From My Nature Journal: Running with the Bison

Well, ok, they weren’t really bison, just tumbleweeds…

Remember those old movies where a horseman would be galloping alongside a herd of wide-eyed bison as they stampeded across the plains, dust flying amidst thundering hooves? I had my closest experience ever to that interesting feeling today…

On our way to Chicago to visit family for the Thanksgiving holiday, we happened to leave the day following an early and burly winter storm yesterday, a fierce and old-fashioned nor’easter; its blizzard conditions packed some ferocious winds in excess of fifty miles per hour. But the snow had given way by today to a crystal blue Colorado sky, and the roads were clear and dry. We’ve driven that angled stretch of Interstate 76 between Denver and the Nebraska state line many times, always marveling at the piles of tumbleweeds stacked up against the barbwire fences on the east side of the highway. In fact, on the days we’d made a predawn departure, they had often provided quite the curious scene as a colorful morning sky dawned beyond them.

But here’s the thing: yesterday’s storm had moved all the tumbleweeds to the west side of the highway, and, as so typically happens, yesterday’s gale force winds from the east were matched almost completely today by their corresponding counterforce from the west -- all that unstable air had to somehow get back to the place it had occupied the day before! So as we traveled east and northeast along the interstate, hundreds and hundreds, nay, thousands of tumbleweeds had to do the same, all of them being blown back to the east side of the road. The first time we came upon a bunch of them moving east or northeast with our car, I commented to Gail that I felt like we were in one of those old movie scenes surrounded by a stampede! We, of course, traveled ‘with’ the ‘herd,’ inevitably running over many as they exploded in the wind around our car. But what a sight the vehicles were on the opposite side – many of them, cars and trucks alike, completely covered across their grills with growing tumbleweed layers. It made them look like a bunch of thickly bearded goblins running down the road.

Tumbleweeds have always fascinated me. (Apparently they’ve also fascinated my sister Denise – she once asked if we’d bring her one in Chicago, a request we were glad to oblige. But it sure took up a lot of room in the back seat and we still find an occasional poker sticking out of the cloth. Also, I’m not sure what my beloved brother-in-law had to say about it…) As we hike, we see them as small as basketballs and as large as Volkswagen Beetles. The pair shown below to the left were a couple of random ones we saw as we walked along a Las Cruces, New Mexico trail beside the Rio Grande.

In spite of their ubiquity in cheesy western films (picture one now rolling lazily across the dusty ghost-town street), the most common species in the interior west today is actually not even native but invasive. It’s called Russian Thistle, and is reputed to have come over in a shipment of flax seed from Eastern Europe to North Dakota in the 1870’s. Who knew? But there are lots of different kinds, and they vary widely in size and structure. Wikipedia says, “A tumbleweed is a structural part of the above-ground anatomy of a number of species of plants, a diaspore that, once it is mature and dry, detaches from its roots or stem, and tumbles away in the wind... Tumbleweed species occur most commonly in steppe and arid ecologies, where frequent wind and the open environment permit rolling without prohibitive obstruction.”

Beyond their physical fascination, I haven’t taken them particularly seriously over the years except when I try to aim my car at them as they cross a highway. You get points for that, you know, even if it makes your wife nervous. But farmers and agronomists have learned through hard experience to treat them much more seriously. Not only do they crowd out native foliage, but in drier regions they also starve both native plants and dryland crops of much needed moisture, each tumbleweed plant using up to forty gallons or more of water during a growing season. They also can negatively impact soil erosion, and produce fire hazards as they stack up in massive piles against buildings or vehicles. By and large, they are bad dudes.

But back to the ‘diaspore’ thing from the Wikipedia article. Though it’s just one word in the explanatory paragraph, this is the part that has always fascinated me most. Tumbleweeds are made to roll, not to provide forlorn and lonely ambience for old westerns, but in order to disburse their seed. Plants have different methods for seed dispersal – they can explode them, fly them, hitchhike them on animals or humans, or just drop them – but I think tumbleweeds are the only ones where the whole plant becomes the mechanism to deliver its seed wherever the wind rolls it. As it rolls and breaks down, seeds fall, or small pieces of the plant break off with seed attached, finding potential welcome in a harmonious place. They leave a mark of their presence wheresoe’er they roam.

I want to leave seeds of life,

hope and faith wherever I go.

How about you?

Noxiousness aside, of course, I guess in a different way I want to be like that, too. I want to leave seeds of life, hope and faith wherever I go. How about you?

Now thanks be to God, who always leads us in triumph in Christ, and reveals through us the sweet aroma of his knowledge in every place… a sweet aroma from life to life.  

