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The Angiosperms are the true flowering plants. The name means "covered seed" which means that the ovule (the egg cell) is covered by an organ called the ovary. As the egg develops to a seed, the ovary often develops as well--into the fruiting structure. The flowering plants are more recent evolutionarily than the gymnosperms and more diverse and variable.

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Aphids are tiny insects that feed on nutrients from plant stems, buds, and leaves. They come in many varieties, and are known to rapidly multiply and consume plants with weak immunite systems.

Aphids have a proboscis which contains four sharp stylets which is used to pierce plant tissue and suck out the nutritive juices. Horn-shaped tubes at the rear end of the aphid are called cornicles, and they secrete a waxy substance. Aphids also secrete a sweet substance called honeydew. Ants are naturally attracted to this honeydew and are often found around sites infested with aphids.

Aphids are eaten by ladybugs and other carnivorous insects. They are also naturally repelled by the following plants planted nearby: Catnip, Chives, Coriander, Dried & Crushed Chrysanthemum, Eucalyptus, Fennel, Feverfew (attracts aphids away from Roses), Garlic, Larkspur, Marigold, Mint, Mustard, Nasturtium, Onion, Oregano, Petunia, Sunflower.

In 1975, Benoît B. Mandelbrot, a French American mathematician, coined the term fractal to describe mathematical structures that represented forms found in nature, and published his ideas in "Les objets fractals, forme, hasard et dimension".

While on secondment as Visiting Professor of Mathematics at Harvard University in 1979, Mandelbrot began to study fractals called Julia sets that were invariant under certain transformations of the complex plane. Building on previous work by Gaston Julia and Pierre Fatou, Mandelbrot used a computer to plot images of the Julia sets of the formula z2 − μ. While investigating how the topology of these Julia sets depended on the complex parameter μ he studied the Mandelbrot set fractal that is now named after him.

Now, the Mandelbrot Set is more formally defined as: z2 + c. In comparison, Mandelbrot's early plots using parameter μ are left–right mirror images of the now, well-known computerised image of the Mandelbrot Set (now in 3D!).

In 1982, Mandelbrot expanded and updated his ideas in his book "The Fractal Geometry of Nature".
Before Mandelbrot, fractals had been regarded as isolated curiosities with unnatural and non-intuitive properties. Mandelbrot brought these objects together for the first time and turned them into essential tools for the long-stalled effort to extend the scope of science to non-smooth objects in the real world. He highlighted their common properties, such as self-similarity (linear, non-linear, or statistical), scale invariance, and a (usually) non-integer Hausdorff dimension.

He also emphasized the use of fractals as realistic and useful models of many "rough" phenomena in the real world. Natural fractals include the shapes of mountains, coastlines and river basins; the structures of plants, blood vessels and lungs; the clustering of galaxies; and Brownian motion. Fractals are found in human pursuits, such as music, painting, architecture, and stock market prices. Mandelbrot believed that fractals, far from being unnatural, were in many ways more intuitive and natural than the artificially smooth objects of traditional Euclidean geometry.


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Bruce Charles 'Bill' Mollison (born 1928 in Tasmania, Australia) is a researcher, author, scientist, teacher and naturalist. He is considered to be the 'father of Permaculture', an integrated system of design, co-developed with David Holmgren.

Bill professed that combining our resources in an intelligent manner will lead to positive developments in agriculture, horticulture, architecture and ecology and also improve our way of life, economic and legal systems, business practices and strengthen communities worldwide.


Bulbs are rosette stems surrounded by fleshy leaves that store nutrients. A bulb consists of a stem from which modified fleshy leaves develop. The fleshy leaves are circular and hollow; new leaves develop within the older leaves. Leaves are attached to the 'stem' at nodes and spaces between nodes are called internodes. The presence of nodes and internodes means that the bulb is actually a modified stem. The papery covering is called a tunica.

Tunicate bulbs produce a new (adventitious, not pre-formed) root system annually from the basal plate. Roots appear soon after planting the bulb.


Cacti are common in most desert systems. These hardy plants can go weeks without water.

Cactus thorns are modified stems that protect the plant from grazing animals. Spines of a cactus are modified leaves.


