Apples are red, blueberries are blue...

but neither was really intended to be good for you.

Warning: this is a geeky science post brought on by wondering about where color in leaves came from.

The wonderful thing about traveling is the amazing variety of fruits and vegetables that you see for sale on any given market day. Like this one in Guatemala:

And this one in Cambodia:

I got to thinking about the levels of anthocyanins, carotenes, etc. in colorful fruits and their anti-oxidant properties and wondered if there was any research that supports the contention that we should eat lots of green and red (or orange) vegetables for their anti-oxidant content. Should we all be putting lots of these on our cereal in the morning to boost our free-radical fighting capabilities?

Before I get too far in this discussion you must realize that the price of breathing oxygen in order to generate all the wonderful chemical energy that sustains our daily activities is that oxygen is highly destructive and leaves lots of loose ends (like hydrogen peroxide) that can do permanent damage (free radicals). That's why anti-oxidants are important, to scavenge the free radicals and eradicate them from your body. So what's the answer?

A big summary written by the European Food Safety Authority (and a few other published articles as well) indicates that there is no good evidence that increased consumption of anti-oxidants in the diet produces an increased anti-oxidant capacity in humans. The ingested anti-oxidants are likely thoroughly digested and any protective effects noted with their consumption is probably due to secondary reactions associated with the vitamins, minerals, or fiber in the food. But they taste good fresh out of the garden, so pile them on.

Here's my second day harvest of raspberries earlier this summer. Yum!

You know it's fall when...

The sun no longer wakes you at 5:30 a.m.

3 p.m. in the afternoon feels like it's about time to make dinner.

Most of the summer bloomers have died back and asters take over the garden.

The milkweed pods have exploded their seed, and the last clutch of milkweed bugs hurry to mature so they can fly away.

You see scenes like this on your walks through the "backyard".

Did you ever wonder what gives the leaves of some trees such spectalular color in the fall? Yes, it's those other pigments (i.e., light harvesting complexes) in the leaves that are unmasked once the chlorophyll has been ripped apart and its nitrogen transported back to the roots for winter storage. The yellow (xanthophylls) and the orange (carotenes) pigments and combinations of those two make the birch and aspen leaves yellow, some maples orange, and oaks orangy-brown.

But what makes sugar maples so red? It's not a pigment. It's the production of an anti-oxidant compound called anthocyanin, formed by excess sugar attached to a protein. The sugars are formed during photosynthesis on warm days, but fail to be transported out of the leaves during cool nights. So, fall temperatures and reduced daylength contribute directly to the glorious colors produced.



By the way, anthocyanins are also produced in ripening fruit, to signal that its ready to eat. Depending on pH and concentration of anthocynanins in the skin or flesh of the fruit, the resultant color may be deep red, blue, purple, or even black.

In the high Sierra backyard

I haven't been keeping count, but this might be about the 20th trip to the back country of the high Sierras.  We started hiking portions of the Pacific Crest Trail in northern California in 1988 and have rarely missed a year since then.  We come for the grandeur of the scenery and lately to prove to ourselves that we are still not to old to do this.  But this year, the 38 miles in 5 days was rugged with lots of up hill and down.  12 miles of hiking on day 4 gave me very sore feet.  The pack is always too heavy, and the hills seem to get steeper each year, but the views are definitely worth it.  A few of my favorite scenes of mountain-, meadow-, and water scapes.

Tuolomne River with Cathedral peaks in the background

Waterfall on the Tuolomne River



Our campsite on what we thought was Miller Lake (but wasn't).

With threats of storms to come in this early fall weather, the cloud formations produced some dramatic photos.

Life is challenging at 9000 feet in the high Sierra, but plants and animals somehow manage to tough it out.  I was struck by the ability of these pines to gain a foothold in small cracks in the granite slabs and survive not only burial in the deep winter snow, flooding in the melting spring run-off, but then drought during the dry summers.



We saw more mule deer on this trip than I have ever seen before on a hike.  It could have been because they were moving down from higher altitudes, or it could have been that there were fewer hikers around scaring them off (we saw no humans for more than 48 hours!).  The meadows were drying out, but the does still had what appeared to be young fawns, probably sapping their energy with their demands for milk.  You can see the ribs on the doe, and the fawn didn't appear all that healthy, defecating twice within a few minutes but not eating anything.  It reminded me of a calf with "scours".



Every canyon lures us onward, but sometimes you're just too tired to go on.  Next time.

Garden Thief

Woodchucks did a number on the garden earlier this spring. I thought it was just one very large one eating out there, but then we began to see smaller ones moving around in the dense crop of coneflowers and cup plants just starting to grow. The wildflower garden is meant to survive on its own, without help from me (except for getting rid of noxious weeds), so I let the woodchucks alone. Within a week, however, the Golden Alexander (first blooming spring flower in the garden) was chewed down to its roots, Cup Plant was similarly mowed down, and the Spiderwort was on the verge of disappearing altogether. OK, enough of that. I decided I had to trap and remove the pests, especially "big mama".

