The end of fall

We have been treated to more than two months of fall this year, so I have no complaints about the weather. But this last week marked the end of the color, as we now pass into the drab browns, grays, and soon white that will dominate the landscape until next spring. So, a few parting shots of the end of fall...taken along some of my favorite jogging routes.



An Amur Maple understory (this is an extremely fast-growing introduced maple (from Asia). At least they have very attractive fall foliage.

This mixed deciduous and pine forest was the view across a small stream.

And this was the view of the reflection of those trees in the very still stream water.

Sort of disorienting, isn't it?

And finally, the last tree to light up, even later than the oaks, must be the Norway Maples planted in residential areas. This is probably a horticultural variant of the tree that is native to central and eastern Europe and Asia. I only realized just how popular this tree is in residential gardens when they all simultaneously changed color during the past two weeks.

It has a very wide leaf with smoother and rounder edges than our native maples, and the leaves seem to be a very uniform solid yellow with very little orange or red in them. I assume that means they are full of xanthophyll (yellow) photo pigments which don't show until the chlorophyll has disappeared.

I'll certainly miss my colorful walks in the woods. Time to get out the snowshoes.

4 and 20 Blackbirds

Well, not only blackbirds, but grackles, descended in a large flock (maybe 100 birds), some concentrating on spilled seed on the ground, others attacking the feeders to displace even more seed onto the ground.

Males jockeyed for position on the feeders.

There was a noticeable pecking order: male grackles over male red-winged blackbirds, over lowly females of either species, who fed almost exclusively on the ground and in the wildflower garden. Grackles aggressively dominated the suet feeders and tried to fit their big wide bodies on the seed feeders desiged for chickadees.

Blackbirds have lost their glossy black exterior and are brown instead, resembling the female plumage, but still have their bright red and yellow wing patches, which they flare out when trying to displace another bird.

Grackles haven't lost any of their brilliant breeding colors, because they have iridescent feathers. There is quite a range of color on the males, from the brilliant light blue on their heads, to the deep purple on their backs, and brown on the sides. Getting pecked by that long saber of a bill must really hurt.

Male grackles were quite aggressive toward one another at the feeders, as well as the blackbirds, as illustrated below. It's clear who the top dog is.

Does this look like a scene from "the Birds"? It doesn't really capture the moment accurately because there were probably five times that many birds, and they were all squawking continuously.

Forming a huge flock like this in the fall is typical in migratory birds. They get the advantage of many eyes to find food and to detect and ward off predators, but with such a feeding hierarchy you wonder if the bottom of the pecking order really gets enough food to make the migration.

Cold Goldfinch

This has been the longest and nicest fall weather I can remember since we moved to Minnesota. But we now have reminders every morning of the cold weather on its way as the temperatures dip into the 30s overnight. I was surprised to find lethargic Goldfinches in the garden on two of these nippy mornings this week; they sat quietlly allowing me to approach within a few feet. Their plumage was so fluffed out they looked like little round puffballs.

I found this one sitting on the ground near the bird bath I was filling. Of course I didn't have a camera with me, but he/she was still there when I went back with the camera in hand.

Could those feathers get any more fluffy?

The bird appeared healthy enough, with its alert eyes following me as I walked around it. It moved into the sun a few minutes later, and then flew off into the weeds near the bird feeder.

Fall weather is hard on all us homeotherms, as we try to rev up the metabolism that keeps us warm. Acclimation to cold typically takes a few weeks as increased thyroid hormone helps us increase heat production and changes in blood flow to the skin reduce heat loss. Decreased hours of daylight here in the far north means less time for animals to fatten up during the day to fuel the metabolic furnace overnight. Maybe these little guys (they only weigh 12-15 grams, about the same as a fast food ketchup package) just run out of energy on those colder nights and need more time to rewarm during the morning. I know mortality is much higher in the fall than in the middle of winter for these small birds. Once they get fully acclimated to cold they can withstand temperatures as low as -70 F for a few hours, and -40 F for 8-12 hours (based on studies done by a colleague in Michigan many years ago).

How different these drab winter plumaged birds are from their golden summer color. Here are two Goldfinches sitting in the same part of the garden, on the stems of Purple Coneflower. (click on any of the photos to enlarge to full size)

Rumination

This is not about meditation or deep thought or reflection. It's about digestion. It's also about walking slowly and keeping your eyes open (while avoiding obstacles underfoot). I took a stroll in the backyard today, and deep in the woods my eyes suddenly wandered over to the left where I saw a pair of eyes staring back at me. I'm farily certain that this was the same doe and fawn that visited me the other morning, and here I was paying them a call during their morning rumination.

Yup, she was having a quiet laydown to digest her morning's foraging. She was quite happy to just lie there and look at me for several minutes. Her fawn bounded off up the hill and that must have made her nervous because then she got up and stood in back of a tree with just her head showing, and then finally most of her body came out from behind the tree.

As I stood there watching her watching me, she began to regurgitate and chew; it looked exactly like someone chewing gum, with the same sideways grinding motion. And then looking a little more closely at her as she was chewing I could see her swallow as a noticeable bolus of chewed wad quickly made its way down her esophagus, and just as quickly another bolus came up. The transit time couldn't have been more than 1/2 second, which surprised me because when we swallow food, it takes several seconds to get it down. The yellow line is where I saw all this activity in her neck (I colored it in to make it more obvious).

You might think this is really geeky, but I spent 4 years at the Univ of Minnesota using radiography to film turkeys swallowing their food and so comparisons with how other animals manipulate and swallow food is kind of interesting.

