by Richard L. Howey, Wyoming, USA
My wife and I used to get great pleasure from planting flowers and vegetables in the spring, but as our knees and backs, muscles and joints have aged, it is an activity which, unfortunately, we now have to limit largely to hanging plants for our porches and potted plants for the patio. Raising plants at 7,200 feet in a dry plain is difficult enough, but after 5 years of drought and serious water shortages, porch and patio plants are a reasonable and necessary compromise. For horticultural optimists, spring here starts at the end of May; for realists, it begins at the end of the first week in June–although one year long ago, we had 6 inches of snow on June 7th or was it 7 inches of snow on June 6th? A quirk? An anomaly, surely. Hah! This last June 4th, we had 13 inches of wet snow with the consistency of concrete. We had 8 pickup loads of shrubbery hauled out of our yard. Try growing a garden under these whimsical climatic conditions. Pessimists don’t plant until the end of June, which means that they had better like fried green tomatoes, since the growing season here is short and we have also had snow in the first week of September. I don’t miss battling slugs and other pests in my vegetable garden, but I do miss the flavor of home-grown tomatoes, the bouquet of fresh scallions plucked from the soil, and the watery texture of leaf lettuce in an evening salad. And the celery!–Hans Magnus Enzensberger, a German poet, wrote an odd and clever little poem titled “Ode to Celery”–my lovely wife is not much fond of celery, but the celery I grew, she regarded as a delicacy–as indeed, did I, who have a more general acceptance of celery. I would never let it grow very large and, as a consequence, it was always tender and flavorful–the Chateau d’Yquem of celeries. What does this have to do with micro-gardens? Nothing, I just felt like telling you about it. Well, that’s not quite true. When one has such a short growing season, it can also mean a short collecting season so, if one wishes to maintain a variety of organisms in a quasi-natural environment, the answer is aquaria and terrariums, in other words, micro–gardens. In a moist well-planned terrarium, you can maintain a variety of mosses (be sure to include sphagnum), ferns, liverworts, and lichens. If you keep the soil mildly acidic, you can even raise insectivorous plants, such as, sundews, and Venus flytraps. Such a terrarium can provide you not only with an abundance of plant materials to study throughout the winter, but also with a variety of micro-fauna, such as, soil protozoa, nematodes, some very interesting mites and tardigrades. These moist, semi-tropical little environments can provide specimens for virtually endless hours of enjoyment at the microscope.
I like the idea of having two types of terrariums: one which is carefully planned and laid out in such a fashion as to require minimum maintenance and a second one into which you can place anything of interest you happen across and see what happens–a sort of “survival of the fittest” terrarium, which as you will doubtless have noticed is also low maintenance–I confess to being rather lazy. Remember, these are not displays to impress your horticulturally inclined neighbors; they are a means of assuring a steady supply of interesting specimens.
The situation with aquaria is similar but, for me, more complicated since, for many years, I have focused on aquatic biology. I used to keep 8 to 10 small (5 to 10 gallon) aquaria going in an area in the basement where there was sufficient light to support enough plant life so that I didn’t require air pumps, but not so much light as to produce algal overgrowths–sometimes. In other words, I had to scrape the sides of the tanks fairly regularly, if I wanted anything other than green goo. The positive side was that I could raise Daphnia, Hydra, Tubifex worms, the tube-building rotifer, Floscularia, dragonfly and damselfly nymphs, copepods, midge larvae, flatworms, gastrotrichs, and a considerable variety of protozoa and algae–not all in the same tank of course.
I even set up three 1 gallon marine tanks upstairs in an East window of my lab area. At a local pet shop (unfortunately, now defunct), I bought a couple of small pieces of “living rock” and on one of them was a small lovely, orange “sea peach” (Halocynthia) which is a plump little tunicate and tunicates are such strange and interesting beasties that I am really quite fond of them. I was especially pleased to have a living one 1,100 miles from the nearest coast. There were interesting algal forms attached to the rock, tiny “feather duster” worms that would pop in and out of their minute holes in the rock, rather like Jacks-in-the-Box. Small nereid worms were abundant and interesting protozoa as well. After a year of nice, stable, productive behavior, this “sea peach” aquarium decided to go foul and What A Stench! The next morning when I went up to my lab, my olfactory relationship to the world changed dramatically. I carefully lifted the tank and carried it downstairs, out to the side porch, down a short flight of cement steps, out behind the garage, and there dumped the whole mess onto the roots of a particularly noxious vine that I had been trying to get rid of. I set the aquarium jar aside to let it dry, so that I could later rinse it out–minus the olfactory assault. As you have probably already guessed, the vine was unfazed and apparently enjoyed its bath in saltwater.
The second tank sits back away from the window and produces mostly minute clumps of a brown algae, some protozoa and small nereid worms which, at certain times of the year, appear in large numbers.