The corm is a relatively solid modified stem that has a few fleshy leaves. The node is the point where the leaf attaches to the stem. The presence of nodes and internodes makes the corm a modified stem. The papery tunic on the outside of a crocus corm is the dead petiole from last year's leaf. Corms also have a nonpersistent root system that lives only one season. In addition to normal fibrous roots, corms and some nontunicate bulbs have special roots (contractile roots). Because new corms develop on top of old, they are closer to the soil surface. Corms too close to the surface could suffer winter injury. Contractile roots are capable of becoming deeply anchored and contracting to pull the corm deeper into the soil. Thus corms can change their depth in the soil.

Examples: Crocus, Gladiolas

A decidious plant sheds foliage seasonally or at a certain stage of development in its life cycle.

In botany and horticulture, deciduous plants, including trees, shrubs and herbaceous perennials, are those that lose all of their leaves for part of the year. This process is called abscission.
In some cases leaf loss coincides with winter - namely in temperate or polar climates. While in other areas of the world, including tropical, sub-tropical and arid regions of the world, plants lose their leaves during the dry season or during other seasons depending on variations in rainfall.


  • [Trees] Acacia, Aspen, Beech, Bilberry, Birch, Cherry, Elm, Maple
  • [Shrubs] Honeysuckle, Viburnum
  • [Vines] Grapes, Poison ivy, Virginia creeper, Wisteria

Compare to Evergreen

An epiphyte (or air plants) is a plant that grows upon another plant (such as a tree) non-parasitically or sometimes upon some other object (such as a building or a telegraph wire), derives its moisture and nutrients from the air and rain and sometimes from debris accumulating around it, and is found in the temperate zone (as many mosses, liverworts, lichens and algae) and in the tropics (as many ferns, cacti, orchids, and bromeliads).
A plant that retains green foliage throughout the year.


Compare to Decidious

Groundcover plants are found on the 5th layer of the forest ecology. Groundcover plants are particularly useful in protecting soils from water loss and erosion, decompacting hard ground, and filling a niche that could have otherwise overgrown with weeds.

Some examples are: English Ivy, Japanese Spurge, Ghost Fern, Juniper, Woolly Yarrow, Sandcherry, Bergenia, European Ginger and Bishop's Goutweed.
The Gymnosperms are the cone-bearing plants--pines, junipers, spruces, firs, hemlocks, bald cypresses, eastern white cedar, Atlantic white cedar, and their relatives. The name means "naked seeded" which means that the ovule (the egg cell) is not covered by an organ (the ovary in floweirng plants) but is born on the scale of a structure called a "cone". When the cone and seeds mature, the seeds are often exposed to the environment (however, the cone scales can be fleshy and can tightly cover the seeds, as in the junipers).
Nitrogen fixation is the natural process, either biological or abiotic, by which nitrogen (N2) in the atmosphere is converted into ammonia (NH3). Biological nitrogen fixation was discovered by the Dutch microbiologist Martinus Beijerinck.

Microorganisms (Diazotrophs) that fix nitrogen

  • Cyanobacteria
  • Azotobacteraceae
  • Rhizobia
  • Frankia

Rhizobia are Gram-negative soil bacteria with the ability to establish a N2-fixing symbiosis on legume roots and on the stems of some aquatic legumes. During this interaction bacteroids, as rhizobia are called in the symbiotic state, are contained in intracellular compartments within a specialized organ, the nodule, where they fix N2. Rhizobia within nodules in their root systems, produce nitrogen compounds that help the plant to grow and compete with other plants. When the plant dies, the fixed nitrogen is released, making it available to other plants and this helps to fertilize the soil. Similarly, Frankia, Gram-positive soil bacteria induce the formation of nitrogen-fixing nodules in actinorhizal plants.


Rhizomes are underground stems that grow near the soil surface. They typically have short internodes and scale leaves, and produce roots along their lower surface. They store food for renewing growth of the shoot after periods of stress.

Example: Prayer Plant, Queensland Arrowroot, Clivia miniata, Rhoeo (Moses in the Cradle), Kangaroo Paw, Iris, Ginger, Canna Lili


Stolons or runners-are horizontally oriented stems that grow along the soil surface. Their function is vegetative production.

Strawberries are normally propagated asexually by two different methods: runners (stolons) and crown division.