Ruminants (like cattle and sheep, but not horses) may take a long time to digest their food by chewing it over several times, but this makes them more efficient at digesting it, so they can get by with poorer quality forage, like what the deer will have to eat this winter when the leafy greens are all gone.

Glorious Oaks

We revere the mighty oak for its strength, its fine grain in furniture, its resilience in resisting severe weather, its tolerance of extreme heat, extreme drought, extreme cold, extremes period -- just to name a few amazing things about various oak species. This week we've also been treated to a show of glorious color put on by the red, white, black, and pin oaks in Minnesota.

Oaks on the shore of Lake Vadnais reservoir.

At Fish Lake in Maple Grove.

Early morning reflection in our local lake up the street.

Along the railroad track in Shoreview's Reservoir Woods.

This scene would have been even prettier a couple of weeks ago.

Contrary to what you might expect, these are not the leaves of red oak, but white oak!

These are red oak leaves -- but the color is highly variable. Some are redder than this.

A handy guide for identifying oak leaves:

http://www.indieprettyprojects.com/2010/04/indie-pretty-id-guide-designing-with.html

Early Morning Visitors

I have learned to keep my camera right next to the porch windows that face the backyard, for situations just like this.

There was just a small patch of early morning sun in which this doe and her fawn were basking for a few minutes.

I don't know what the doe was staring at as she looked into the ponds below her; maybe there were other deer down there. Last winter there was a herd of about 19 that moved through the open space behind our house -- a serious overpopulation problem, at least for any landscape plantings I cared about.

The doe and fawn were almost affectionate, often touching noses, even though this was a pretty big fawn to still be dependent on its mom.

This photo was taken right after I opened one of the porch windows so I didn't have to shoot through the glass (previous two pictures), and the doe immediately turned her head around to look at me. It seems like they can twist their head around to the side almost 180 degrees from front.

Then the neighbors let their dog out and she barked and ran to the back of the yard, down the hill from where the deer were standing. They went on high alert. The doe was still concerned about me, but was paying attention to the dog as well.

Both of them straightened up their head and neck as much as they could to peer into the neighbors' backyard.

The fawn soon got tired of being on high alert and stopped paying attention. Hmm... kind of like small children do.

Last Harvest of the Year

Temperatures overnight finally dipped below the tolerance zone of the remaning plants in the vegetable garden. When I looked out at the garden yesterday morning, the leaves of the pepper plants were drooping with frost damage, so I went out and harvested everything that was left. Here's what I found:

There were also some three foot tall lettuce plants that survived not only frost but lack of watering for the past month. Nothing edible there, though. I had no idea lettuce was so hearty.

You might wonder what the long stems with knobs are...those are my poor brussel sprout plants that survived the woodchuck infestation this past spring. Apparently the woodchucks ate the apical tissue that grows up to produce the brussel sprouts and these side stems had to take over, but were greatly delayed in their growth as a result of the intensive munching.

I never liked brussel sprouts until I had them steamed, fresh out of the garden, when they are tender and tasty. Sprouts from the market are tough and bitter, probably because they are full of the mustard oils that keep animals from eating them. Each little sprout is like a miniature cabbage that develops right in the notch of each leaf. I tore the leaves off of this stem to make it easier to remove the sprouts.

If you leave the sprouts on the stem long enough, they eventually will spread their leaves, enlarge their stem, and root themselves into the soil, right on the parent plant. Like these sprouts at the base of one plant did...

That fact that the sprouts resemble mini-cabbages is not coincidence -- they are both products of artificial selection for parts of the wild cabbage (really a mustard) that looks like this.

http://www.sciencephoto.com/media/39197/enlarge

Biology textbooks love to use this plant as an example of the process of natural selection (although in this case its not natural, but artificial, man-induced selection). Broccoli, cauliflower, several kinds of cabbage, kale, kohlrabi, and brussel sprouts are all cultivars of this wild mustard plant, each "stemming" from accentuation of a particular part of the wild plant.

Although mustard plants are usually full of noxious (and poisonous) compounds deterimental to insect health, the cultivars retain some useful compounds that apparently have anti-cancer properties in humans. So, eat your brussel sprouts, broccoli, and cauliflower, but steam or stir fry (don't boil) them to retain their anti-cancer properties.

Backyard biology art

Minnesotans seem to be proud of their connection to nature.  Recently, I've noticed how many displays of biological art Minnesota folk exhibit in their yards (front and back).  We have watched with great curiosity as the tree stump up the street has changed its shape over the summer.  At first we weren't sure it was biological at all, but now I think it is.



I think it might be a tree carving of a tree -- or perhaps a giant broccoli plant, which it sort of resembles from the back view. The front space is clearly designed to showcase something -- perhaps biological.



Owls are popular yard art, and are well known for their inability to scare away pesky woodpeckers that like to poke holes in wood siding.



The owl below (Olga) lived in my St. Thomas office for 21 years, where it dutifully scared away students who asked too many questions. It was carved from a black cherry stump with a chainsaw by a former colleague in the biology department.

 I have always been intrigued by this metal snail sculpture which resides on a corner across from Snail Lake Park in Shoreview. After running by it for several years, I thought it deserved to be photographed.

One of my favorite pieces of biological art is the giant frog at Tamarack Park in White Bear Lake, made from recycled materials. The long tongue protruding about 8 feet out from his head looks like the old seat of a tractor.  Various car parts, broken bottles, tires, and abandoned pillows make up his body.



Dead trees should of course be left in place to attract the woodpeckers away from your house, but there are some amazing artists that can turn dead trees into beautiful works of nature art.



Click on the image to enlarge it.
http://www.millionface.com/l/awesome-wild-life-sculpture-on-wood-pics/

I can't resist adding more of this great artwork -- probably not from Minnesota.