Eco-Farm: An Acres U.S.A. Primer — Lesson 2: The Forgiveness of Nature, Part 2
This is an excerpt from Charles Walters’ Eco-Farm — An Acres U.S.A. Primer, available from the Acres U.S.A. bookstore at bookstore.acresusa.com. Read more excerpts from this book using the category “Eco-Farm” (https://members.acresusa.com/magazine-features/eco-farm/).
5. Monocots and dicots
As the name implies, monocots have seeds which contain only one seed leaf. Dicots have seeds containing two seed leaves. All are flowering plants, and all rely on sexual reproduction, probably nature’s greatest invention, rivaling only death as an evolutionary mandate.
Among the important monocots and dicots in world agriculture are the following:
Monocots:
- Bananas
- Corn
- Canes
- Grasses
- Lilies
- Orchids
- Onions
- Pandanus
- Palms
- Sedges
- Taros
- Vanilla
Dicots:
- Beans
- Rubber
- Cocoa
- Coffee
- Oranges
- Breadfruit
- Yams
- Croton
- Crotalaria
- Most garden flowers and vegetables
6. The seedbed becomes a rootbed
Seedbed is one of those words we wish had never been invented. At first glance, it seems appropriate enough—a prepared bed for placement of seeds for optimum growth and production. But nothing is static in any form of agriculture. The seed doesn’t stay a seed. Very soon the seedbed becomes a rootbed, and what may be suitable for a seed eating up its sustenance simply won’t do when tap roots go down and lateral roots venture out hard on the hunt for nutrients.
When a seed germinates, a tiny root peeps out. It is called a radicle. As it ventures deeper and deeper, it often becomes a taproot, thus changing its role from being an opener to being an anchor. At the opening to the seed made by the radicle, two more roots venture forth. Styled lateral roots, these adventitious roots have roles that differ according to whether a plant is a dicot or a monocot The taproot is front burner stuff when the plant is a dicot. Not so with the monocot which relies more on the adventitious roots for stability against stress.
Much like an army patrol, the root tip pushes ahead, down into the soil, as if paving the way for a whole host of fine white hair troops looking for a meal. Fine root hairs not only seek and find a whole cafeteria of food, they also carry home the water needed for plant life.
Watching a corn plant grow takes on the color of a miracle in slow motion. Little swellings appear along the sides of larger roots, and these form root eyes. Here lateral roots will form. If the stress of life breaks away a root, a new root will appear as if by magic out of one of the root eyes. After the soil really wakes up in spring, one can sometimes hear corn growing, so rapid and fantastic is the scenario of a seed sprung to life.
An old paradox applies to almost any discussion of plant life. It says, all generalizations are false, including this one. One must always keep this point in mind when summarizing. Roots nevertheless have several things in common. They anchor the plant in the ground. They take up plant nutrients and participate in water transpiration. They store and hold plant food. And—here goes the generalization out the window—they propagate some species of plants, the sweet potato, for instance.
The sweet potato is really a swollen root plant. The familiar Irish potato is a tuber that got mixed up in the evolutionary process and now grows its fruit on an underground stem.
There are plants, of course, that have no root hairs, and there are plants that can be propagated with cuttings, such as grapes, in which case nutrients enter through the thin root epidermis.
7. A typical plant
From the ground up, here is a typical plant—corn.
The soybean plant has a different nomenclature.
Here are wheat, left, and rice, right.
8. Seeds and stems and leaves
Seeds and stems and leaves have their several functions, stems carrying water and nutrients, holding up the structure of the plant and the fruit it produces. Seeds warehouse life and preside over the genetic makeup, the stamina, the health and the production capacity of the commercial plant.
It is the leaf, however, that now attracts more attention than it has heretofore. Not that the nature of the plant has changed. Those foliage leaves at the tips of stems and branches still handle the chlorophyll payload that permits plants—during daylight hours—to make carbohydrates from starch and sugar from oxygen, hydrogen and carbon. A leaf has its own nomenclature. The skin is called a cuticle. It has tiny holes called a stomata. The stomata allows a leaf to breathe.
The leaf blade is held out, stretched and shaped by a midrib, a sturdy fiber that takes on the function of a barn’s roof timber. Leaf veins run across the leaf like secondary roads at the end of each section in the countryside. Sometimes they make a network, like trails and traces lacing country roads together in Vermont, and sometimes they keep their straight lines, like an Iowa section line. Dicot leaves form up at the stem via a narrow leaf stalk—the petiole. Monocot leaves attach themselves to the stem with a sheath or leaf base.
Here is a dicot leaf, in this case the willow.
The arrowhead leaf is typical of the monocot plant.
It is probably an oversimplification, but leaves come in two shapes— simple and compound. A leaf system is compound if it is composed of two or more small leaves.
