Fun Fact: Farmers in England used to threaten poorly producing apple trees with violence to encourage them to bear fruit.
If the threat didn’t work, the tree would be shot the following year. Completely coincidently, this total overreaction often worked by relieving a tight, inhibiting bark.
If violence isn’t a-peel-ing to you (against your core values?), you could try dressing your tree in ladies’ clothes instead. In Germany, orchardists saw a tree that wasn’t producing as male and dressed it in petticoats to encourage a change to “fruitful femininity”. Alternatively, a poorly producing “male” tree could be tied to a fruitful “female” tree with straw and Christmas sausages, they would be proclaimed to be married and urged to bear fruit.
Fun Fact: Lichens may have been the first farmers on the planet.
The simple lichen Winfrenatia from the Devonian Period (407 million years ago) was made mostly of undifferentiated fungal hyphae arranged as a mat, anchoring it to its growing surface. Scattered throughout this mat, cyanobacterial cells (photobionts) were held in place in tiny pits, like “pigs in a pen”. The fungi fed on the energy the photobionts generated when they were exposed to sunlight. A cross section of Winfrenatia is below (drawing by Falconaumanni from Wikimedia Commons). Just look at those little piggies!
On the spectrum of mutually beneficial interactions, it is difficult to separate the fungi/photobiont relationship from any other form of domestication. Some fungi even resort to rustling – only forming lichens by killing other lichen-forming fungi and stealing their photobionts before settling down as a lichen themselves.
If you’re interested in more reading, see Otherlands, by Thomas Halliday. A great read about natural history… 550,000,000 years of it… I bet he’s a fungi at parties…If I ever meet him, I’ll give him a hyph-ive.
Fun Fact: If a pollinator is spending too much time drinking nectar, a flower will smack it with a stamen to encourage it to move along.
In some flowers, pollen-containing mobile stamens snap forward when a visiting insect’s tongue touches the nectar-producing parts. Linnaeus first observed these “mobile stamens” in 1775 but no one has been able to explain their purpose…until now.
A team of researchers from China recently found that plants use rapidly moving stamens to enhance the turnover of bees and flies on their flowers, thereby reducing their nectar costs per successfully transported pollen grain. In their study on barberry flowers, insects visiting flowers with immobilised stamens stayed 3.6 times longer and removed more nectar than those visiting flowers with mobile stamens. They also found that insect visitors deposited pollen from flowers with mobile stamens on about three times more flowers, and on flowers further away, increasing the likelihood of reproductive success for the plant.
Sounds like a pushy waiter at a restaurant… truly a-pollen’ behaviour. They should bee ashamed.
Fun Fact: There is a genus of orchid in Western Australia that spends its entire lifecycle underground…including flowering.
Unsurprisingly, it’s really hard to find. The first species, Rhizanthella gardneri, wasn’t discovered until 1928 when a farmer ploughed his field and found the strange, fleshy, leafless plants (see below). As of 2020, there have been five species described, but they are considered to be critically endangered and their locations are kept secret.
Since they spend their whole lives underground and away from the sun, species of the genus rhizanthella (from the Greek: rhiza [root], and Anthos [flower]…root flower) have given up their ability to photosynthesise and instead rely on a complicated, multi-species relationships to survive. Rhizanthella species are mycotrophic (plants that get all or part of their carbon, water, or nutrients from fungi), but the fungus that it relies on also has a mycorrhizal relationship (fungi that have symbiotic relationships with plants) with the broom bush shrub, which it relies on for photosynthesized carbohydrates. The relationship is so critical that the seeds of the orchid will only germinate when infected by a fungus that is actively “mycorrhizing” with the broom bush.
When it flowers, the blooms typically stay several centimetres below the soil surface, with the very tips of the flowers poking through the surface only occasionally. We don’t know who pollinates it, how many there are, why they have bothered to keep their chloroplasts…
We’re completely in the dark on this one…researchers are practically buried in work… ok, no m-orchid-ding around…
Fun Fact: Kew Gardens lost track of a giant waterlily with three-metre-wide leaves for 177 years.
