Wednesday 30 May 2012


Plant leaves come in a variety of shapes and sizes, from the tiny leaves of mustard seeds to the large leaves of banana plants.

Leaves enable the plant to covert sunlight into energy through photosynthesis.  The surface area of the leaf is very important when it comes to their ability to absorb sunlight, which is mainly absorbed by a thin layer of cells just below the surface of the leaf.

In shady areas having a larger leaf can give a plant an advantage over its smaller leaved neighbours, as bigger leaves can absorb more light. In the lower layers of the rainforest there is little light because of the shadow caused by the canopy. This means the leaves need to be bigger to absorb more light to help them survive.

Surface area affects water loss, so large leaves will loose water more quickly through their stomata cells located on the underside of the leaf. Depending on the location, leaves in a shady place will often loose less water than those in sunlight; due to possibly lower temperatures, less wind and that shaded leaves will also likely be more sheltered. This means shaded leaves can often get away with being bigger too.

To grow big leaves, a tree needs plenty of nutrients. Wet soil encourages 
decomposition of plant and animal matter in the soil, which in turn means that the soil of rainy places often contains a lot of nutrients. This rich soil allows the trees that grow in it to more easily produce big leaves. The soil in a dry location would have slower decomposition, so nutrients may be harder to come by.

Moisture and heat can affect the size of plant leaves. Some plants can reduce water loss through the stomata by fixing carbon at night. Cacti have modified their leaves to become thin spines which do not lose water through transpiration.  

Leaves also collect rainfall and direct it to the tree's root system. The environment of a rainy location encourages the trees there to grow big leaves

The amazon waterlily (Victoria amazonica) has giant leaves that grow up to 3 metres in diameter.  They spread across the water like rafts and can support a child weighing 30 kg / 200 pounds on a single leaf.

Raphia farinifera
However, the largest leaves belong to the raffia palm, Raphia farinifera, which grows in the tropics of South America and the Indian Ocean islands. Whilst the average leaf size ranges from 4 - 20 feet long, a single leaf of the raffia palm can reach more than 70 feet long and 19 feet wide! This is as high as a seven story building.   Fibres are extracted from the long leaves and stalks and used for ropes, sticks, supporting beams and various roof coverings.

For related articles click onto:
The worlds largest vegetable
What is a vegetable?
What is the difference between a vegetable and a fruit?
Which plant has the largest seed?
Which plant has the largest leaves?
Which plant has the largest flower?

Sunday 27 May 2012


A seed contains the young plant embryo within a protective seed coat.  Within it is all the necessary material to produce a new plant, given the right environmental conditions.  Most plants reproduce through the dispersal of their seeds. 

There is an enormous diversity in the sizes of seeds of plants.  Seeds come in all shapes and sizes, from the tiny seeds of orchids to the golf ball sized seeds of the avocado. Even within a single genus of plants, seeds may vary greatly in size.  

Variations in seed sizes occur as plants adapt to different dispersal methods.  Seeds that are dispersed by wind such as dandelions and sycamore are small and light. Burdocks and cleavers have tiny hooks on their seed coats which catch on passing animals and hitch a lift.  Some seeds, including many fruits, are enclosed in a tasty flesh which is attractive to animals and subsequently dispersed by them through there droppings or burial. Plants such as peas or laburnum burst open and disperse their seeds in all directions.  Poppies are shaken by the plant to disperse tiny seeds.  Other seeds such as coconuts are waterproof and can float.  

Some plants produce many small seeds to increase the chances of new plants germinating and surviving. Others produce a large, single seed.  Larger seeds have a competitive advantage over smaller seeds as they have material available to them that makes up for the lack of resources in the environment.  They are capable of faster growth and can grow in poor soils.  They can survive burial by litter and their thicker seed coat enables them to avoid desiccation during dry spells and insulate during cold spells.

The largest seed in the world can take ten years to develop and can grow up to 45 cm long and weigh up to 40 pounds. This is the seed of the Seychelles coconut.  The fruit of this palm looks like two coconuts joined together and so is also known as 'double coconut'.

These coconuts grow on palm trees found only in the Seychelles Islands near Africa.  Growing near the seas, these coconut seeds often fall into the ocean and float away to be washed up on distant shores.

Thursday 24 May 2012


Gold, Frankincense and Myrrh were gifts borne by the three wise men to celebrate the birth of Jesus. Although we are familiar with the biblical story of the gifts presented on this Christmas day, we can be uncertain about what exactly some of these items are.

Myrrh is a natural gum resin derived from tree sap and prised for its distinctive fragrance. It is a natural blend of essential oils and resin that is used in ointments and perfumes.