After setting the largest live trap we had up in the middle of the garden and baited with what we thought were woodchuck delights (cabbage, carrots, apple and oatmeal), we caught a racoon instead of a woodchuck. Setting the trap in what we thought was their runway into the garden didn't help either. Then I noticed that the runway actually extended right to the edge of the yard, and there was a clear path down the hill into the neighbor's yard, leading right up to a big dirt mound with a large hole in one side of it. Aha -- this must be the nest.

What a surprise when I went to set up the trap right at the burrow and found 5 baby woodchucks sunning on top of the dirt mound. So, if I was going to protect the wildflower garden, I would have to remove 6 woodchucks, and so far I hadn't been able to trap even one.



Here are 4 of the 5 babies basking on top of their burrow. I had to peer through the leaves to photograph them because they were rather shy. Finally, after many attempts I managed to catch the mom and then 4 of her 5 babies. The last one was very savvy and eluded me for almost two weeks, but I finally got him. I drove them about 5 miles away to a big county park and let them go there. Maybe they managed to find each other. Good riddance.





Did you know that woodchucks (aka groundhogs) are actually the largest member of the squirrel family in the upper midwest? The MN DNR website recommends spraying a solution of 2/3 water to 1/3 ammonia solution on plants you care about in your garden. If it tastes bad enough, woodchucks will leave it alone. I'll try that next year.

Woodchucks are among the largest hibernators (contrary to popular belief, bears do not hibernate), with adults spending probably only 5-6 months above ground in MN feeding, raising babies, and fattening up for the next long "sleep" cycle. Hibernation isn't really sleep, in the same sense that we sleep. It's more of a deep coma, with markedly reduced breathing, heart rate, and absence of reflexes. Puxatawny Phil might emerge in February to check out the remaning length of winter, but I bet MN woodchucks stay put until the ground thaws in April. .

Ode to the prairie

My husband loves prairies; he is an expert prairie biologist. So maybe this is an ode to him.

Last weekend we visited three prairies in northern and west-central Minnesota so Alison could capture the "essence of prairie" in digital form. See her Aug 30 post below for some dramatic examples. I thought I should add that we also saw some animals (besides cows) and some quite unexpected plants while walking around on some of the preserves. For example, do you know what this plant is? Not your typical prairie plant, but useful in many ways -- some illegal.

Sunset on the prairie makes it light up with color. As we were out driving the backroads at sunset we saw this male marsh hawk land in the grass. Alison and I hopped out of the car and tried to sneak up on him to get his picture, but alas he flew quickly away.

Dragonflies were especially abundant, and we managed to get close up to some different species than we see around the Twin Cities. This one was really huge (a whopping 3-4 inches) and extremely lethargic, and let me get right up in his "face".

like this.... I think this is a juvenile (just emerged) Common Green Darner, based on its gray- brown eyes with the yellowish rim, green thorax, brown abdomen, and bi-colored legs. The abdomen has a bright blue lateral stripe in adult males.

Another curious feature is the bulls-eye that appears in front of their eyes. I found a newly emerged Green Darner in my backyard the other day and got a better picture of the bulls-eye. I wonder what its purpose is.

Darners are one of the most common big dragonflies we see buzzing over the fields above our heads. Alison's prairie pictures (below) were full of dragonfly silhouettes. However, they never seem to tire cruising and darting and are hard to find at rest.

Here's another cooperative subject, a Band-winged Meadowhawk, sunbathing on the gravel near sunset. This is also a juvenile, based on its brown abdomen with black stripe. The adults have a red abdomen. The striking amber wing pattern is unmistakable for this species though. Like other meadowhawks, it hunts in low vegetation, bogs, and slow moving water. It is more common in the western US where it has less competition from other small dragonflies.

There were other meadowhawk species flitting through the low prairie vegetation as well. Alison found some individuals that are either Cherry-faced or Ruby Meadowhawks; apparently you can only tell these apart by looking at them under with 20X magnification.





The prairie is not just a flat pancake in northern and central Minnesota. Glaciers left numerous gravel (and boulder) deposits as they pushed south, while scooping out deep gouges that turned into pothole lakes. Drier hilltops and wetter creek bottoms add to the diversity of life that lives there. I had to watch where I was walking through part of the wetter prairie as we scared up frogs and toads. Sometimes they just hunker down and assume you won't step on them. This guy did not want to budge, even when I got my camera lens down 6 inches from his face.

The prairie is an interesting place to explore, and is certainly more diverse than you think when you drive by what looks like monotonous tall grass.