Until now, Victoria boliviana was mis-identified as one of the two known varieties V. amazonica and V. cruziana, but researchers at Kew Gardens noticed differences in the patterns of the spines that are used to clear space for their unfurling leaves. V. boliviana is now recognized as the largest species of giant waterlily. Its leaves expand by 25 cm a day and can hold the weight of an adult (more than 170 lbs). Turns out a mis-labelled specimen has been sitting at Kew since 1845!
In addition to their famously large leaves, giant waterlilies also have a very cool two-night reproductive cycle. On night one, the temperature of the white female flower rises 10 degrees C, triggering it to open and attracting pollinator beetles to its sweet, pineapple scent. At dawn, the flower cools and closes, trapping the beetles inside. They get to spend the day cool and shaded and sipping away at nectar while the flower changes from white to pink and male to female. On the second night, the newly male flower opens, brushing the beetles with pollen as they leave and head to another white female flower.
Fun Fact: Your house plants remember when you left for holiday without watering them, and they are not happy about it.
Researchers at the University of Western Australia have shown that the sensitive plant (Mimosa pudica) can not only learn from experience but can also remember those lessons weeks later. M. pudica, is a perennial plant in the pea family (Fabaceae) and is native to the Caribbean and South and Central America. It is known for its rapid movement where it folds up its leaves as a defence mechanism when touched or otherwise suddenly stressed (nyctinastic movement). You can often find sad little M. pudica plants at nurseries that have been harassed by passers-by. Please rescue them.
The researchers from Australia found that the M. pudica they were studying for an unrelated research question quickly stopped curling their leaves in response to being ‘alarmed’ but not harmed. The authors suggest that this shows that they had learned that folding your leaves in this scenario was a waste of valuable energy. Furthermore, they found that their subjects remembered this lesson and didn’t close their leaves when exposed to the same “scary” situation a month later.
If you are interested in further reading on the M. pudica study, see their paper: Gagliano M et al. 2014. Experience teaches plants to learn faster and forget slower in environments where it matters. Oecologia, published online January 05, 2014; doi: 10.1007/s00442-013-2873-7
Fun Fact: Sphagnum moss was so important for wound dressing during World War I that someone wrote a poem about it.
The Flanders poppy (Papaver rhoeas) thrived in the battlefields of the Western Front after exploding shells brought its dormant buried seeds to the surface. It has been the symbol of remembrance for war veterans in several countries ever since, but maybe we should also be wearing sphagnum pins in November.
Sphagnum moss was used for centuries to bind wounds suffered in battle. Warriors wounded in the battle of Clontarf (1014) stuffed their wounds with moss, and there are also records of its use from the Highlanders in the battle of Flodden (1513), and both the Crimean (1853 to 1856) and Franco-Prussian (1870-1871) wars. During the first world war, the collection and production of sphagnum moss dressings began on an industrial scale. Initially, collections were made by Scottish women and children (often boy scouts and girl guides), working for long hours in cold, wet bogs. By the end of the war, collections were being made throughout Ireland, England, Canada, and the US; Britain alone was producing 1,000,000 sphagnum dressings per month.
The process of collecting, drying, and preparing dressings for WWI soldiers was pioneered by Charles Walker Cathcart, a surgeon in Edinburgh. They were very effective. Dried sphagnum can absorb up to twenty-two times its own weight of liquid, including blood, pus, and lymph, before it starts to drip. It was far superior to inert cotton wool dressings, which were both expensive and increasingly difficult to source – cotton was used to manufacture gun cotton or nitrocellulose explosives. The preferred species for wound dressings were S. papillosum and S. palustre. Because of their ability to absorb and hold liquids, sphagnum could also be used as surgical swabs and cushions that kept beds dry while wounds were being irrigated. Under field conditions, I can imagine that a dry bed was a good bed.