The resin comes from  species of the Commiphora tree, found in north east Africa and adjacent areas. Myrhh is commonly harvested from the species Commiphora myrrha and Commiphora momol.

To extract the sap from the Commiphora tree a longitudinal cut is made in the trees trunk, which pierces gum resin reservoirs located in the bark. A yellow waxy gum oozes from the cut and hardens to form tear shaped droplets which harden on the side of the tree.  The gum becomes hard and glossy after harvesting, and darkens with age to become reddish in colour.

For related articles click onto:
What is Christmas?
What is mistletoe?
Why do we kiss under the mistletoe?
What is Myrhh?
What is frankincense?

Tuesday 22 May 2012


The sea sponge is classified as an animal, albeit simple in make up.  This is because there are some key characteristics that defines the sea sponge as an animal, rather than a plant.

Their scientific name is Porifera, meaning animals that have pores. There are more than 15,000 varieties, and they live primarily in the ocean, some near the edge, some in deep water, some in fresh water.

The main reasons for classification of sea sponges as animals is outlined below:
  • All plants carry out photosynthesis, but sea sponges do not.  Instead they carry out cellular respiration typical of animals.  
  • Sea sponges do not have cell walls or chloroplast typical of plants, but contain animal cells.
  • However, like a plant, they do attach themselves to rocks, reefs and the ocean floor by rooting themselves to a spot.  This trait is shared by other animals such as mussels, coral and sea anemones.
  • Sea sponges lack a brain and have no true tissues, lacking muscles, nerves, and internal organs. Lacking a brain is not unique in the animal kingdom, and sea sponges share this trait with other creatures such as jellyfish and starfish.
  • Unlike plants, seas sponges have a skeleton. This is made of Calcium Carbonate, Silicon Dioxide or spongin protein.
  • Since it doesn't have much in the way of body functions, such as a digestive, nervous, or even circulatory system, it survives by filtering water through itself and eating the bacteria and microscopic organisms found there for food. It has a specialised cell called the choanocyte which forms an very basic digestive system 

Thursday 17 May 2012


Common Ragwort (Senecio jacobaea) is a biennial plant; a rosette the first year and flowering  when mature during the second year. Ragwort stands between 30 -90 cms and is recognised by it bright yellow, daisy like flowers.  Its downy seeds are spread on the wind and a single plant can produce over 100,000 seeds.

It is a specified weed under the Weeds Act 1959. It contains toxins, which can have debilitating or fatal consequences if eaten by horses and other grazing animals.

Ragwort may need to be controlled when its presence and the likelihood of it spreading to neighbouring land poses a risk to horses and other grazing animals or land used for the production of forage.

Ragwort is difficult to eradicate as its seeds can lay dormant in the grounds for over twenty years.

You can pull up any plants. Ragwort is a toxic plant and suitable precautions must be taken when handling both live and dead plants. Hands must be protected by wearing sturdy waterproof gloves.  Arms and legs should also be covered.  A face mask should be used to prevent the inhalation of ragwort pollen or other airborne particles.   If ragwort comes in contact with the bare skin, the area should be thoroughly washed in warm soapy water and rinsed and dried.

Alternatively, you can control ragwort by application of chemical such as Glyphosate.  This is effective if applied to the plant during its rosette stage during its first year. This method avoids the tricky disposal of the plant.

Ragwort is able to set seed, even after being pulled, dug or cut and therefore there is a high risk of seed dispersal to neighbouring land during transportation. To avoid seed dispersal ragwort should only be transported in sealed bags or enclosed containers.  Where plants are bulky they can be cut up to assist packing.  To avoid unnecessary seed dispersal, seed heads should be cut off first and packed.

The safe and effective disposal of ragwort is an important part of ragwort control. Disposing of ragwort responsibly reduces the risk of further spread by seed dispersal and regrowth from root sections.

The options for disposal will depend on the amount of ragwort to be disposed of, the type of site and local resources available. Wherever practicable, ragwort should be disposed of on site. This will reduce the inadvertent spreading of the seeds during transport.

Options for disposal include:

Rotting down 
Small quantities where ragwort can be safely rotted down on site in a rigid plastic compost bin or similar. 

Controlled burning/incineration
DEFRA exemption to Waste Management Licence if small quantities of ragwort (less than 10 tonnes per day) is burnt on site by land owner. 

For disposing of ragwort on or off site.  To be composted to British Standard PAS 100:2005.