The third tank gets full morning sun and has a rich carpet of green algae on its sides. It was this tank where, several years ago, I discovered specimens of two truly weird beasties, Trichoplax, and Gromia and since, I’ve already written articles about them, I won’t bore you with repeating myself here. Before the now-defunct pet shop closed, I would now and then obtain from them, algae scrapings when they were cleaning a tank or some bottom gravel, and all of these samples got added to my small tanks and enriched and diversified them. So, every few weeks when I would check the tanks, I could look forward to something surprising that I hadn’t seen before. For me, this is the great joy of microscopy–knowing that each day I sit down to a microscope, there is the possibility of being surprised, amazed, and astonished. There are few activities in life that offer such generous and constant rewards (and smells).
I have a number of plants in the same area. Most of them are small, but they too provide constant diversion. Some years ago, a faculty member at the university was retiring and moving to warmer climes. He had a greenhouse attached to the North side of his house containing somewhere around 50 to 60 orchid plants. I bought several quite wonderful specimens and carefully followed his instructions regarding feeding them a special fertilizer, misting them, providing proper light, humidity, and temperature. They all died but one. The survivor had a few leaves about 6 inches long. Having lost patience with orchids, I took this one and placed it in the East window of my lab area and ignored it, like my other plants, except to give them ordinary tap water twice a week. The variety of orchids is enormous and they live in some quite surprising environments. In fact, I have found two types that live here in the mountains at over 6,000 feet, one of which is a small lady slipper and the other of which is saprophytic–it has no green leaves, just a brown stalk with tiny white flowers spotted with red and can be found growing under pines in fairly dense forest.
Many orchids bloom and then go dormant for several years, but when they do bloom the flowers may last for 2 to 3 months. Well, my survivor sat sullenly in the window for 3 years and then just before Christmas, a large bud appeared. When it opened, I was delighted to discover that it was a large red, white, and green lady slipper. (Paphiopedilum sp.)
For the next 3 years, each time in December, it has produced a splendid flower. This year, however, it surprised me by producing 3! lovely blooms. I love plants and micro-beasties that thrive on benign neglect!
In addition, I have a small asparagus fern, 2 Tradescantia (Wandering Jew)–one of which has become very large and has a shamrock growing out of the middle, and a small bamboo palm plant–a strange little plant that puts out small flowering branches with tiny, bright yellow spheres that gradually open to reveal tiny flowers.
After I noticed the tiny blossoms, I immediately clipped off a few to examine under the microscope. As you can see from the above image, the reproductive parts of the flower are contained in a minute sphere created by the petals.
I also have a tall spindly False Aralia (Dizygotheca elegantissima) which puts out fans of 8 to 10 inch long, narrow, serrated leaves, 2 sundews, a small African leopard plant, a Venus flytrap, a small cluster of pitcher plants, a lavender plant and a Cobra lily. Insectivorous plants are full of amazing surprises and one can spend many months investigating their mysteries.
The cobra lily, which is sometimes also referred to as a pitcher plant, is an impressive plant. The veination is wonderful and when the morning sun comes through the window, the colors are exceptionally vibrant. This is also a plant which requires minimal care and continues to put out new shoots. Some of the “cobras” have reached a height of a foot.
Another type of pitcher plant is seen above. This one is squat and doesn’t grow to the height of the cobra lily. If you look closely at the “vase”, you can see the minute hairs pointing down that help glide the insect down and prevent its climbing back out.
The Venus Flytrap is perhaps the best-known of the insectivorous plants and one can be purchased for a few dollars. If you expect the trap to snap shut like a bear trap when an insect lands, you will be disappointed. The process is not quite so dramatic. These plants are also harder to grow successfully and, as you can see from the images, after a time the traps turn black. I have tried to follow the instructions for dealing with them when they go dormant, but I have had virtually no luck in maintaining them for any length of time.
Sundews are also readily grown and continue to put out “leaves” filled with sticky drops that capture small insects. It never occurred to me that they bloomed, so I was quite surprised to find this stalk of delicate blossoms. This is a different species than the one which Darwin wrote extensively about. If you are interested in these marvelous flora, his book on insectivorous plants is essential reading.
Sometimes when I walk past the lavender, I pluck a leaf or two and crush them between my thumb and index finger and then inhale the delicate fragrance. Each time, that experience makes me wish I had the time, equipment, means (lab assistants!), and the intelligence to explore the nature of the processes that plants use to produce odors ranging from that of lavender to the distinctive aroma of onions, the sharp jaw-clenching scent of a freshly cut lemon, the delicate bouquet of some roses, to the stench of carrion flowers. Maybe in my second to next reincarnation; the next one is reserved to study echinoderms.
If you have a lavender plant or a friend who does, take a few leaves and place one under your dissecting microscope. I think, you will be surprised and pleased at the clusters of stellate hairs covering the surface.
Tradescantia are very nice to work with and you can readily peel thin sections of the epidermis and observe the stomata.
I seem to recall reading that sundews have one of the stickiest sorts of glue known in the plant kingdom. This might be well worth investigating.
My miniature jungle is always there to provide new material to investigate, but with all my other projects, I rarely invade its realm, but it’s always there as a reserve on some snowy, dreary day.
This lovely African plant with the spotted leaves will occasionally put out stalks of interesting blooms.
