Fact Archive

Like the Himalayan Balsam, the squirting cucumber also uses explosive seed dispersal. As the seed pod matures, pressure builds, until finally, the seed pod is launched similar to a missile, landing up to 8m away from the parent plant.

Explosive seed dispersal is a strategy involving rapid movements to launch seeds into the air and disperse them. The Himalayan Balsam uses this strategy- if you find a seed pod that's almost ripe, just a tiny touch will be enough to make the pod explode and disperse the seed (although unfortunately it's a highly invasive species, so don't try this too much!)

The leaves of Microsorum punctatum, more commonly known as the Wart Fern, are covered in raised, wart-like structures known as sori. These sori are spore-producing structures characteristic of ferns. In the wart fern, the sori are actually located on the underside of the leaf, but are sunken so deep that they form wart-like protrusions on the upper leaf surface.

The roots of most plants are relatively shallow, often relying on a relatively consistent pattern of rainfall to support growth. However, phreatophytes have a much deeper root system, commonly up to 10 m deep, allowing them to reach down to the permanent groundwater table. Lucerne, Welwitschia, and willow are all phreatophytes.

Normally, the leaves of stinging nettles are covered in stinging hairs (trichomes) that when broken (e.g. by contact human skin) release chemicals that cause stinging/ itching. This works because the trichomes are covered in a very thin layer of silica (effectively glass) which snaps upon contact to release the irritant chemicals inside. In the lab, nettles grown without silicon lose the ability to sting

Welwitschia mirabilis is a unique desert plant that produces only 2 leaves in its entire life (although they split into segments over time, making it appear like the plant has more leaves), each lasting for up to 2000 years. Plants can survive for 100s of years in the desert by absorbing water from sea fog and deep ground water.

Many flowers, particularly those pollinated by bees, have special UV markings that direct bees (or other pollinators) to the centre of the flower. Unlike humans, bees can see in UV and these markings act similarly to the markings in an airport landing strip, guiding the bee into the flower for it's nectar reward, and ensuring that the flower is properly pollinated.

A tiny fern species holds the current record for the largest genome. The genome of Tmesipteris oblanceolate is 160 billion base pairs (Gbp), compared to only 3.1 Gbp for the human genome. What does all this extra DNA do? Unlike animals, many plants are able to undergo whole genome duplication events which increase the size of their genome without problems, possibly as an adaptation to environmental stress

Mangroves grow in tropic and subtropic coastal regions. These flooded environments are anaerobic so mangroves produce aerial roots that grow above the water level, which use tiny pores, lenticels, to absorb oxygen from the air. Similar to stomata, lenticels can close if the root becomes submerged, preventing saline water from entering the plant.

In many species, when plants are attacked by herbivores, they release special chemicals known as Herbivore-induced plant volatiles (HIPVs) which can be used to attract natural predators or parasitoids of would-be herbivores. Therefore, plants can recruit their enemy's (herbivores) enemy (parasitoids) as a way of protecting themselves

Rubisco is an essential protein used in photosynthesis to fix atmospheric CO₂ into sugars, and it's often claimed to be the most abundant protein on earth. It has been estimated that there are 5 kg of Rubisco per person on Earth. However, Rubisco is also an infamously slow and inefficient protein, prone to fixing O₂ instead of CO₂ hence why some plants have evolved special mechanisms to improve carbon fixation by Rubisco.

Many people are familiar with the Venus Flytrap, which is capable of rapid movement to trap insects which it then uses as a source of nitrogen. This movement seems to be the result of the plant's cell walls rapidly softening upon insect detection, which releases stored elastic energy that allows the trap to close within 0.2 seconds

Despite the description of plants as sessile organisms, they are able to move to some extent. Circumnutation is a term used to describe the circular movements made by plant shoots. Many climbing plants use this movement to search for something (another plant, a garden stake) to twine around and climb up.

There's a lot of debate about the use of Genetically Modified (GM) crops. In research labs, GM is often done by introducing a bacteria, Agrobacterium tumefaciens, which transfers DNA into the plant. However, this bacteria also occurs naturally, and sweet potato has been found to naturally contain DNA transferred by this bacteria, making sweet potato a naturally GM plant

Plants use the energy of the sun to make food through the process of photosynthesis, right? So surely photosynthesis can only happen when the sun is out? Actually, many desert plants use a special form of photosynthesis known as Crassulacean acid metabolism (CAM). Such plants still collect energy from the sun during the day to fuel photosynthesis. However, gas exchange, i.e. the entry of CO2, needed for photosynthesis, only happens at night, allowing such plants to be much more water efficient.

Tree-ferns are a type of fern that have a tree-like growth form with a trunk. However, the trunk is not made of wood but is formed from old fronts (fern leaves) and roots. Thus, tree-ferns can be considered as having the growth form of a tree, but are not trees in the strictest sense in that they don't produce wood.

Although we're taught in school that the trademark of a plant is their ability to photosynthesize, that's not always the case, with several species having lost their ability to photosynthesize. Instead, such plants often parasitize other plants, stealing their nutrients, as as is the case for the important crop weed, Striga. In other cases the plant may parasitize fungi that live in the soil, as is the case for many orchid species.

In botany, a flower is a single reproductive unit. However, many of the things we call "flowers" are actually composite inflorescences: structures formed of groups of flowers. Thus, while at up to 3m high, the titan arum holds the title for the world's largest known inflorescence, it is not composed of a single flower. Instead, the title of the world's largest flower, at up to 1 m wide, belongs to the corpse flower, Rafflesia arnoldi, so-called due to the distinct smell of dead flesh it produces