Biomass facility or incinerator
Where therr is an onsite biomass facility or incinerator

Waste management company
For large scale disposal where on site disposal is not possible   

For related articles click onto:


Deadly nightshade (Atropa  Belladonna)

Atropa belladonna is a branching herbaceous perennial belonging to the family Solanaceae, grouped together with plants such as potato, tomato and tobacco. Growing from a fleshy rootstock, it can reach a height of 1.5 metres tall.  It has long ovate leaves and purple bell-shaped flowers which are faintly scented. The berries are green, ripening to a shiny black, and approximately 1 cm in diameter. 

It's name, Atropa, derives from Atropos; one of the three Fates who in Greek mythology held the shears which could cut the thread of life. Thus, a plant called ‘Atropa’ can end life.

Deadly nightshade is one of the most toxic plants found in the Western hemisphere. All parts of the plant contain tropane alkaloids. The active agents are atropine, hyoscine (scopolamine), and hyoscyamine, which have anticholinergic properties.

The symptoms of poisoning include dilated pupils, sensitivity to light, blurred vision, tachycardia, loss of balance, staggering, headache, rash, flushing, dry mouth and throat, slurred speech, urinary retention, constipation, confusion, hallucinations, delirium, and convulsions.

The root of the plant is generally the most toxic part, though this can vary from one specimen to another. Ingestion of a single leaf of the plant can be fatal to an adult. Casual contact with the leaves can cause skin pustules.

The berries pose the greatest danger to children because they look attractive and have a somewhat sweet taste. The consumption of two to five berries by children and ten to twenty berries by adults can be lethal. In 2009 a case of A. belladonna being mistaken for blueberries, with six berries ingested by an adult woman, was documented to result in severe anticholinergic syndrome.

A. belladonna is also toxic to many domestic animals, causing narcosis and paralysis. However, cattle and rabbits eat the plant seemingly without suffering harmful effects In humans its anticholinergic properties will cause the disruption of cognitive capacities like memory and learning.

Its name, belladonna, comes from its use by Venetian women who ate the berries in order to make themselves 'beautiful ladies' by causing their pupils to dilate.

For related articles click onto:

Tuesday 15 May 2012


Poisonous plants are potentially hazardous to all living organisms, which includes not only humans but also pets, livestock and other animals. 

Atropa Belladonna (Deadly Nightshade)
Lots of plants are poisonous and can be too dangerous to eat. Daffodil bulbs, holly berries, irises, poinsettias and even apple seeds are dangerous to people. 

Plants have developed these special defences over thousands of years. Unlike people and animals that can walk and crawl around, plants are pretty much stuck in the same place for their entire lives. Because they can’t really move too much, some plants have figured out some useful ways to protect themselves from animals that might want to eat them. Some plants like rose bushes grow sharp thorns, while others have made themselves poisonous!

Almost any plant can be poisonous. The humble Marigold, Calendula officinalis, is said to act as an insect repellent so eating huge amounts of it might be expected to be harmful. Indeed, though used extensively both as an herbal medicine and as a tasty addition to a salad, its consumption when pregnant is not recommended.

Senecio jacobaea  (Ragwort)
Human beings are not the only ones who can be affected by poisonous plants. Animals are also at risk for being poisoned by certain plants and flowers. Animals that are particularly vulnerable are domestic pets and livestock like cows, pigs and horses. It is advised that farmers and others who own land with livestock grazing on it evaluate their property to discover if there are any poisonous plants and flowers on it.

Poisonous plants can be found everywhere all over the world. People most often come into contact with and interact with poisonous plant when out in nature, either hiking or just taking a walk on a weekend afternoon. Children especially are vulnerable to coming into contact with poisonous plants because of how inquisitive they are by nature and how curious they are to touch almost everything.

While most flowers and plants may look harmless, there are a variety of poisonous plants that can be toxic, or even deadly, to humans and animals. Accidental plant poisoning is very unusual and only very rarely do people suffer serious harm. Death from accidental ingestion of a poisonous plant, in its natural state, is exceptionally unusual. It is in the best interest of people to be able to identify at least some of them to avoid coming into contact with them.

Amanita muscaria (Fly agaric)
List of notable poisonous plants
For related articles click onto:
Bella donna
How to propagate using division
Poisonous plants

Saturday 12 May 2012


Click here for the 'Seeds of Eaden' seed shop 

Often the terms Yam or Sweet Potato are used interchangeably. However, although they are both starchy tubers used for cooking, they are really two different types of vegetables.


Yam is the common name for the tuber of the herbaceous tropical vine Dioscorea batatas. 

Originating from Africa/Asia, yams are closely related to lilies and grasses. They differ from sweet pototos as they are monocots, having a single embronic leaf. 