This is a specimen of the so-called asparagus fern which was a common resident of many Victorian drawing rooms. It too is a very low maintenance plant and as a consequence we have a very nice relationship. I water it twice a week and it flourishes.
Violets are originally African plants and come in a great variety, many of which are now specially bred. Not only are they pleasantly colorful, but their leaves make interesting objects to study under the microscope.
Tradescantia or Wandering Jew is another common and easily grown houseplant. It is especially nice for examining thin sections of the epidermis of leaves, since after making a small incision, the top layer virtually peels off. As you can see it also puts out very nice little flowers which also are readily examined under the microscope.
This is a bloom from a Hoya. My wife is especially fond of Hoyas. This one has the popular name of Indian Rope plant. The flowers are waxy and intricate and make wonderful objects for study.
Another of my wife’s favorites is a variety of Zygocacti. She has at least a dozen types and their vibrant blooms are very cheerful.
Where does that “micro” part come in with these plants? Well, from time to time, I do scrape the soil surface and sometimes find several species of mites going on resolutely about their business. A bit of soil placed in a small culture dish with a boiled wheat grain will often yield interesting soil protozoa, including Colpoda (see Rose-Marie Arbur’s article) which has the interesting property of forming cysts and then dividing within the cyst. Cross sections of leaves, stems, roots and bits of flower parts when they are available, all make splendid objects of investigation. My False Aralia has become infested with scale insects and we are battling mealy bugs on my wife’s Ficus, but I saved those critters for another whole article, Scale Insects, Spittle Bugs and other lovelies. From my wife’s point of view, no deity in his her, or its right mind could ever have created mealy bugs.
Another virtue of maintaining such miniature and micro household gardens is that, from the microscopist’s point of view, virtually nothing need go to waste. When part of one of my orchid leaves starts to turn a deep rich brown, I can trim it off and look at sections of the part which is still green, sections from the area where it has yellowed, and sections from the brown tip areas and compare them. I have an African violet and my wife has several and when they start to sprawl, you can trim those long leaves and stems and look at sections. Several years ago, I took a number of such leaves, cut them into small pieces, put them in a medium-sized culture dish, added water and let them brew. Some weeks later when I remembered to look at them, I was delighted to find several kinds of molds growing on them, but even better some “slime molds” which, despite their name, are not really molds, but extraordinarily bizarre creatures, which sometimes behave like fungi and sometimes like giant amoebae, but which are really neither one.
In addition to the small aquaria in the window area, I have a number of small jars and dishes. They’re full of algae and some of them have large numbers of small- to medium-sized amoebae, especially Thecamoeba and Mayorella. One algal form that’s always fun to show innocent (non-microscopists) friends is Oscillatoria. You tell them to watch closely and they will observe something remarkable and then you astonish them by telling them that they are observing a plant in motion. O.K., I know that with the new classification schemes, it’s a cyanobacterium and not a plant, but a lecture on the subtleties of taxonomy is not a good way to retain friends or interest them in further exploration of the micro-word.
Today I took a look at 4 samples from my window jars. Now remember these have been ignored for many months except for adding a bit of tap water once or twice a week. I haven’t added any boiled wheat grains or rice or any other nutrients to encourage growth. Three of the samples were freshwater and here’s what I found on brief examination under 25x with my dissecting microscope:
2) minute flagellates
3) very tiny diatoms
4) Arcella (a shelled amoeba)
5) Cladocera (“water fleas”)
6) calcareous crusts associated with certain types of algae
7) clumps of green algae which I haven’t yet identified
9) small ciliates
10) a tiny peritrich (vorticellid)
11) Chlorella (a very tiny alga which some researchers have experimented with as a possible food source)
12) algal filaments
13) Hypotrichs (cirriated protozoa)
14) a small species of Paramecium
16) a midge larva
18) a nematode
19) Euglypha–a shelled amoeba
20) Chilodonella–a small ciliate with a very interest pharyngeal basket
21) a small water mite with interesting mouth parts which looked like a backward crossbow. I tried to get some pictures, but it was moving around too much and they all turned out blurred.
Not bad for benign neglect! Also, I’m sure that under the higher magnifications of a compound microscope, there are other wee beasties which I didn’t notice. So, one could spend weeks just trying to identify the small flagellates, ciliates, diatoms, and algae.
The fourth sample was from one of my marine aquaria. It too just sits there neglected–no pumps, no filters, no food. A bit of freshwater from time to time to compensate for evaporation so that the salinity doesn’t get too high. Here there was less variety, but lots of filamentous algae, tiny flagellates, copepods, and what was perhaps a Gromia or it could have been an egg of some unknown critter. There are also small nereid worms. But, at the bottom of the Petri dish were enormous numbers of very small diatoms and foraminifera shells. Once again, one could spend weeks just trying to identify the members of these last two groups.
When I really want to get things stirred up and find out what’s lying dormant or encysted, then I add a few rice grains or boiled wheat grains. Almost always, after a week or two, organisms start appearing that weren’t observed before. These micro aquatic and terrestrial gardens can provide a rich source of material for long winters when one can’t get out to collect.
All comments to the author Richard Howey are welcomed.
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