And that in fact, is one of the reasons that these very large parrots have become so rare in the wild, as they were once killed to make the fancy headdresses used in rituals and festive gatherings.  One headdress made from 30 of the longest tail feathers of the macaws (usually only the two central tail feathers are used) would require killing 15 macaws.

Indio-Paresi - Rodrigo Ono-

Ceremonial headdresses like this one most likely made from parrot feathers are common in indigenous groups throughout the Amazon basin and its tributaries.  Photo by Rodrigo Ono.

Like a variety of other tropical species, Blue-throated Macaw populations have suffered drastically from habitat loss, especially of their favorite nesting trees as well as the fruit and nuts they depended on for food, and from collection of young birds for the pet trade.  In fact, there are many more of these birds in captivity today than are living in the wild in remote locations in Bolivia where they are critically endangered.

However, trapping of Blue-throated Macaws has been illegal since 1986, and recent efforts to provide additional nest sites with artificial boxes has helped the small population of a hundred or so birds to recover slightly.  The most important conservation measure may be the promotion of the use of life-like, artificial feathers in the construction of native headdresses.  Not only does this save the birds, but it has become a great attraction for tourists, who want an authentic headdress to take home with them.

headpiece-Moxeno Indians_wendy_willis

A Moxeno Indian headdress made from artificial feathers. Photo by Wendy Willis.

headpiece-Moxeno Indians_wendy_willis

Better to see those beautiful tail feathers on the bird than on the headdress.

Jumping for joy?

When visiting the Minnesota Zoo with the grandkids the other day, I was fascinated with what was going on in the Dhole (pronounced with a silent “h”), or Asiatic wild dog pen. What I think might have been the male Dhole was doing a jump-dance step in one corner of his circuit around his pen.  It looked like this, but had no vocalization with it.

Dhole, Asian dog

Dhole, Asian dog

Dhole, Asian dog

Dhole, Asian dog

The jump-dance step was repeated several times, so it might have been part of a display for the female in the pen, or it might have been some type of aberrant displacement behavior, an artifact of being bored in its captive environment.

Dhole, Asian dog

Was he showing off for his mate?

Dhole (Cuon alpinus) are native to central, south, and Southeast Asia, but are not members of the familiar Canis genus that includes domesticated dogs, coyotes, wolves, African jackals, and even Australian dingoes.  They have shorter legs, different dentition, and differences in skull anatomy that distinguish them from members of the dog genus.

Dhole, Asian dog

Dhole are highly social animals, living in large clans of related individuals, but they lack the strong social hierarchy of wolves. They are typically diurnal hunters, going after medium and large-sized hoofed mammals and their young. Small groups of 3-5 individuals hunt cooperatively to bring down their much larger prey, much like African hunting dogs do. Although Dhole seem docile and non-aggressive in their clan in the wild, efforts to tame them have failed, as captive youngsters have remained shy or become vicious to handlers.  Dhole — an interesting dog “cousin”.

Wolfishness

Wolves doing what they do best at the Minnesota Zoo…enhanced for dramatic effect with a little photo editing.

Gray wolf, Minnesota Zoo

My attempt to make this very handsome gray wolf in its semi-natural Zoo enclosure look every bit of the dominant animal that it is.

Gray wolves, Minnesota Zoo

Wolffish greeting. I didn’t realize that wolves have such long thin legs, more apparent in their summer fur.

Gray wolves, Minnesota Zoo

The social hierarchy seems to be well established in this small pack: subordinate animals lower their heads in the presence of more dominant animals.

Gray wolf, Minnesota Zoo

the “leader of the pack”…

Continue reading

Roadside gardens

Quite a few years ago now, the city decided our street needed a walking trail, not just a mere sidewalk, along the roadside.  As a consequence, residences lost 10-20 feet of their front yards, and some embellishments like granite boulders or brick walls were added to separate hillsides from walking trails.  Somehow this spurred a roadside gardening movement, and the result is a long boulevard of very attractive gardens which have become a mecca for bees and butterflies.

Roadside garden

Monarch butterfly on Shasta daisy

A female monarch butterfly visiting a patch of Shasta daisy, but there is milkweed nearby as well.

Roadside garden

Daylillies of all colors brighten up the roadside.

Roadside garden

A profusion of pink and purple…

Roadside garden

Hoverflies love the pollen of these Asiatic lillies

Roadside garden

Thank you roadside gardeners for brightening up my morning walk!