(2 Corinthians 2:14-16)

~~ RGM, from a 2014 entry in my nature journal,

adapted for my blog on November 25, 2016

From My Nature Journal: All From a Knock in the Head…

“Yowwww!?!!!”

I was walking in the Michigan woods last fall and, out of the blue (literally), something hit me in the head, hard! Looking to where I had heard whatever it was hit the ground and had seen in my peripheral vision something roll to a stop, I found a large, fresh acorn. Maybe a squirrel had just clipped it and let it drop (or aimed it -- I have had that happen to me before with pinecones!). But the oak above was large enough to impede my ability to spot any guilty party nearby. The knock really smarted, though, and I rubbed my head while wondering if it drew blood. The tip had a sharp point, and the nut may have hit me from that position.

Thinking of Isaac Newton under the proverbial apple tree, and the alleged falling orb by which he brilliantly began to deduce the force of gravity, I wondered if there was anything brilliant I was supposed to construe from this occurrence -- besides perhaps wearing a hat when I walk under oak trees in the fall, or avoiding proximity to coconut trees altogether. So it set me to thinking. Why, indeed, do some trees produce large seeds like this, and others produce tiny, wispy ones that float on the breeze? And what is their essential difference? I decided to do a little research, and here is what I found.

In general, trees produce one of two kinds of seed: one has enough substance to give the potential plant some resources with which it can get its start in life, so to speak, and the other kind does not. Rather, the latter’s seed is released to find its own resources if it can. Interestingly, the tree that produces the first kind expends so much energy preparing a seed with its own resources that it doesn’t produce many seeds; conversely, the tree that produces the second kind, expending so much less energy preparing its seed, can release them by the millions. As Bernd Heinrich says in his book The Trees in My Forest, “A tree has only so much to give… It can either have millions of seeds, each with a tiny inheritance… or relatively few seeds, each endowed with a large inheritance.”

Cases in point: my assaulting oak compared with the ubiquitous aspen. The oak produces a limited number of acorns, dropping them in the fall with, of course, the assistance of squirrels. All nut trees, oaks included (and coconuts!), are of the first kind mentioned above: the entire seed contains enough resources to get it started even on a less-than-perfect patch of ground, even in the shade. By contrast, an aspen releases millions of cottony tufts to the wind, each carrying a seed so small it can hardly be seen. One can brush against my face when it flies in May and I likely may not even feel it, yet the ground might be covered in the down. Each aspen tuft and seed drifts randomly in the rare hope of landing on some hospitable piece of real estate, the one with the most suitable depth and health of soil, the most advantageous amount of sunshine and most suitable quantity of moisture to thrive. Infinitesimally few are so lucky, for, on

Aspen seeds

average, perhaps only one of the seeds a mature aspen releases in its lifetime will grow to fully replace it. (Think averages. If this were not true, northern climes would be covered with nothing but aspens.) Luckily, aspens have another thing going for them by which they are far more successful in their reproductive efforts: most aspens grow from shoots sent underground by a parent plant, and are thus clones of the original. It’s what allows aspens to be the first up after a blowdown, fire or clearcut, without having to wait for a parent tree to release its seed.

But I also found some other interesting things. For example, I wondered how oaks reproduce successfully if animals eat all their acorns. After all, they are a favorite of bear, deer, jays, squirrels and others. I knew, of course, that one of the ways is that squirrels forget (or don’t quite get back to) all the places they’ve buried their stores, and those left behind often sprout, with gratitude for the convenient planting. But in addition to this, I found that nut bearing trees don’t produce every year, and after producing very well can go for several seasons with no crop; this gives them a better chance of eventually sneaking in some seeds that don’t get eaten, while the animal, who has been used to feasting there each season, turns up empty a year or two and writes the tree off his to-do list. I thought that was pretty wonderful.

Of course, thinking about these things leads me naturally to think of Jesus’ parables of the good soil (Luke 8:4-18) or the mustard seed (Matthew 13:31-32). Each of these texts would offer me much to consider if I spun them awhile through my cranium. But the concept most clear and dear to me from this musing is a takeoff on his little parable of the dying kernel in John 12:24, “…Unless a grain of wheat falls into the earth and dies, it remains by itself alone. But if it dies, it bears much fruit…” We humans die as a seed, but of the first kind, like the acorn – with all the resources having been made available while we lived that would be necessary for us to sprout and live fruitfully again, even forever. The only difference is that we need to have realized and taken advantage of it.

Hmmm, all from a knock on the head…

~~RGM, May 12, 2016