Yams thrive in tropical climates such as South America, Africa and the Caribbean. Over 95% of yams are cultivated in Africa.

There are over 600 varieties of yam.  They vary from the size of a small potato to over seven feet in length, and can weigh up to 70 kilogrammes / 154 lb.  The tubers are long and cylindrical. They have a rough textured brown/black skin and a off white, purple or red flesh depending on the variety. Starchier and drier than sweet potatoes, yams taste sweeter as they contain more natural sugar.

Sweet potatoes

Often sweet potatoes have been referred to as yams, especially in parts of America and Canada.

Sweet potatoes are storage roots from the plant Ipomoea batatas, members of the morning glory family Convolvulacea. They originate from tropical America (Peru, Ecuador). They are dicots, having two embryonic seed leaves.

They have skin colour ranging from white to yellow, red , purple or brown. The elongated tubers are short and blocky, with ends that taper to a point. 

Sweet potato varieties are often classified as 
soft or hard. Hard varieties have a thinner skin that is light yellow and a dry, crumbly texture that is similar to a baking potato. Softer varieties become soft and moist when cooked and have a thicker, dark orange or red skin with a vivid orange flesh and a moist texture.

For related articles click onto:

Thursday 10 May 2012


Click here for the 'Seeds of Eaden' seed shop

The Greenhouse Effect

Greenhouse gases regulate our climate by trapping heat from the sun and holding it in a kind of warm air blanket that surrounds the earth. The natural greenhouse effect keeps the Earth's climate warm and habitable.  Without it out planet would be way too cold to sustain our ecosystem.  

About 80-90% of the Earth's natural greenhouse effect is due to water vapour, a strong greenhouse gas. The remainder is due to carbon dioxide, methane, and a few other minor gases.

There is also the "man-made" greenhouse effect, which is the enhancement of Earth's natural greenhouse effect by the addition of greenhouse gases from the burning of fossil fuels (mainly petroleum, coal, and natural gas). 

Human activities distort and accelerate the natural process by creating more greenhouse gases in the atmosphere. An increase in the concentration of greenhouse gases leads to an increase in the magnitude of the greenhouse effect. This is referred to as the enhanced greenhouse effect.

It is the carbon dioxide concentration that is increasing, due to the burning of fossil fuels 
(as well as from some rain forest burning). This is the man-made  portion of the greenhouse
effect, and it is believed by many scientists to be responsible for the global warming of the last 
150 years. 

Global Warming


Greenhouse gases regulate our climate by trapping heat from the sun and holding it in a kind of 
warm air blanket that surrounds the earth.  Without it out planet would be colder by 54F, way too 
cold to sustain our ecosystem.

Greenhouse gases trap some of the infrared radiation that escapes from the Earth, 
making the Earth warmer that it would otherwise be. Greenhouse gases act as a "blanket" for 
infrared radiation; it keeps the lower layers of the atmosphere warmer and the 
upper layers colder than if the greenhouse gases were not there. 

The "natural" greenhouse effect keeps the Earth's climate warm and habitable. About 80-90% of 
the Earth's natural greenhouse effect is due to water vapor, a strong greenhouse gas. The 
remainder is due to carbon dioxide, methane, and a few other minor gases. 

There is also the "man-made" greenhouse effect, which is the enhancement of Earth's natural greenhouse effect by the addition of greenhouse gases from the burning of fossil fuels (mainly 
petroleum, coal, and natural gas). 

An increase in the concentration of greenhouse gases leads to an increase in the magnitude of 
the greenhouse effect. This is referred to as the enhanced greenhouse effect.  The problem with 
the greenhouse effect is when human activities distort and accelerate the natural process by 
creating more greenhouse gases in the atmosphere.  

It is the carbon dioxide concentration that is increasing, due to the burning of fossil fuels 
(as well as from some rainforest burning). This is the man-made  portion of the greenhouse
effect, and it is believed by many scientists to be responsible for the global warming of the last 
150 years. 

Also, the concentration of methane, although small, has also increased in recent decades. The
reasons for this increase, though, are uncertain.

Based on the following article,  
Photos care of, and

For related articles click onto:
Acid rain and its effect on wildlife
Caring for the coral reefs
Causes of acid rain
Coral reefs and the greenhouse effect
Conserving fossil fuels
Energy saving light bulbs
Fossil Fuels
Fossil fuels: Alternative sources of energy
What is acid rain?
What is the difference between an asteroid and a comet?
What is global warming?
What is global warming?
What is the greenhouse effect
What is the difference between a fog and a mist??
What is the Gulf Stream?
What is the difference between energy efficient light bulbs and traditional light bulbs?