In addition to its absorptive power, Sphagnum also has antiseptic properties thanks to the pectic polysaccharides (sphagnan) contained in their cell walls. Recent research from Scandinavia (where sphagnum is used to pack fresh fish), suggests the antiseptic properties are driven by the ability of sphagnum cell walls to lower the pH of their environment sufficiently to inhibit the growth of bacterial colonies.
The following poem was written by Mrs AM Smith (1917), a member of the Edinburgh Ware Dressings Supply Organisation:
Fun Fact: Your distressed house plants are living out a silent horror movie.
A team of researchers at Tel Aviv University has recorded “high frequency distress sounds” emitted from tobacco and tomato plants. After stressing the plants by cutting their stems and depriving them of water (rude), the researchers recorded their responses with a microphone. In both cases they found the plants emitted ultrasonic sounds between 20 and 100 kilohertz, which they suggested conveyed their distress to other plants and organisms in the immediate vicinity.
The plants seemed to respond with different intensities of sound to different sources of stress. The team observed that tobacco plants “screamed” louder when they were deprived of water than when they had their stems cut. They believe that listening for sounds emitted by plants could help with precision agriculture and identify problems with crops.
It’s easy to understand the ecological damage animals suffer as a result of noise pollution, but it has been less clear how it affects plants…until now. The indirect effects are obvious. Flowering species depend on pollinators and fruit-bearing species need animals to disperse their seeds. If the noise is a problem for their animal partners, botanical counterparts will also suffer. A recent study by Dr. Ghotbi-Ravandi, a botanist at Shahid Beheshti University in Tehran, has shown that plants are also directly affected by noise.
A number of experiments have shown that plants can sense ultrasound waves as they are struck by them, but this isn’t quite the same as urban noise pollution. In their lab, Dr. Ghotbi-Ravandi and his team grew two species that are commonly found in urban environments: French marigolds (Tagetes patula) and scarlet sage (Salvia splendens). Once mature, the plants were divided into two groups. One was exposed to 73 decibels of traffic noise for 16 hours a day, and the other was left to grow in silence. After just 15 days all of the plants in the noisy group were suffering. Two chemical compounds (hydrogen peroxide and malondialdehyde) that are indicators of stress in plants were found at much higher levels (2 to 3 times) in the group exposed to the traffic noise. Two stress hormones (jasmonic acid and abscisic acid) which are normally produced to fend off insect attacks and deal with harsh environmental conditions, were also elevated, and a range of hormones normally associated with healthy growth and development were present at significantly reduced levels in the plants exposed to the noise.
The vibrations generated by traffic noise bothered the plants in the study enough to trigger stress responses that are not much different than if they had been exposed to drought, high salinity, or heavy metals in their soil. . I guess we’ll have to call it “road sage” now…
If you’re interested in more reading, see their paper: Z.H. Kafash, Khoramnejadian S., Ghotbi-Ravandi A.A., Dehghan S.F. 2022. Traffic noise induces oxidative stress and phytohormone imbalance in two urban plant species. Basic and Applied Ecology. Volume 60. Pages 1-12.
Fun Fact:Roman emperor Heliogabalus (203 – 222 AD)once dropped so many flower petals on his dinner guests that they drowned.
While we slowly get back to socialising, one might feel a twinge of anxiety at the idea of hosting a get-together. But don’t worry, it will never go as poorly as this one did:
It was such a disastrous event that someone commissioned a painting about it 1,600 years later. The Roses of Heliogabalus was painted in 1888 by Anglo-Dutch artist Sir Lawrence Alma-Tadema and depicted the young emperor hosting a banquet. The original account of the (likely exaggerated) story from Historia Augusta described a false ceiling that fell away to release a fluttering and then a torrent of violet petals. Alma-Tadema, apparently a student of floriography, decided that roses would be more appropriate. Violets represent faithfulness and modesty according to the Victorian ‘language’… none of that here.
Since roses were out of season at the time and every petal needed to be perfect, fresh roses were shipped in weekly from the south of France during the four months it took to complete the painting. A simpler solution might have been to wait until spring, but who am I to judge. Artists can be a prickly bunch.
